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Observations of anthropogenic global warming

New research – climate sensitivity, forcings, and feedbacks (September 22, 2016)

Posted by Ari Jokimäki on September 22, 2016

Some of the latest papers on climate sensitivity, forcings, and feedbacks are shown below. First a few highlighted papers with abstracts and then a list of some other papers. If this subject interests you, be sure to check also the other papers – they are by no means less interesting than the highlighted ones.

Highlights

The Effects of Ocean Heat Uptake on Transient Climate Sensitivity (Rose & Rayborn, 2016) http://rd.springer.com/article/10.1007%2Fs40641-016-0048-4

Abstract: Transient climate sensitivity tends to increase on multiple timescales in climate models subject to an abrupt CO2 increase. The interdependence of radiative and ocean heat uptake processes governing this increase are reviewed. Heat uptake tends to be spatially localized to the subpolar oceans, and this pattern emerges rapidly from an initially uniform distribution. Global climatic impact of heat uptake is studied through the lens of the efficacy concept and a linear systems perspective in which responses to individual climate forcing agents are additive. Heat uptake can be treated as a slowly varying forcing on the atmosphere and surface, whose efficacy is strongly determined by its geographical pattern. An illustrative linear model driven by simple prescribed uptake patterns demonstrates the emergence of increasing climate sensitivity as a consequence of the slow decay of high-efficacy subpolar heat uptake. Evidence is reviewed for the key role of shortwave cloud feedbacks in setting the high efficacy of ocean heat uptake and thus in increasing climate sensitivity. A causal physical mechanism is proposed, linking subpolar heat uptake to a global-scale increase in lower-tropospheric stability. It is shown that the rate of increase in estimated inversion strength systematically slows as heat uptake decays. Variations in heat uptake should therefore manifest themselves as differences in low cloud feedbacks.

Understanding Climate Feedbacks and Sensitivity Using Observations of Earth’s Energy Budget (Loeb et al. 2016) http://rd.springer.com/article/10.1007%2Fs40641-016-0047-5

Abstract: While climate models and observations generally agree that climate feedbacks collectively amplify the surface temperature response to radiative forcing, the strength of the feedback estimates varies greatly, resulting in appreciable uncertainty in equilibrium climate sensitivity. Because climate feedbacks respond differently to different spatial variations in temperature, short-term observational records have thus far only provided a weak constraint for climate feedbacks operating under global warming. Further complicating matters is the likelihood of considerable time variation in the effective global climate feedback parameter under transient warming. There is a need to continue to revisit the underlying assumptions used in the traditional forcing-feedback framework, with an emphasis on how climate models and observations can best be utilized to reduce the uncertainties. Model simulations can also guide observational requirements and provide insight on how the observational record can most effectively be analyzed in order to make progress in this critical area of climate research.

Insights from a Refined Decomposition of Cloud Feedbacks (Zelinka et al. 2016) http://onlinelibrary.wiley.com/doi/10.1002/2016GL069917/abstract

Abstract: Decomposing cloud feedback into components due to changes in several gross cloud properties provides valuable insights into its physical causes. Here we present a refined decomposition that separately considers changes in free tropospheric and low cloud properties, better connecting feedbacks to individual governing processes and avoiding ambiguities present in a commonly used decomposition. It reveals that three net cloud feedback components are robustly nonzero: positive feedbacks from increasing free tropospheric cloud altitude and decreasing low cloud cover and a negative feedback from increasing low cloud optical depth. Low cloud amount feedback is the dominant contributor to spread in net cloud feedback but its anticorrelation with other components damps overall spread. The ensemble mean free tropospheric cloud altitude feedback is roughly 60% as large as the standard cloud altitude feedback because it avoids aliasing in low cloud reductions. Implications for the “null hypothesis” climate sensitivity from well-understood and robustly simulated feedbacks are discussed.

Rapid systematic assessment of the detection and attribution of regional anthropogenic climate change (Stone & Hansen, 2016) http://link.springer.com/article/10.1007%2Fs00382-015-2909-2

Abstract: Despite being a well-established research field, the detection and attribution of observed climate change to anthropogenic forcing is not yet provided as a climate service. One reason for this is the lack of a methodology for performing tailored detection and attribution assessments on a rapid time scale. Here we develop such an approach, based on the translation of quantitative analysis into the “confidence” language employed in recent Assessment Reports of the Intergovernmental Panel on Climate Change. While its systematic nature necessarily ignores some nuances examined in detailed expert assessments, the approach nevertheless goes beyond most detection and attribution studies in considering contributors to building confidence such as errors in observational data products arising from sparse monitoring networks. When compared against recent expert assessments, the results of this approach closely match those of the existing assessments. Where there are small discrepancies, these variously reflect ambiguities in the details of what is being assessed, reveal nuances or limitations of the expert assessments, or indicate limitations of the accuracy of the sort of systematic approach employed here. Deployment of the method on 116 regional assessments of recent temperature and precipitation changes indicates that existing rules of thumb concerning the detectability of climate change ignore the full range of sources of uncertainty, most particularly the importance of adequate observational monitoring.

One Year of Downwelling Spectral Radiance Measurements from 100 to 1400 cm−1 at Dome-Concordia: Results in Clear Conditions (Rizzi et al. 2016) http://onlinelibrary.wiley.com/doi/10.1002/2016JD025341/abstract

Abstract: The present work examines downwelling radiance spectra measured at the ground during 2013 by a Far Infrared Fourier Transform Spectrometer at Dome-C, Antarctica. A tropospheric backscatter and depolarization Lidar is also deployed at same site and a radiosonde system is routinely operative. The measurements allow characterization of the water vapor and clouds infrared properties in Antarctica under all sky conditions. In this paper we specifically discuss cloud detection and the analysis in clear sky condition, required for the discussion of the results obtained in cloudy conditions. Firstly, the paper discusses the procedures adopted for the quality control of spectra acquired automatically. Then it describes the classification procedure used to discriminate spectra measured in clear-sky from cloudy conditions. Finally a selection is performed and 66 clear cases, spanning the whole year, are compared to simulations. The computation of layer molecular optical depth is performed with line-by-line techniques and a convolution to simulate the REFIR-PAD measurements; the downwelling radiance for selected clear cases is computed with a state-of-the-art adding-doubling code. The mean difference over all selected cases between simulated and measured radiance is within experimental error for all the selected micro-windows except for the negative residuals found for all micro-windows in the range 200 to 400 cm−1, with largest values around 295.1 cm−1. The paper discusses possible reasons for the discrepancy and identifies the incorrect magnitude of the water vapor total absorption coefficient as the cause of such large negative radiance bias below 400 cm−1.

Other papers

Dependence of global radiative feedbacks on evolving patterns of surface heat fluxes (Rugenstein et al. 2016) http://onlinelibrary.wiley.com/doi/10.1002/2016GL070907/abstract

Understanding the varied influence of mid-latitude jet position on clouds and cloud-radiative effects in observations and global climate models (Grise & Medeiros, 2016) http://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-16-0295.1

Effect of land cover change on snow free surface albedo across the continental United States (Wickham et al. 2016) http://www.sciencedirect.com/science/article/pii/S0921818116302892

Forced response and internal variability of summer climate over western North America (Kamae et al. 2016) http://rd.springer.com/article/10.1007%2Fs00382-016-3350-x

Detection and attribution of climate change at regional scale: case study of Karkheh river basin in the west of Iran (Zohrabi et al. 2016) http://rd.springer.com/article/10.1007%2Fs00704-016-1896-5

Atmospheric lifetimes, infrared absorption spectra, radiative forcings and global warming potentials of NF3 and CF3CF2Cl (CFC-115) (Totterdill et al. 2016) http://www.atmos-chem-phys.net/16/11451/2016/

A long-term study of aerosol–cloud interactions and their radiative effect at the Southern Great Plains using ground-based measurements (Sena et al. 2016) http://www.atmos-chem-phys.net/16/11301/2016/

Detection of dimming/brightening in Italy from homogenized all-sky and clear-sky surface solar radiation records and underlying causes (1959–2013) (Manara et al. 2016) http://www.atmos-chem-phys.net/16/11145/2016/

Effects of 20–100 nm particles on liquid clouds in the clean summertime Arctic (Leaitch et al. 2016) http://www.atmos-chem-phys.net/16/11107/2016/

Assessment of the first indirect radiative effect of ammonium-sulfate-nitrate aerosols in East Asia (Han et al. 2016) http://rd.springer.com/article/10.1007%2Fs00704-016-1913-8

Sensitivity of precipitation extremes to radiative forcing of greenhouse gases and aerosols (Lin et al. 2016) http://onlinelibrary.wiley.com/doi/10.1002/2016GL070869/abstract

Global climate forcing of aerosols embodied in international trade (Lin et al. 2016) http://www.nature.com/ngeo/journal/vaop/ncurrent/full/ngeo2798.html

Reprocessing of HIRS Satellite Measurements from 1980-2015: Development Towards a Consistent Decadal Cloud Record (Menzel et al. 2016) http://journals.ametsoc.org/doi/abs/10.1175/JAMC-D-16-0129.1

Radiative Forcing from Anthropogenic Sulfur and Organic Emissions Reaching the Stratosphere (Yu et al. 2016) http://onlinelibrary.wiley.com/doi/10.1002/2016GL070153/abstract

Near miss: the importance of the natural atmospheric CO2 concentration to human historical evolution (Archer, 2016) http://rd.springer.com/article/10.1007%2Fs10584-016-1725-y

Long-Term Variations of Noctilucent Clouds at ALOMAR (Fiedler et al. 2016) http://www.sciencedirect.com/science/article/pii/S1364682616302024

Estimating Arctic sea-ice shortwave albedo from MODIS data (Qu et al. 2016) http://www.sciencedirect.com/science/article/pii/S0034425716303182

Surface albedo raise in the South American Chaco: Combined effects of deforestation and agricultural changes (Houspanossian et al. 2016) http://www.sciencedirect.com/science/article/pii/S0168192316303707

New Observational Evidence for a Positive Cloud Feedback that Amplifies the Atlantic Multidecadal Oscillation (Bellomo et al. 2016) http://onlinelibrary.wiley.com/doi/10.1002/2016GL069961/abstract

Surface water and heat exchange comparison between alpine meadow and bare land in a permafrost region of the Tibetan Plateau (You et al. 2016) http://www.sciencedirect.com/science/article/pii/S0168192316303598

foF2 vs Solar Indices for the Rome station: looking for the best general relation which is able to describe the anomalous minimum between cycles 23 and 24 (Perna & Pezzopane, 2016) http://www.sciencedirect.com/science/article/pii/S1364682616301894

Comparison of Methods: Attributing the 2014 record European temperatures to human influences (Uhe et al. 2016) http://onlinelibrary.wiley.com/doi/10.1002/2016GL069568/abstract

Relevance of long term time – series of atmospheric parameters at a mountain observatory to models for climate change (Kancírová et al. 2016) http://www.sciencedirect.com/science/article/pii/S1364682616301882

An energy balance perspective on regional CO2-induced temperature changes in CMIP5 models (Räisänen, 2016) http://rd.springer.com/article/10.1007%2Fs00382-016-3277-2

Posted in Climate claims, Climate science | Leave a Comment »

New research – atmospheric composition (September 19, 2016)

Posted by Ari Jokimäki on September 19, 2016

Some of the latest papers on atmospheric composition (mainly on greenhouse gases and aerosols) are shown below. First a few highlighted papers with abstracts and then a list of some other papers. If this subject interests you, be sure to check also the other papers – they are by no means less interesting than the highlighted ones.

Highlights

A global catalogue of large SO2 sources and emissions derived from the Ozone Monitoring Instrument (Fioletov et al. 2016) http://www.atmos-chem-phys.net/16/11497/2016/

Abstract: Sulfur dioxide (SO2) measurements from the Ozone Monitoring Instrument (OMI) satellite sensor processed with the new principal component analysis (PCA) algorithm were used to detect large point emission sources or clusters of sources. The total of 491 continuously emitting point sources releasing from about 30 kt yr−1 to more than 4000 kt yr−1 of SO2 per year have been identified and grouped by country and by primary source origin: volcanoes (76 sources); power plants (297); smelters (53); and sources related to the oil and gas industry (65). The sources were identified using different methods, including through OMI measurements themselves applied to a new emission detection algorithm, and their evolution during the 2005–2014 period was traced by estimating annual emissions from each source. For volcanic sources, the study focused on continuous degassing, and emissions from explosive eruptions were excluded. Emissions from degassing volcanic sources were measured, many for the first time, and collectively they account for about 30 % of total SO2 emissions estimated from OMI measurements, but that fraction has increased in recent years given that cumulative global emissions from power plants and smelters are declining while emissions from oil and gas industry remained nearly constant. Anthropogenic emissions from the USA declined by 80 % over the 2005–2014 period as did emissions from western and central Europe, whereas emissions from India nearly doubled, and emissions from other large SO2-emitting regions (South Africa, Russia, Mexico, and the Middle East) remained fairly constant. In total, OMI-based estimates account for about a half of total reported anthropogenic SO2 emissions; the remaining half is likely related to sources emitting less than 30 kt yr−1 and not detected by OMI.

Re-evaluating the 1940s CO2 plateau (Bastos et al. 2016) http://www.biogeosciences.net/13/4877/2016/

Abstract: The high-resolution CO2 record from Law Dome ice core reveals that atmospheric CO2 concentration stalled during the 1940s (so-called CO2 plateau). Since the fossil-fuel emissions did not decrease during the period, this stalling implies the persistence of a strong sink, perhaps sustained for as long as a decade or more. Double-deconvolution analyses have attributed this sink to the ocean, conceivably as a response to the very strong El Niño event in 1940–1942. However, this explanation is questionable, as recent ocean CO2 data indicate that the range of variability in the ocean sink has been rather modest in recent decades, and El Niño events have generally led to higher growth rates of atmospheric CO2 due to the offsetting terrestrial response. Here, we use the most up-to-date information on the different terms of the carbon budget: fossil-fuel emissions, four estimates of land-use change (LUC) emissions, ocean uptake from two different reconstructions, and the terrestrial sink modelled by the TRENDY project to identify the most likely causes of the 1940s plateau. We find that they greatly overestimate atmospheric CO2 growth rate during the plateau period, as well as in the 1960s, in spite of giving a plausible explanation for most of the 20th century carbon budget, especially from 1970 onwards. The mismatch between reconstructions and observations during the CO2 plateau epoch of 1940–1950 ranges between 0.9 and 2.0 Pg C yr−1, depending on the LUC dataset considered. This mismatch may be explained by (i) decadal variability in the ocean carbon sink not accounted for in the reconstructions we used, (ii) a further terrestrial sink currently missing in the estimates by land-surface models, or (iii) LUC processes not included in the current datasets. Ocean carbon models from CMIP5 indicate that natural variability in the ocean carbon sink could explain an additional 0.5 Pg C yr−1 uptake, but it is unlikely to be higher. The impact of the 1940–1942 El Niño on the observed stabilization of atmospheric CO2 cannot be confirmed nor discarded, as TRENDY models do not reproduce the expected concurrent strong decrease in terrestrial uptake. Nevertheless, this would further increase the mismatch between observed and modelled CO2 growth rate during the CO2 plateau epoch. Tests performed using the OSCAR (v2.2) model indicate that changes in land use not correctly accounted for during the period (coinciding with drastic socioeconomic changes during the Second World War) could contribute to the additional sink required. Thus, the previously proposed ocean hypothesis for the 1940s plateau cannot be confirmed by independent data. Further efforts are required to reduce uncertainty in the different terms of the carbon budget during the first half of the 20th century and to better understand the long-term variability of the ocean and terrestrial CO2 sinks.

Trace gases in the atmosphere over Russian cities (Elansky et al. 2016) http://www.sciencedirect.com/science/article/pii/S1352231016306392

Abstract: Multiyear observational data (obtained at the mobile railroad laboratory in the course of the 1995–2010 TROICA experiments) on the composition and state of the atmosphere were used to study the features of both spatial and temporal variations in the contents of trace gases in the surface air layer over Russian cities. The obtained characteristics of urban air noticeably differ from those obtained at stationary stations. The emission fluxes of NOx, CO, and CH4 and their integral emissions from large cities have been estimated on the basis of observational data obtained at the mobile laboratory. The values of these emission fluxes reflect the state of urban infrastructure. The integral urban emissions of CO depend on the city size and vary from 50 Gg yr−1 for Yaroslavl to 130 Gg yr−1 for Yekaterinburg. For most cities, they agree with the EDGAR v4.2 data within the limits of experimental error. The agreement is worse for the emissions of NOx. The EDGAR v4.2 data on the emissions of CH4 seem to be overestimated..

Potential sea salt aerosol sources from frost flowers in the pan-Arctic region (Xu et al. 2016) http://onlinelibrary.wiley.com/doi/10.1002/2015JD024713/abstract

Abstract: In order to better represent observed wintertime aerosol mass and number concentrations in the pan-Arctic (60°N-90°N) region, we implemented an observationally-based parameterization for estimating sea salt production from frost flowers in the Community Earth System Model (CESM, version 1.2.1). In this work, we evaluate the potential influence of this sea salt source on the pan-Arctic climate. Results show that frost flower salt emissions increase the modeled surface sea salt aerosol mass concentration by roughly 200% at Barrow and 100% at Alert and accumulation-mode number concentration by about a factor of 2 at Barrow and more than a factor of 10 at Alert in the winter months when new sea ice and frost flowers are present. The magnitude of sea salt aerosol mass and number concentrations at the surface in Barrow during winter simulated by the model configuration that includes this parameterization agrees better with observations by 48% and 12%, respectively, than the standard CESM simulation without a frost-flower salt particle source. At Alert, the simulation with this parameterization overestimates observed sea salt aerosol mass concentration by 150% during winter in contrast to the underestimation of 63% in the simulation without this frost flower source, while it produces particle number concentration about 14% closer to observation than the standard CESM simulation. However, because the CESM version used here underestimates transported sulfate in winter, the reference accumulation-mode number concentrations at Alert are also underestimated. Adding these frost flower salt particle emissions increases sea salt aerosol optical depth by 10% in the pan-Arctic region and results in a small cooling at the surface. The increase in salt aerosol mass concentrations of a factor of 8 provides nearly two times the cloud condensation nuclei concentration at supersaturation of 0.1%, as well as 10% increases in cloud droplet number and 40% increases in liquid water content near coastal regions adjacent to continents. These cloud changes reduce longwave cloud forcing at the top of the atmosphere by 3% and cause a small surface warming, increasing the downward longwave flux at the surface by 1.8 W m−2 in the pan-Arctic under the present-day climate. This regional average longwave warming due to the presence of clouds attributed to frost flower sea salts is roughly half of previous observed surface longwave fluxes and cloud-forcing estimates reported in Alaska, implying that the longwave enhancement due to frost flower salts may be comparable to those estimated for anthropogenic aerosol emissions. Since the potential frost flower area is parameterized as the maximum possible region on which frost flowers grow for the modeled atmospheric temperature and sea ice conditions and the model underestimates the number of accumulation-mode particles from mid-latitude anthropogenic sources transported in winter, the calculated aerosol indirect effect of frost flower sea salts in this work can be regarded as an upper bound.

Early detection of volcanic hazard by lidar measurement of carbon dioxide (Fiorani et al. 2016) http://rd.springer.com/article/10.1007%2Fs11069-016-2209-0

Abstract: Volcanic gases give information on magmatic processes. In particular, anomalous releases of carbon dioxide precede volcanic eruptions. Up to now, this gas has been measured in volcanic plumes with conventional measurements that imply the severe risks of local sampling and can last many hours. For these reasons and for the great advantages of laser sensing, the thorough development of volcanic lidars has been undertaken at ENEA (Italian National Agency for New Technologies, Energy and Sustainable Economic Development). In fact, lidar profiling allows one to scan remotely volcanic plumes in a fast and continuous way, and with high spatial and temporal resolution. A differential absorption lidar instrument will be presented in this paper: BILLI (BrIdge voLcanic LIdar). It is based on injection-seeded Nd:YAG laser, double-grating dye laser, difference frequency mixing and optical parametric amplifier. BILLI is funded by the ERC (European Research Council) project BRIDGE (BRIDging the gap between Gas Emissions and geophysical observations at active volcanos). It scanned the gas emitted by Pozzuoli Solfatara (Naples, Italy) and Stromboli Volcano (Sicily, Italy) during field campaigns carried out from October 13 to 17, 2014, and from June 24 to 29, 2015, respectively. Carbon dioxide concentration maps were retrieved remotely in few minutes in the crater areas. To our knowledge, it is the first time that carbon dioxide in a volcanic plume is retrieved by lidar. This result represents the first direct measurement of this kind ever performed on active volcanos and shows the high potential of laser remote sensing in early detection of volcanic hazard.

Other papers

Validation and update of OMI Total Column Water Vapor product (Wang et al. 2016) http://www.atmos-chem-phys.net/16/11379/2016/

Long-term visibility variation in Athens (1931–2013): a proxy for local and regional atmospheric aerosol loads (Founda et al. 2016) http://www.atmos-chem-phys.net/16/11219/2016/

Particulate air pollution from wildfires in the Western US under climate change (Liu et al. 2016) http://rd.springer.com/article/10.1007%2Fs10584-016-1762-6

Climate-driven ground-level ozone extreme in the fall over the Southeast United States (Zhang et al. 2016) http://www.pnas.org/content/113/36/10025.short

Radon as a tracer of atmospheric influences on traffic-related air pollution in a small inland city (Williams et al. 2016) http://www.tellusb.net/index.php/tellusb/article/view/30967

Bioaerosols in the Earth system: Climate, health, and ecosystem interactions (Fröhlich-Nowoisky et al. 2016) http://www.sciencedirect.com/science/article/pii/S0169809516301995

The importance of non-fossil sources in carbonaceous aerosols in a megacity of central China during the 2013 winter haze episode: A source apportionment constrained by radiocarbon and organic tracers (Liu et al. 2016) http://www.sciencedirect.com/science/article/pii/S1352231016306677

Estimating Minimum Detection Times for Satellite Remote Sensing of Trends in Mean and Extreme Precipitable Water Vapor (Roman et al. 2016) http://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-16-0303.1

A comprehensive estimate for loss of atmospheric carbon tetrachloride (CCl4) to the ocean (Butler et al. 2016) http://www.atmos-chem-phys.net/16/10899/2016/

Significant increase of summertime ozone at Mount Tai in Central Eastern China (Sun et al. 2016) http://www.atmos-chem-phys.net/16/10637/2016/

Snow Covered Soils Produce N2O that is Lost from Forested Catchments (Enanga et al. 2016) http://onlinelibrary.wiley.com/doi/10.1002/2016JG003411/abstract

Spatial and temporal variability of urban fluxes of methane, carbon monoxide and carbon dioxide above London, UK (Helfter et al. 2016) http://www.atmos-chem-phys.net/16/10543/2016/

Climatic variability of the column ozone over the Iranian plateau (Mousavi et al. 2016) http://rd.springer.com/article/10.1007%2Fs00703-016-0474-9

Long-term variation of stratospheric aerosols observed with lidars over Tsukuba, Japan from 1982 and Lauder, New Zealand from 1992 to 2015 (Sakai et al. 2016) http://onlinelibrary.wiley.com/doi/10.1002/2016JD025132/abstract

The natural oscillations in stratospheric ozone observed by the GROMOS microwave radiometer at the NDACC station Bern (Moreira et al. 2016) http://www.atmos-chem-phys.net/16/10455/2016/

A biogenic CO2 flux adjustment scheme for the mitigation of large-scale biases in global atmospheric CO2 analyses and forecasts (Agustí-Panareda et al. 2016) http://www.atmos-chem-phys.net/16/10399/2016/

Relationship of ground-level ozone with synoptic weather conditions in Chicago (Jing et al. 2016) http://www.sciencedirect.com/science/article/pii/S2212095516300335

Global detection of absorbing aerosols over the ocean in the red and near infrared spectral region (Waquet et al. 2016) http://onlinelibrary.wiley.com/doi/10.1002/2016JD025163/abstract

Atmospheric benzene observations from oil and gas production in the Denver Julesburg basin in July and August 2014 (Halliday et al. 2016) http://onlinelibrary.wiley.com/doi/10.1002/2016JD025327/abstract

Carbon monoxide climatology derived from the trajectory mapping of global MOZAIC-IAGOS data (Osman et al. 2016) http://www.atmos-chem-phys.net/16/10263/2016/

Posted in Adaptation & Mitigation, Climate science, Global warming effects | Leave a Comment »

New research – climate change impacts on biosphere (September 14, 2016)

Posted by Ari Jokimäki on September 14, 2016

Some of the latest papers on climate change impacts on biosphere are shown below. First a few highlighted papers with abstracts and then a list of some other papers. If this subject interests you, be sure to check also the other papers – they are by no means less interesting than the highlighted ones.

Highlights

Increasing nest predation will be insufficient to maintain polar bear body condition inthe face of sea-ice loss (Dey et al. 2016) http://onlinelibrary.wiley.com/doi/10.1111/gcb.13499/abstract

Abstract: Climate change can influence interspecific interactions by differentially affecting species-specific phenology. In seasonal ice environments, there is evidence that polar bear predation of Arctic bird eggs is increasing because of earlier sea ice break-up, which forces polar bears into near-shore terrestrial environments where Arctic birds are nesting. Because polar bears can consume a large number of nests before becoming satiated, and because they can swim between island colonies, they could have dramatic influences on seabird and seaduck reproductive success. However, it is unclear whether nest foraging can provide an energetic benefit to polar bear populations, especially given the capacity of bird populations to redistribute in response to increasing predation pressure. In this study, we develop a spatially explicit agent-based model of the predator-prey relationship between polar bears and common eiders, a common and culturally important bird species for northern peoples. Our model is composed of two types of agents (polar bear agents, and common eider hen agents) whose movements and decision heuristics are based on species-specific bioenergetic and behavioral ecological principles, and are influenced by historical and extrapolated sea ice conditions. Our model reproduces empirical findings that polar bear predation of bird nests is increasing, and predicts an accelerating relationship between advancing ice break-up dates and the number of nests depredated. Despite increases in nest predation, our model predicts that polar bear body condition during the ice-free period will continue to decline. Finally, our model predicts that common eider nests will become more dispersed and will move closer to the mainland in response to increasing predation, possibly increasing their exposure to land-based predators, and influencing the livelihood of local people that collect eider eggs and down. These results show that predator-prey interactions can have non-linear responses to changes in climate, and provides important predictions of ecology change in Arctic ecosystems.

Lizards fail to plastically adjust nesting behavior or thermal tolerance as needed to buffer populations from climate warming (Telemaco et al. 2016) http://onlinelibrary.wiley.com/doi/10.1111/gcb.13476/abstract

Abstract: Although observations suggest the potential for phenotypic plasticity to allow adaptive responses to climate change, few experiments have assessed that potential. Modeling suggests that Sceloporus tristichus lizards will need increased nest depth, shade cover, or embryonic thermal tolerance to avoid reproductive failure resulting from climate change. To test for such plasticity, we experimentally examined how maternal temperatures affect nesting behavior and embryonic thermal sensitivity. The temperature regime that females experienced while gravid did not affect nesting behavior, but warmer temperatures at the time of nesting reduced nest depth. Additionally, embryos from heat-stressed mothers displayed increased sensitivity to high-temperature exposure. Simulations suggest that critically low temperatures, rather than high temperatures, historically limit development of our study population. Thus, the plasticity needed to buffer this population has not been under selection. Plasticity will likely fail to compensate for ongoing climate change when such change results in novel stressors.

Adapt, move, or die – how will tropical coral reef fishes cope with ocean warming? (Habary et al. 2016) http://onlinelibrary.wiley.com/doi/10.1111/gcb.13488/abstract

Abstract: Previous studies hailed thermal tolerance and the capacity for organisms to acclimate and adapt as the primary pathways for species survival under climate change. Here we challenge this theory. Over the past decade more than 365 tropical stenothermal fish species have been documented moving pole-ward, away from ocean warming hotspots where temperatures 2-3 °C above long-term annual means can compromise critical physiological processes. We examined the capacity of a model species – a thermally-sensitive coral reef fish, Chromis viridis (Pomacentridae) – to use preference behaviour to regulate its body temperature. Movement could potentially circumvent the physiological stress response associated with elevated temperatures and may be a strategy relied upon before genetic adaptation can be effectuated. Individuals were maintained at one of six temperatures (23, 25, 27, 29, 31 and 33 °C) for at least six weeks. We compared the relative importance of acclimation temperature to changes in upper critical thermal limits, aerobic metabolic scope, and thermal preference. While acclimation temperature positively affected the upper critical thermal limit, neither aerobic metabolic scope nor thermal preference exhibited such plasticity. Importantly, when given the choice to stay in a habitat reflecting their acclimation temperatures or relocate, fish acclimated to end-of-century predicted temperatures (i.e., 31 or 33 °C) preferentially sought out cooler temperatures, those equivalent to long-term summer averages in their natural habitats (~29 °C). This was also the temperature providing the greatest aerobic metabolic scope and body condition across all treatments. Consequently, acclimation can confer plasticity in some performance traits, but may be an unreliable indicator of the ultimate survival and distribution of mobile stenothermal species under global warming. Conversely, thermal preference can arise long before, and remain long after, the harmful effects of elevated ocean temperatures take hold and may be the primary driver of the escalating pole-ward migration of species.

Projections of climate change impacts on central America tropical rainforest (Lyra et al. 2016) http://rd.springer.com/article/10.1007%2Fs10584-016-1790-2

Abstract: Tropical rainforest plays an important role in the global carbon cycle, accounting for a large part of global net primary productivity and contributing to CO2 sequestration. The objective of this work is to simulate potential changes in the rainforest biome in Central America subject to anthropogenic climate change under two emissions scenarios, RCP4.5 and RCP8.5. The use of a dynamic vegetation model and climate change scenarios is an approach to investigate, assess or anticipate how biomes respond to climate change. In this work, the Inland dynamic vegetation model was driven by the Eta regional climate model simulations. These simulations accept boundary conditions from HadGEM2-ES runs in the two emissions scenarios. The possible consequences of regional climate change on vegetation properties, such as biomass, net primary production and changes in forest extent and distribution, were investigated. The Inland model projections show reductions in tropical forest cover in both scenarios. The reduction of tropical forest cover is greater in RCP8.5. The Inland model projects biomass increases where tropical forest remains due to the CO2 fertilization effect. The future distribution of predominant vegetation shows that some areas of tropical rainforest in Central America are replaced by savannah and grassland in RCP4.5. Inland projections under both RCP4.5 and RCP8.5 show a net primary productivity reduction trend due to significant tropical forest reduction, temperature increase, precipitation reduction and dry spell increments, despite the biomass increases in some areas of Costa Rica and Panama. This study may provide guidance to adaptation studies of climate change impacts on the tropical rainforests in Central America.

Interactive effects of temperature and pCO2 on sponges: from the cradle to the grave (Bennett et al. 2016) http://onlinelibrary.wiley.com/doi/10.1111/gcb.13474/abstract

Abstract: As atmospheric CO2 concentrations rise, associated ocean warming (OW) and ocean acidification (OA) are predicted to cause declines in reef-building corals globally, shifting reefs from coral-dominated systems to those dominated by less sensitive species. Sponges are important structural and functional components of coral reef ecosystems, but despite increasing field based evidence that sponges may be ‘winners’ in response to environmental degradation, our understanding of how they respond to the combined effects of OW and OA is limited. To determine the tolerance of adult sponges to climate change, four abundant Great Barrier Reef species were experimentally exposed to OW and OA levels predicted for 2100, under two CO2 Representative Concentration Pathways (RCPs). The impact of OW and OA on early life history stages was also assessed for one of these species to provide a more holistic view of species impacts. All species were generally unaffected by conditions predicted under RCP6.0, although environmental conditions projected under RCP8.5 caused significant adverse effects; with elevated temperature decreasing the survival of all species, increasing levels of tissue necrosis and bleaching, elevating respiration rates and decreasing photosynthetic rates. OA alone had little adverse effect, even under RCP8.5 concentrations. Importantly, the interactive effect of OW and OA varied between species with different nutritional modes, with elevated pCO2 exacerbating temperature stress in heterotrophic species but mitigating temperature stress in phototrophic species. This antagonistic interaction was reflected by reduced mortality, necrosis and bleaching of phototrophic species in the highest OW/OA treatment. Survival and settlement success of C. foliascens larvae were unaffected by experimental treatments, and juvenile sponges exhibited greater tolerance to OW than their adult counterparts. With elevated pCO2 providing phototrophic species with protection from elevated temperature, across different life-stages, climate change may ultimately drive a shift in the composition of sponge assemblages towards a dominance of phototrophic species.

Other papers

Stability in a changing world – palm community dynamics in the hyperdiverse western Amazon over 17 years (Olivares et al. 2016) http://onlinelibrary.wiley.com/doi/10.1111/gcb.13494/abstract

Recent climate hiatus revealed dual control by temperature and drought on the stem growth of Mediterranean Quercus ilex (Lempereur et al. 2016) http://onlinelibrary.wiley.com/doi/10.1111/gcb.13495/abstract

Environmental constraints on Holocene cold-water coral reef growth off Norway: Insights from a multi-proxy approach (Raddatz et al. 2016) http://onlinelibrary.wiley.com/doi/10.1002/2016PA002974/abstract

Projected shifts in fish species dominance in Wisconsin lakes under climate change (Hansen et al. 2016) http://onlinelibrary.wiley.com/doi/10.1111/gcb.13462/abstract

Phenological research of climate changes in the north part of Lithuania by the phenological garden of Šiauliai University (Klimienė et al. 2016) http://rd.springer.com/article/10.1007%2Fs00484-016-1211-2

Stream network geomorphology mediates predicted vulnerability of anadromous fish habitat to hydrologic change in southeast Alaska (Sloat et al. 2016) http://onlinelibrary.wiley.com/doi/10.1111/gcb.13466/abstract

Diatom assemblages reveal regional-scale differences in lake responses to recent climate change at the boreal-tundra ecotone, Manitoba, Canada (Shinneman et al. 2016) http://rd.springer.com/article/10.1007%2Fs10933-016-9911-5

Temperature sensitivity thresholds to warming and cooling in phenophases of alpine plants (Meng et al. 2016) http://rd.springer.com/article/10.1007%2Fs10584-016-1802-2

Relationships between climate, topography, water use and productivity in two key Mediterranean forest types with different water-use strategies (Helman et al. 2016) http://www.sciencedirect.com/science/article/pii/S0168192316303732

Ant assemblages have darker and larger members in cold environments (Bishop et al. 2016) http://onlinelibrary.wiley.com/doi/10.1111/geb.12516/abstract

Spring blooms in the Baltic Sea have weakened but lengthened from 2000 to 2014 (Groetsch et al. 2016) http://www.biogeosciences.net/13/4959/2016/

Current and projected global distribution of Phytophthora cinnamomi, one of the world’s worst plant pathogens (Burgess et al. 2016) http://onlinelibrary.wiley.com/doi/10.1111/gcb.13492/abstract

Assessing drought-driven mortality trees with physiological process-based models (Hendrik & Maxime, 2016) http://www.sciencedirect.com/science/article/pii/S0168192316303744

Global patterns in lake ecosystem responses to warming based on the temperature dependence of metabolism (Kraemer et al. 2016) http://onlinelibrary.wiley.com/doi/10.1111/gcb.13459/abstract

Additive effects of temperature and infection with an acanthocephalan parasite on the shredding activity of Gammarus fossarum (Crustacea: Amphipoda): the importance of aggregative behavior (Labaude et al. 2016) http://onlinelibrary.wiley.com/doi/10.1111/gcb.13490/abstract

Growth of northern deciduous trees under increasing atmospheric humidity: possible mechanisms behind the growth retardation (Sellin et al. 2016) http://rd.springer.com/article/10.1007%2Fs10113-016-1042-z

Responses of net primary productivity to phenological dynamics in the Tibetan Plateau, China (Wang et al. 2016) http://www.sciencedirect.com/science/article/pii/S0168192316303756

Variation in White Stork (Ciconia ciconia) diet along a climatic gradient and across rural-to-urban landscapes in North Africa (Chenchouni, 2016) http://rd.springer.com/article/10.1007%2Fs00484-016-1232-x

Species-specific responses to climate change and community composition determine future calcification rates of Florida Keys reefs (Okazaki et al. 2016) http://onlinelibrary.wiley.com/doi/10.1111/gcb.13481/abstract

Aleppo pine forests from across Spain show drought-induced growth decline and partial recovery (Gazol et al. 2016) http://www.sciencedirect.com/science/article/pii/S0168192316303690

Climate change will increase the naturalization risk from garden plants in Europe (Dullinger et al. 2016) http://onlinelibrary.wiley.com/doi/10.1111/geb.12512/abstract

Coarse climate change projections for species living in a fine-scaled world (Nadeau et al. 2016) http://onlinelibrary.wiley.com/doi/10.1111/gcb.13475/abstract

Confounding effects of spatial variation on shifts in phenology (de Keyzer et al. 2016) http://onlinelibrary.wiley.com/doi/10.1111/gcb.13472/abstract

Climate warming reduces fish production and benthic habitat in Lake Tanganyika, one of the most biodiverse freshwater ecosystems (Cohen et al. 2016) http://www.pnas.org/content/113/34/9563.short

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Papers on micro-organisms in permafrost

Posted by Ari Jokimäki on September 13, 2016

This is a list of papers on micro-organisms in permafrost. The list is not complete, and will most likely be updated in future in order to make it more thorough and more representative.

Functional Characterization of Bacteria Isolated from Ancient Arctic Soil Exposes Diverse Resistance Mechanisms to Modern Antibiotics (Perron et al. 2015) [FULL TEXT]
Abstract: “Using functional metagenomics to study the resistomes of bacterial communities isolated from different layers of the Canadian high Arctic permafrost, we show that microbial communities harbored diverse resistance mechanisms at least 5,000 years ago. Among bacteria sampled from the ancient layers of a permafrost core, we isolated eight genes conferring clinical levels of resistance against aminoglycoside, β-lactam and tetracycline antibiotics that are naturally produced by microorganisms. Among these resistance genes, four also conferred resistance against amikacin, a modern semi-synthetic antibiotic that does not naturally occur in microorganisms. In bacteria sampled from the overlaying active layer, we isolated ten different genes conferring resistance to all six antibiotics tested in this study, including aminoglycoside, β-lactam and tetracycline variants that are naturally produced by microorganisms as well as semi-synthetic variants produced in the laboratory. On average, we found that resistance genes found in permafrost bacteria conferred lower levels of resistance against clinically relevant antibiotics than resistance genes sampled from the active layer. Our results demonstrate that antibiotic resistance genes were functionally diverse prior to the anthropogenic use of antibiotics, contributing to the evolution of natural reservoirs of resistance genes.”
Citation: Perron GG, Whyte L, Turnbaugh PJ, Goordial J, Hanage WP, Dantas G, et al. (2015) Functional Characterization of Bacteria Isolated from Ancient Arctic Soil Exposes Diverse Resistance Mechanisms to Modern Antibiotics. PLoS ONE 10(3): e0069533. doi:10.1371/journal.pone.0069533.

Molecular characterization of bacteria from permafrost of the Taylor Valley, Antarctica (Bakermans et al. 2014) [FULL TEXT]
Abstract: “While bacterial communities from McMurdo Dry Valley soils have been studied using molecular techniques, data from permafrost are particularly scarce given the logistical difficulties of sampling. This study examined the molecular diversity and culturability of bacteria in permafrost from the Taylor Valley (TV), Antarctica. A 16S rRNA gene clone library was constructed to assess bacterial diversity, while a clone library of the RNA polymerase beta subunit (rpoB) gene was constructed to examine amino acid composition of an essential protein-coding gene. The 16S rRNA gene clone library was dominated by Acidobacteria from Gp6 and Gemmatimonadetes. The rpoB gene clone library (created with primers designed in this study) was also dominated by Acidobacteria. The ability of sequence analyses to garner additional information about organisms represented by TV sequences was explored. Specifically, optimum growth temperature was estimated from the stem GC content of the 16S rRNA gene, while potential cold adaptations within translated rpoB sequences were assessed. These analyses were benchmarked using known psychrophiles and mesophiles. Bioinformatic analyses suggested that many TV sequences could represent organisms capable of activity at low temperatures. Plate counts confirmed that c. 103 cells per gram permafrost remained viable and were culturable, while laboratory respiration assays demonstrated that microbial activity occurred at −5 °C and peaked at 15 °C.”
Citation: Bakermans, C., Skidmore, M. L., Douglas, S. and McKay, C. P. (2014), Molecular characterization of bacteria from permafrost of the Taylor Valley, Antarctica. FEMS Microbiol Ecol, 89: 331–346. doi:10.1111/1574-6941.12310.

Bacterial growth at −15 °C; molecular insights from the permafrost bacterium Planococcus halocryophilus Or1 (Mykytczuk et al. 2013) [FULL TEXT]
Abstract: “Planococcus halocryophilus strain Or1, isolated from high Arctic permafrost, grows and divides at −15 °C, the lowest temperature demonstrated to date, and is metabolically active at −25 °C in frozen permafrost microcosms. To understand how P. halocryophilus Or1 remains active under the subzero and osmotically dynamic conditions that characterize its native permafrost habitat, we investigated the genome, cell physiology and transcriptomes of growth at −15 °C and 18% NaCl compared with optimal (25 °C) temperatures. Subzero growth coincides with unusual cell envelope features of encrustations surrounding cells, while the cytoplasmic membrane is significantly remodeled favouring a higher ratio of saturated to branched fatty acids. Analyses of the 3.4 Mbp genome revealed that a suite of cold and osmotic-specific adaptive mechanisms are present as well as an amino acid distribution favouring increased flexibility of proteins. Genomic redundancy within 17% of the genome could enable P. halocryophilus Or1 to exploit isozyme exchange to maintain growth under stress, including multiple copies of osmolyte uptake genes (Opu and Pro genes). Isozyme exchange was observed between the transcriptome data sets, with selective upregulation of multi-copy genes involved in cell division, fatty acid synthesis, solute binding, oxidative stress response and transcriptional regulation. The combination of protein flexibility, resource efficiency, genomic plasticity and synergistic adaptation likely compensate against osmotic and cold stresses. These results suggest that non-spore forming P. halocryophilus Or1 is specifically suited for active growth in its Arctic permafrost habitat (ambient temp. ~−16 °C), indicating that such cryoenvironments harbor a more active microbial ecosystem than previously thought.”
Citation: Nadia C S Mykytczuk, Simon J Foote, Chris R Omelon, Gordon Southam, Charles W Greer, Lyle G Whyte, The ISME Journal (2013) 7, 1211–1226; doi:10.1038/ismej.2013.8.

Climate change and zoonotic infections in the Russian Arctic (Revich et al. 2012) [FULL TEXT]
Abstract: “Climate change in the Russian Arctic is more pronounced than in any other part of the country. Between 1955 and 2000, the annual average air temperature in the Russian North increased by 1.2°C. During the same period, the mean temperature of upper layer of permafrost increased by 3°C. Climate change in Russian Arctic increases the risks of the emergence of zoonotic infectious diseases. This review presents data on morbidity rates among people, domestic animals and wildlife in the Russian Arctic, focusing on the potential climate related emergence of such diseases as tick-borne encephalitis, tularemia, brucellosis, leptospirosis, rabies, and anthrax.”
Citation: Boris Revich, Nikolai Tokarevich, Alan J. Parkinson, Int J Circumpolar Health 2012, 71: 18792 – http://dx.doi.org/10.3402/ijch.v71i0.18792.

On the prospects of microbiological research on mammoth fauna in permafrost (Neustroev, 2012)
Abstract: “Research of mammoth microflora is of current interest in terms of psychrophiles, cryoanabiosis, and the peculiar properties of ecology and evolution of microorganisms. Recovered Bacillus bacteria strains of the mammoths express antagonistic activity against pathogenic and opportunistic microorganisms. Moreover, the strains are antibiotic resistant and salt tolerant. The obtained data is consistent with research on biocoenosis of domestic and wild animals, cryogenic soil, air, atmosphere precipitation, and plants. Having high biological activity, Bacillus bacteria are the dominant group in the microbiocenosis environment in permafrost.”
Citation: M.P. Neustroev, Quaternary International, Volume 255, 26 March 2012, Pages 139–140, http://dx.doi.org/10.1016/j.quaint.2011.06.003.

43. Global warming and expanding the range of feral conditions in Yakutia – The coldest region of the North-East Asia (Solomonov et al. 2012)
Abstract: “In Yakutia, there has long been a number of natural foci of infectious human and animal diseases such as tularemia, anthrax, rabies, brucellosis, leptospirosis and others. The circulation of pathogens in nature is closely connected with the peculiarities of natural ecosystems and their animal populations, especially the mass species of birds and mammals and their ecto-and endoparasites. Global warming has caused the expansion to the north of the range of many species of birds and their ectoparasites from the southern parts of the Asia–Pacific region. There was the possibility of the spread causative agent of avian influenza H5N1 dangerous to humans, in-line with those observed in recent decades, global warming and the expansion of the range of animal-carriers and custodians of infectious agents are expanding the range of feral diseases such as rabies, brucellosis,and encephalitis, stable foci of new diseases, including pseudotuberculosis, have appeared in our region. With further advancement of the classical forms of rabies in South Yakutia in the central and northern areas of the Arctic, the counter-propagation form of rabies may occur to the south, with the genetic restructuring of their agents as a result of recombination of genes and new mutations. Melting of permafrost soils and an irrigation of territories can promote “awakening” of the centres, previously widespread in the region, of a malignant anthrax and natural smallpox. There is concern has about the recently established detection of viable, including spore-forming, micro-organisms in the remains of the mammoth fauna of the natural burial sites in the Late Pleistocene permafrost sediments over time. The latter indicates that there is potential for the release of pathogens from the surface of especially dangerous infections from that era (epidemiological echo). Previously, Somov (1974), who worked many years in Chukotka and other regions of the Russian Far East, put forward a hypothesis on the preservation of psychrophilic pathogens infections at low temperatures of the environment in saprophytic state that only if it enters the human body become virulent. In this regard, we suggested in 1980 that “the further development of the northern territories may appear natural foci of new, perhaps previously unknown infectious diseases”. Thus, global warming contributes to increased incidence of especially dangerous infections by expanding the range of animal carriers and disseminators of infection due to possible preservation at low temperatures in the state of saprophytic pathogens in the active state.”
Citation: N.G. Solomonov, V.F. Chernyavskyy, B.M. Kerschengoltz, O.I. Nikiphorov, E.S. Khlebnyy, Cryobiology, Volume 65, Issue 3, December 2012, Pages 353, http://dx.doi.org/10.1016/j.cryobiol.2012.07.044.

Thawing of permafrost may disturb historic cattle burial grounds in East Siberia (Revich & Podolnaya, 2011) [FULL TEXT]
Abstract: “Climate warming in the Arctic may increase the risk of zoonoses due to expansion of vector habitats, improved chances of vector survival during winter, and permafrost degradation. Monitoring of soil temperatures at Siberian cryology control stations since 1970 showed correlations between air temperatures and the depth of permafrost layer that thawed during summer season. Between 1900s and 1980s, the temperature of surface layer of permafrost increased by 2–4°C; and a further increase of 3°C is expected. Frequent outbreaks of anthrax caused death of 1.5 million deer in Russian North between 1897 and 1925. Anthrax among people or cattle has been reported in 29,000 settlements of the Russian North, including more than 200 Yakutia settlements, which are located near the burial grounds of cattle that died from anthrax. Statistically significant positive trends in annual average temperatures were established in 8 out of 17 administrative districts of Yakutia for which sufficient meteorological data were available. At present, it is not known whether further warming of the permafrost will lead to the release of viable anthrax organisms. Nevertheless, we suggest that it would be prudent to undertake careful monitoring of permafrost conditions in all areas where an anthrax outbreak had occurred in the past.”
Citation: Boris A. Revich, Marina A. Podolnaya, Global Health Action 2011, 4: 8482 – DOI: 10.3402/gha.v4i0.8482.

Biogeochemistry of permafrost in Central Yakutia (Brouchkov et al. 2011) [FULL TEXT]
Abstract: “Permafrost is widespread in the Northern Hemisphere and is as old as hundreds of thousands to millions of years. Frozen ground stores living microorganisms which remain unfrozen in the relatively warm environment (–2…–8 °C) but are immobilized and may be about the age of the host permafrost. A strain of Bacillus sp. was isolated from ~3 Ma permafrost and its 16S rDNA sequence was identified. A large group of microorganisms including fungi was isolated from the wedge ice. Permafrost deposits contain invertase, urease, katalase and dehydrogenase.”
Citation: A.V. Brouchkov, V.P. Melnikov, M.V. Schelchkova, G.I. Griva, V.E. Repin, E.V. Brenner, M. Tanaka, EARTH CRYOSPHERE, 2011, Vol. XV, № 4, p. 79-87.

Multi-locus real-time PCR for quantitation of bacteria in the environment reveals Exiguobacterium to be prevalent in permafrost (Rodrigues & Tiedje, 2007) [FULL TEXT]
Abstract: “We developed a multi-locus quantitative PCR approach to minimize problems of precision, sensitivity and primer specificity for quantifying a targeted microbial group in nature. This approach also avoids a systematic error in population quantitation when 16S rRNA genes are used because of copy number heterogeneity. Specific primers were designed to assess the abundance of psychrotrophic and mesophilic Exiguobacterium spp. that excluded the thermophilic members of the genus. The chosen primers targeted genes for DNA gyrase B (gyrB), the beta subunit of the RNA polymerase gene (rpoB) and a hypothetical gene so far found only in this group. The results demonstrate that the multiple primer approach provides a more reliable estimate of population density; that the targeted Exiguobacterium group is found at a median density of 50 000 gene copies per μg of total community DNA in 27 of 29 permafrost soils but was found in only one of the four temperate and tropical soils tested.”
Citation: Rodrigues, D. F. and Tiedje, J. M. (2007), Multi-locus real-time PCR for quantitation of bacteria in the environment reveals Exiguobacterium to be prevalent in permafrost. FEMS Microbiology Ecology, 59: 489–499. doi:10.1111/j.1574-6941.2006.00233.x.

Diversity and distribution of alkaliphilic psychrotolerant bacteria in the Qinghai–Tibet Plateau permafrost region (Zhang et al. 2007)
Abstract: “The Qinghai–Tibet Plateau represents a unique permafrost environment, being a result of high elevation caused by land uplift. And the urgency was that plateau permafrost was degrading rapidly under the current predicted climatic warming scenarios. Hence, the permafrost there was sampled to recover alkaliphilic bacteria populations. The viable bacteria on modified PYGV agar were varied between 102 and 105 CFU/g of dry soil. Forty-eight strains were gained from 18 samples. Through amplified ribosomal DNA restriction analysis (ARDRA) and phylogenetic analyses, these isolates fell into three categories: high G + C gram positive bacteria (82.3%), low G + C gram positive bacteria (7.2%), and gram negative α-proteobacteria (10.5%). The strains could grow at pH values ranging from 6.5 to 10.5 with optimum pH in the range of 9–9.5. Their growth temperatures were below 37°C and the optima ranging from 10 to 15°C. All strains grew well when NaCl concentration was below 15%. These results indicate that there are populations of nonhalophilic alkaliphilic psychrotolerant bacteria within the permafrost of the Qinhai-Tibet plateau. The abilities of many of the strains to produce extracellular protease, amylase and cellulase suggest that they might be of potential value for biotechnological exploitation.”
Citation: Zhang, G., Ma, X., Niu, F. et al. Extremophiles (2007) 11: 415. doi:10.1007/s00792-006-0055-9.

Characterization of the microbial diversity in a permafrost sample from the Canadian high Arctic using culture-dependent and culture-independent methods (Steven et al. 2007) [FULL TEXT]
Abstract: “A combination of culture-dependent and culture-independent methodologies (Bacteria and Archaea 16S rRNA gene clone library analyses) was used to determine the microbial diversity present within a geographically distinct high Arctic permafrost sample. Culturable Bacteria isolates, identified by 16S rRNA gene sequencing, belonged to the phyla Firmicutes, Actinobacteria and Proteobacteria with spore-forming Firmicutes being the most abundant; the majority of the isolates (19/23) were psychrotolerant, some (11/23) were halotolerant, and three isolates grew at −5°C. A Bacteria 16S rRNA gene library containing 101 clones was composed of 42 phylotypes related to diverse phylogenetic groups including the Actinobacteria, Proteobacteria, Firmicutes, Cytophaga – Flavobacteria – Bacteroides, Planctomyces and Gemmatimonadetes; the bacterial 16S rRNA gene phylotypes were dominated by Actinobacteria- and Proteobacteria-related sequences. An Archaea 16S rRNA gene clone library containing 56 clones was made up of 11 phylotypes and contained sequences related to both of the major Archaea domains (Euryarchaeota and Crenarchaeota); the majority of sequences in the Archaea library were related to halophilic Archaea. Characterization of the microbial diversity existing within permafrost environments is important as it will lead to a better understanding of how microorganisms function and survive in such extreme cryoenvironments.”
Citation: Steven, B., Briggs, G., McKay, C. P., Pollard, W. H., Greer, C. W. and Whyte, L. G. (2007), Characterization of the microbial diversity in a permafrost sample from the Canadian high Arctic using culture-dependent and culture-independent methods. FEMS Microbiology Ecology, 59: 513–523. doi:10.1111/j.1574-6941.2006.00247.x.

Microbial ecology and biodiversity in permafrost (Steven et al. 2006) [FULL TEXT]
Abstract: “Permafrost represents 26% of terrestrial soil ecosystems; yet its biology, essentially microbiology, remains relatively unexplored. The permafrost environment is considered extreme because indigenous microorganisms must survive prolonged exposure to subzero temperatures and background radiation for geological time scales in a habitat with low water activity and extremely low rates of nutrient and metabolite transfer. Yet considerable numbers and biodiversity of bacteria exist in permafrost, some of which may be among the most ancient viable life on Earth. This review describes the permafrost environment as a microbial habitat and reviews recent studies examining microbial biodiversity found in permafrost as well as microbial growth and activity at ambient in situ subzero temperatures. These investigations suggest that functional microbial ecosystems exist within the permafrost environment and may have important implications on global biogeochemical processes as well as the search for past or extant life in permafrost presumably present on Mars and other bodies in our solar system.”
Citation: Steven, B., Léveillé, R., Pollard, W.H. et al. Extremophiles (2006) 10: 259. doi:10.1007/s00792-006-0506-3.

Characterization of potential stress responses in ancient Siberian permafrost psychroactive bacteria (Ponder et al. 2005) [FULL TEXT]
Abstract: “Past studies of cold-acclimated bacteria have focused primarily on organisms not capable of sub-zero growth. Siberian permafrost isolates Exiguobacterium sp. 255-15 and Psychrobacter sp. 273-4, which grow at subzero temperatures, were used to study cold-acclimated physiology. Changes in membrane composition and exopolysaccharides were defined as a function of growth at 24, 4 and −2.5 °C in the presence and absence of 5% NaCl. As expected, there was a decrease in fatty acid saturation and chain length at the colder temperatures and a further decrease in the degree of saturation at higher osmolarity. A shift in carbon source utilization and antibiotic resistance occurred at 4 versus 24 °C growth, perhaps due to changes in the membrane transport. Some carbon substrates were used uniquely at 4 °C and, in general, increased antibiotic sensitivity was observed at 4 °C. All the permafrost strains tested were resistant to long-term freezing (1 year) and were not particularly unique in their UVC tolerance. Most of the tested isolates had moderate ice nucleation activity, and particularly interesting was the fact that the Gram-positive Exiguobacterium showed some soluble ice nucleation activity. In general the features measured suggest that the Siberian organisms have adapted to the conditions of long-term freezing at least for the temperatures of the Kolyma region which are −10 to −12 °C where intracellular water is likely not frozen.”
Citation: Monica A. Ponder, Sarah J. Gilmour, Peter W. Bergholz, Carol A. Mindock, Rawle Hollingsworth, Michael F. Thomashow, James M. Tiedje, FEMS Microbiology Ecology, Volume 53, Issue 1, Pp. 103 – 115, DOI: http://dx.doi.org/10.1016/j.femsec.2004.12.003.

Long-term persistence of bacterial DNA (Willerslev et al. 2004) [FULL TEXT]
Abstract: “The persistence of bacterial DNA over geological timespans remains a contentious issue. In direct contrast to in vitro based predictions, bacterial DNA and even culturable cells have been reported from various ancient specimens many million years (Ma) old. As both ancient DNA studies and the revival of microorganisms are known to be susceptible to contamination, it is concerning that these results have not been independently replicated to confirm their authenticity. Furthermore, they show no obvious relationship between sample age, and either bacterial composition or DNA persistence, although bacteria are known to differ markedly in hardiness and resistance to DNA degradation. We present the first study of DNA durability and degradation of a broad variety of bacteria preserved under optimal frozen conditions, using rigorous ancient DNA methods. The results demonstrate that non-spore-forming gram-positive (GP) Actinobacteria are by far the most durable, out-surviving endospore-formers such as Bacillaceae and Clostridiaceae. The observed DNA degradation rates are close to theoretical calculations, indicating a limit of ca. 400 thousand years (kyr) beyond which PCR amplifications are prevented by the formation of DNA interstrand crosslinks (ICLs).”
Citation: Eske Willerslev, Anders J. Hansen, Regin Rønn, Tina B. Brand, Ian Barnes, Carsten Wiuf, David Gilichinsky, David Mitchell, Alan Cooper, Current Biology, Volume 14, Issue 1, 6 January 2004, Pages R9–R10, http://dx.doi.org/10.1016/j.cub.2003.12.012.

Reproduction and metabolism at − 10°C of bacteria isolated from Siberian permafrost (Bakermans et al. 2003) [FULL TEXT]
Abstract: “We report the isolation and properties of several species of bacteria from Siberian permafrost. Half of the isolates were spore-forming bacteria unable to grow or metabolize at subzero temperatures. Other Gram-positive isolates metabolized, but never exhibited any growth at − 10°C. One Gram-negative isolate metabolized and grew at − 10°C, with a measured doubling time of 39 days. Metabolic studies of several isolates suggested that as temperature decreased below + 4°C, the partitioning of energy changes with much more energy being used for cell maintenance as the temperature decreases. In addition, cells grown at − 10°C exhibited major morphological changes at the ultrastructural level.”
Citation: Bakermans, C., Tsapin, A. I., Souza-Egipsy, V., Gilichinsky, D. A. and Nealson, K. H. (2003), Reproduction and metabolism at − 10°C of bacteria isolated from Siberian permafrost. Environmental Microbiology, 5: 321–326. doi:10.1046/j.1462-2920.2003.00419.x.

Low-temperature recovery strategies for the isolation of bacteria from ancient permafrost sediments (Vishnivetskaya et al. 2000) [FULL TEXT]
Abstract: “Permafrost represents a unique ecosystem that has allowed the prolonged survival of certain bacterial lineages at subzero temperatures. To better understand the permafrost microbial community, it is important to identify isolation protocols that optimize the recovery of genetically diverse bacterial lineages. We have investigated the impact of different low-temperature isolation protocols on recovery of aerobic bacteria from northeast Siberian permafrost of variable geologic origin and frozen for 5000 to 3 million years. Low-nutrient media enhanced the quantitative recovery of bacteria, whereas the isolation of diverse morphotypes was maximized on rich media. Cold enrichments done directly in natural, undisturbed permafrost led not only to recovery of increased numbers of bacteria but also to isolation of genotypes not recovered by means of liquid low-temperature enrichments. On the other hand, direct plating and growth at 4°C also led to recovery of diverse genotypes, some of which were not recovered following enrichment. Strains recovered from different permafrost samples were predominantly oligotrophic and non-spore-forming but were otherwise variable from each other in terms of a number of bacteriological characteristics. Our data suggest that a combination of isolation protocols from different permafrost samples should be used to establish a culture-based survey of the different bacterial lineages in permafrost.”
Citation: Vishnivetskaya, T., Kathariou, S., McGrath, J. et al. Extremophiles (2000) 4: 165. doi:10.1007/s007920070031.

Metabolic Activity of Permafrost Bacteria below the Freezing Point (Rivkina et al. 2000) [FULL TEXT]
Abstract: “Metabolic activity was measured in the laboratory at temperatures between 5 and −20°C on the basis of incorporation of14C-labeled acetate into lipids by samples of a natural population of bacteria from Siberian permafrost (permanently frozen soil). Incorporation followed a sigmoidal pattern similar to growth curves. At all temperatures, the log phase was followed, within 200 to 350 days, by a stationary phase, which was monitored until the 550th day of activity. The minimum doubling times ranged from 1 day (5°C) to 20 days (−10°C) to ca. 160 days (−20°C). The curves reached the stationary phase at different levels, depending on the incubation temperature. We suggest that the stationary phase, which is generally considered to be reached when the availability of nutrients becomes limiting, was brought on under our conditions by the formation of diffusion barriers in the thin layers of unfrozen water known to be present in permafrost soils, the thickness of which depends on temperature.”
Citation: E. M. Rivkina, E. I. Friedmann, C. P. McKay, D. A. Gilichinsky, Appl. Environ. Microbiol. August 2000 vol. 66 no. 8 3230-3233, doi: 10.1128/AEM.66.8.3230-3233.2000.

Hygienic problems in using permafrost soils for organic waste disposal (Bölter & Höller, 1999) [FULL TEXT]
Abstract: “This paper reviews the risks on hygienic problems in the northern environments by reindeer slaughter and related waste disposals. Such risks are evident from anticipated possible changes in the socio-economic structure in this region and changes in land use and animal keeping. There are several problems going along with different pathogens and their infection ways. Precautions have to be taken especially for those organisms which can live for long times under dormant stages or which form spores.”
Citation: Manfred Bölter, Christiane Höller, Polarforschung 66 (1/2),61 – 65,1996 (erschienen 1999).

Characterization of Viable Bacteria from Siberian Permafrost by 16S rDNA Sequencing (Shi et al. 1997) [FULL TEXT]
Abstract: “Viable bacteria were found in permafrost core samples from the Kolyma-Indigirka lowland of northeast Siberia. The samples were obtained at different depths; the deepest was about 3 million years old. The average temperature of the permafrost is −10°C. Twenty-nine bacterial isolates were characterized by 16S rDNA sequencing and phylogenetic analysis, cell morphology, Gram staining, endospore formation, and growth at 30°C. The majority of the bacterial isolates were rod shaped and grew well at 30°C; but two of them did not grow at or above 28°C, and had optimum growth temperatures around 20°C. Thirty percent of the isolates could form endospores. Phylogenetic analysis revealed that the isolates fell into four categories: high-GC Gram-positive bacteria, β-proteobacteria, γ-proteobacteria, and low-GC Gram-positive bacteria. Most high-GC Gram-positive bacteria and β-proteobacteria, and all γ-proteobacteria, came from samples with an estimated age of 1.8–3.0 million years (Olyor suite). Most low-GC Gram-positive bacteria came from samples with an estimated age of 5,000–8,000 years (Alas suite).”
Citation: Shi, T., Reeves, R., Gilichinsky, D. et al. Microb Ecol (1997) 33: 169. doi:10.1007/s002489900019.

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New research – carbon cycle (September 12, 2016)

Posted by Ari Jokimäki on September 12, 2016

Some of the latest papers on carbon cycle are shown below. First a few highlighted papers with abstracts and then a list of some other papers. If this subject interests you, be sure to check also the other papers – they are by no means less interesting than the highlighted ones.

Highlights

Methane emissions proportional to permafrost carbon thawed in Arctic lakes since the 1950s (Anthony et al. 2016) http://www.nature.com/ngeo/journal/vaop/ncurrent/full/ngeo2795.html

Abstract: Permafrost thaw exposes previously frozen soil organic matter to microbial decomposition. This process generates methane and carbon dioxide, and thereby fuels a positive feedback process that leads to further warming and thaw. Despite widespread permafrost degradation during the past ~40 years, the degree to which permafrost thaw may be contributing to a feedback between warming and thaw in recent decades is not well understood. Radiocarbon evidence of modern emissions of ancient permafrost carbon is also sparse. Here we combine radiocarbon dating of lake bubble trace-gas methane (113 measurements) and soil organic carbon (289 measurements) for lakes in Alaska, Canada, Sweden and Siberia with numerical modelling of thaw and remote sensing of thermokarst shore expansion. Methane emissions from thermokarst areas of lakes that have expanded over the past 60 years were directly proportional to the mass of soil carbon inputs to the lakes from the erosion of thawing permafrost. Radiocarbon dating indicates that methane age from lakes is nearly identical to the age of permafrost soil carbon thawing around them. Based on this evidence of landscape-scale permafrost carbon feedback, we estimate that 0.2 to 2.5 Pg permafrost carbon was released as methane and carbon dioxide in thermokarst expansion zones of pan-Arctic lakes during the past 60 years.

Rising Plant-mediated Methane Emissions from Arctic Wetlands (Andresen et al. 2016) http://onlinelibrary.wiley.com/doi/10.1111/gcb.13469/abstract

Abstract: Plant-mediated CH4 flux is an important pathway for land-atmosphere CH4 emissions but the magnitude, timing, and environmental controls, spanning scales of space and time, remain poorly understood in arctic tundra wetlands, particularly under the long term effects of climate change. CH4 fluxes were measured in situ during peak growing season for the dominant aquatic emergent plants in the Alaskan arctic coastal plain, Carex aquatilis and Arctophila fulva, to assess the magnitude and species-specific controls on CH4 flux. Plant biomass was a strong predictor of A. fulva CH4 flux while water depth and thaw depth were co-predictors for C. aquatilis CH4 flux. We used plant and environmental data from 1971-72 from the historic International Biological Program (IBP) research site near Barrow, Alaska, which we resampled in 2010-13, to quantify changes in plant biomass and thaw depth, and used these to estimate species-specific decadal-scale changes in CH4 fluxes. A ~60% increase in CH4 flux was estimated from the observed plant biomass and thaw depth increases in tundra ponds over the past 40 years. Despite covering only ~5% of the landscape, we estimate that aquatic C. aquatilis and A. fulva account for two-thirds of the total regional CH4 flux of the Barrow Peninsula. The regionally observed increases in plant biomass and active layer thickening over the past 40 years not only have major implications for energy and water balance, but have significantly altered land-atmosphere CH4 emissions for this region, potentially acting as a positive feedback to climate warming.

Enhanced carbon export to the abyssal depths driven by atmosphere dynamics (Pedrosa-Pàmies et al. 2016) http://onlinelibrary.wiley.com/doi/10.1002/2016GL069781/abstract

Abstract: Long-term biogeochemical observations are critical to understand the natural ability of the oceans to fix CO2 into organic carbon and export it to the deep as sinking particles. Here we present results from a 3 year (2010–2013) sediment trap deployment that allowed detecting interannual variations of carbon fluxes beyond 4000 m depth in the Eastern Mediterranean Sea. Anomalous atmospheric conditions triggering strong heat losses in winter–spring 2012 resulted in convective mixing, nutrient uplifting, and a diatom-dominated bloom southeast of Crete. Phytoplankton growth, reinforced by the arrival of nutrients from airborne Etna volcano ash, was the highest in the last decade (satellite-derived Chl a concentrations up to 1.9 mg m−3). This situation caused carbon export to increase by 2 orders of magnitude (12.2 mg m−2 d−1) with respect to typical values, which demonstrates how pulses of sinking fresh phytodetritus linked to rare atmospheric processes can episodically impact one of the most oligotrophic environments in the world ocean.

Partitioning uncertainty in ocean carbon uptake projections: Internal variability, emission scenario, and model structure (Lovenduski et al. 2016) http://onlinelibrary.wiley.com/doi/10.1002/2016GB005426/abstract

Abstract: We quantify and isolate the sources of projection uncertainty in annual-mean sea-air CO2 flux over the period 2006–2080 on global and regional scales using output from two sets of ensembles with the Community Earth System Model (CESM) and models participating in the 5th Coupled Model Intercomparison Project (CMIP5). For annual-mean, globally-integrated sea-air CO2 flux, uncertainty grows with prediction lead time and is primarily attributed to uncertainty in emission scenario. At the regional scale of the California Current System, we observe relatively high uncertainty that is nearly constant for all prediction lead times, and is dominated by internal climate variability and model structure, respectively in the CESM and CMIP5 model suites. Analysis of CO2 flux projections over 17 biogeographical biomes reveals a spatially heterogenous pattern of projection uncertainty. On the biome scale, uncertainty is driven by a combination of internal climate variability and model structure, with emission scenario emerging as the dominant source for long projection lead times in both modeling suites.

The sensitivity of soil respiration to soil temperature, moisture, and carbon supply at the global scale (Hursh et al. 2016) http://onlinelibrary.wiley.com/doi/10.1111/gcb.13489/abstract

Abstract: Soil respiration (Rs) is a major pathway by which fixed carbon in the biosphere is returned to the atmosphere, yet there are limits to our ability to predict respiration rates using environmental drivers at the global scale. While temperature, moisture, carbon supply and other site characteristics are known to regulate soil respiration rates at plot scales within certain biomes, quantitative frameworks for evaluating the relative importance of these factors across different biomes and at the global scale require tests of the relationships between field estimates and global climatic data. This study evaluates the factors driving Rs at the global scale by linking global datasets of soil moisture, soil temperature, primary productivity and soil carbon estimates with observations of annual Rs from the Global Soil Respiration Database (SRDB). We find that calibrating models with parabolic soil moisture functions can improve predictive power over similar models with asymptotic functions of mean annual precipitation. Soil temperature is comparable with previously-reported air temperature observations used in predicting Rs, and is the dominant driver of Rs in global models; however, within certain biomes soil moisture or soil carbon emerge as dominant predictors of Rs. We identify regions where typical temperature-driven responses are further mediated by soil moisture, precipitation, and carbon supply and regions in which environmental controls on high Rs values are difficult to ascertain due to limited field data. Because soil moisture integrates temperature and precipitation dynamics, it can more directly constrain the heterotrophic component of Rs, but global-scale models tend to smooth its spatial heterogeneity by aggregating factors that increase moisture variability within and across biomes. We compare statistical and mechanistic models that provide independent estimates of global Rs ranging from 83 to 108 Pg/yr, but also highlight regions of uncertainty where more observations are required or environmental controls are hard to constrain.

Other papers

Methane and carbon dioxide fluxes of a temperate mire in Central Europe (Fortuniak et al. 2016) http://www.sciencedirect.com/science/article/pii/S0168192316303781

Airborne methane remote measurements reveal heavy-tail flux distribution in Four Corners region (Frankenberg et al. 2016) http://www.pnas.org/content/113/35/9734.short

Greenhouse gas emissions from natural ecosystems and agricultural lands in sub-Saharan Africa: synthesis of available data and suggestions for further research (Kim et al. 2016) http://www.biogeosciences.net/13/4789/2016/

Peak season carbon exchange shifts from a sink to a source following 50+ years of herbivore exclusion in an Arctic tundra ecosystem (Lara et al. 2016) http://onlinelibrary.wiley.com/doi/10.1111/1365-2745.12654/abstract

Vegetation carbon sequestration in Chinese forests from 2010 to 2050 (He et al. 2016) http://onlinelibrary.wiley.com/doi/10.1111/gcb.13479/abstract

CH4 concentrations over the Amazon from GOSAT consistent with in situ vertical profile data (Webb et al. 2016) http://onlinelibrary.wiley.com/doi/10.1002/2016JD025263/abstract

CH4 exchanges of the natural ecosystems in China during the past three decades: the role of wetland extent and its dynamics (Wei & Wang, 2016) http://onlinelibrary.wiley.com/doi/10.1002/2016JG003418/abstract

Mesoscale modulation of air-sea CO2 flux in Drake Passage (Song et al. 2016) http://onlinelibrary.wiley.com/doi/10.1002/2016JC011714/abstract

Biomass turnover time in terrestrial ecosystems halved by land use (Erb et al. 2016) http://www.nature.com/ngeo/journal/vaop/ncurrent/full/ngeo2782.html

Permafrost carbon as a missing link to explain CO 2 changes during the last deglaciation (Crichton et al. 2016) http://www.nature.com/ngeo/journal/vaop/ncurrent/full/ngeo2793.html

High export via small particles before the onset of the North Atlantic spring bloom (Giering et al. 2016) http://onlinelibrary.wiley.com/doi/10.1002/2016JC012048/abstract

Inorganic carbon cycling and biogeochemical processes in an Arctic inland sea (Hudson Bay) (Burt et al. 2016) http://www.biogeosciences.net/13/4659/2016/

Constrained partitioning of autotrophic and heterotrophic respiration reduces model uncertainties of forest ecosystem carbon fluxes but not stocks (Carbone et al. 2016) http://onlinelibrary.wiley.com/doi/10.1002/2016JG003386/abstract

Century-long increasing trend and variability of dissolved organic carbon export from the Mississippi River basin driven by natural and anthropogenic forcing (Ren et al. 2016) http://onlinelibrary.wiley.com/doi/10.1002/2016GB005395/abstract

Apparent winter CO2 uptake by a boreal forest due to decoupling (Jocher et al. 2016) http://www.sciencedirect.com/science/article/pii/S0168192316303495

Over-estimating climate warming-induced methane gas escape from the seafloor by neglecting multi-phase flow dynamics (Stranne et al. 2016) http://onlinelibrary.wiley.com/doi/10.1002/2016GL070049/abstract

Strong regional atmospheric 14C signature of respired CO2 observed from a tall tower over the mid-western United States (LaFranchi et al. 2016) http://onlinelibrary.wiley.com/doi/10.1002/2015JG003271/abstract

Underestimation of boreal soil carbon stocks by mathematical soil carbon models linked to soil nutrient status (Ťupek et al. 2016) http://www.biogeosciences.net/13/4439/2016/

Methane Emissions from global rice fields: Magnitude, spatio-temporal patterns and environmental controls (Zhang et al. 2016) http://onlinelibrary.wiley.com/doi/10.1002/2016GB005381/abstract

Modeling pCO2 variability in the Gulf of Mexico (Xue et al. 2016) http://www.biogeosciences.net/13/4359/2016/

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New research – extreme weather (September 7, 2016)

Posted by Ari Jokimäki on September 7, 2016

Some of the latest papers on extreme weather are shown below. First a few highlighted papers with abstracts and then a list of some other papers. If this subject interests you, be sure to check also the other papers – they are by no means less interesting than the highlighted ones.

Highlights

High-income does not protect against hurricane losses (Geiger et al. 2016) http://iopscience.iop.org/article/10.1088/1748-9326/11/8/084012/meta

Abstract: Damage due to tropical cyclones accounts for more than 50% of all meteorologically-induced economic losses worldwide. Their nominal impact is projected to increase substantially as the exposed population grows, per capita income increases, and anthropogenic climate change manifests. So far, historical losses due to tropical cyclones have been found to increase less than linearly with a nation’s affected gross domestic product (GDP). Here we show that for the United States this scaling is caused by a sub-linear increase with affected population while relative losses scale super-linearly with per capita income. The finding is robust across a multitude of empirically derived damage models that link the storm’s wind speed, exposed population, and per capita GDP to reported losses. The separation of both socio-economic predictors strongly affects the projection of potential future hurricane losses. Separating the effects of growth in population and per-capita income, per hurricane losses with respect to national GDP are projected to triple by the end of the century under unmitigated climate change, while they are estimated to decrease slightly without the separation.

A Review of Recent Advances in Research on Extreme Heat Events (Horton et al. 2016) http://rd.springer.com/article/10.1007%2Fs40641-016-0042-x

Abstract: Reviewing recent literature, we report that changes in extreme heat event characteristics such as magnitude, frequency, and duration are highly sensitive to changes in mean global-scale warming. Numerous studies have detected significant changes in the observed occurrence of extreme heat events, irrespective of how such events are defined. Further, a number of these studies have attributed present-day changes in the risk of individual heat events and the documented global-scale increase in such events to anthropogenic-driven warming. Advances in process-based studies of heat events have focused on the proximate land-atmosphere interactions through soil moisture anomalies, and changes in occurrence of the underlying atmospheric circulation associated with heat events in the midlatitudes. While evidence for a number of hypotheses remains limited, climate change nevertheless points to tail risks of possible changes in heat extremes that could exceed estimates generated from model outputs of mean temperature. We also explore risks associated with compound extreme events and nonlinear impacts associated with extreme heat.

Northern Hemisphere winter storm track trends since 1959 derived from multiple reanalysis datasets (Chang & Yau, 2016) http://link.springer.com/article/10.1007%2Fs00382-015-2911-8

Abstract: In this study, a comprehensive comparison of Northern Hemisphere winter storm track trend since 1959 derived from multiple reanalysis datasets and rawinsonde observations has been conducted. In addition, trends in terms of variance and cyclone track statistics have been compared. Previous studies, based largely on the National Center for Environmental Prediction–National Center for Atmospheric Research Reanalysis (NNR), have suggested that both the Pacific and Atlantic storm tracks have significantly intensified between the 1950s and 1990s. Comparison with trends derived from rawinsonde observations suggest that the trends derived from NNR are significantly biased high, while those from the European Center for Medium Range Weather Forecasts 40-year Reanalysis and the Japanese 55-year Reanalysis are much less biased but still too high. Those from the two twentieth century reanalysis datasets are most consistent with observations but may exhibit slight biases of opposite signs. Between 1959 and 2010, Pacific storm track activity has likely increased by 10 % or more, while Atlantic storm track activity has likely increased by <10 %. Our analysis suggests that trends in Pacific and Atlantic basin wide storm track activity prior to the 1950s derived from the two twentieth century reanalysis datasets are unlikely to be reliable due to changes in density of surface observations. Nevertheless, these datasets may provide useful information on interannual variability, especially over the Atlantic.

Landslides in a changing climate (Gariano & Guzzetti, 2016) http://www.sciencedirect.com/science/article/pii/S0012825216302458

Abstract: Warming of the Earth climate system is unequivocal. That climate changes affect the stability of natural and engineered slopes and have consequences on landslides, is also undisputable. Less clear is the type, extent, magnitude and direction of the changes in the stability conditions, and on the location, abundance, activity and frequency of landslides in response to the projected climate changes. Climate and landslides act at only partially overlapping spatial and temporal scales, complicating the evaluation of the climate impacts on landslides. We review the literature on landslide-climate studies, and find a bias in their geographical distribution, with large parts of the world not investigated. We recommend to fill the gap with new studies in Asia, South America, and Africa. We examine advantages and limits of the approaches adopted to evaluate the effects of climate variations on landslides, including prospective modelling and retrospective methods that use landslide and climate records. We consider changes in temperature, precipitation, wind and weather systems, and their direct and indirect effects on the stability of single slopes, and we use a probabilistic landslide hazard model to appraise regional landslide changes. Our review indicates that the modelling results of landslide-climate studies depend more on the emission scenarios, the Global Circulation Models, and the methods to downscale the climate variables, than on the description of the variables controlling slope processes. We advocate for constructing ensembles of projections based on a range of emissions scenarios, and to use carefully results from worst-case scenarios that may over/under-estimate landslide hazards and risk. We further advocate that uncertainties in the landslide projections must be quantified and communicated to decision makers and the public. We perform a preliminary global assessment of the future landslide impact, and we present a global map of the projected impact of climate change on landslide activity and abundance. Where global warming is expected to increase the frequency and intensity of severe rainfall events, a primary trigger of rapid-moving landslides that cause many landslide fatalities, we predict an increase in the number of people exposed to landslide risk. Finally, we give recommendations for landslide adaptation and risk reduction strategies in the framework of a warming climate.

An interdecadal shift in the number of hot nights around 1997 over Eastern China (Chen et al. 2016) http://onlinelibrary.wiley.com/doi/10.1002/asl.684/abstract

Abstract: In this study, we investigate the interdecadal variation in summer nighttime hot extremes over eastern China using observational daily minimum temperature during 1979–2013. Results show a statistically significant shift in the number of hot nights (NHN) around 1997 with averaged NHN over eastern China of 6 days more during 1997–2013 than 1979–1996. The time series of the first leading Empirical Orthogonal Function mode of the NHN is closely related with sea surface temperature anomalies over the tropical western pacific warm pool, Pacific Decadal Oscillation and Atlantic Multidecadal Oscillation, which all experienced substantial interdecadal changes in the late 1990s. Other factors such as the Urban Heat Island (UHI) effects may also contribute to the interdecadal change of the NHN around 1997.

Other papers

Intensification of landfalling typhoons over the northwest Pacific since the late 1970s (Mei & Xie, 2016) http://www.nature.com/ngeo/journal/vaop/ncurrent/full/ngeo2792.html

Increased drought and pluvial risk over California due to changing oceanic conditions (Kam & Sheffield, 2016) http://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-15-0879.1

Comparing hurricane and extratropical storm surge for the Mid-Atlantic and Northeast Coast of the United States for 1979–2013 (Booth et al. 2016) http://iopscience.iop.org/article/10.1088/1748-9326/11/9/094004/meta

Storm track processes and the opposing influences of climate change (Shaw et al. 2016) http://www.nature.com/ngeo/journal/vaop/ncurrent/full/ngeo2783.html

Can reanalysis datasets describe the persistent temperature and precipitation extremes over China? (Zhu et al. 2016) http://rd.springer.com/article/10.1007%2Fs00704-016-1912-9

Exceptionally extreme drought in Madeira Archipelago in 2012: Vegetation impacts and driving conditions (Liberato et al. 2016) http://www.sciencedirect.com/science/article/pii/S0168192316303653

An independent assessment of anthropogenic attribution statements for recent extreme temperature and rainfall events (Angélil et al. 2016) http://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-16-0077.1

Future hurricane storm surge risk for the U.S. gulf and Florida coasts based on projections of thermodynamic potential intensity (Balaguru et al. 2016) http://rd.springer.com/article/10.1007%2Fs10584-016-1728-8

Evaluation of downscaled wind speeds and parameterised gusts for recent and historical windstorms in Switzerland (Stucki et al. 2016) http://www.tellusa.net/index.php/tellusa/article/view/31820

The Record-Breaking 2015 Hurricane Season in the eastern North Pacific: An Analysis of Environmental Conditions (Collins et al. 2016) http://onlinelibrary.wiley.com/doi/10.1002/2016GL070597/abstract

Centennial drought outlook over the CONUS using NASA-NEX downscaled climate ensemble (Ahmadalipour et al. 2016) http://onlinelibrary.wiley.com/doi/10.1002/joc.4859/abstract

Compounding factors causing the unusual absence of tropical cyclones in the western North Pacific during August 2014 (Hong et al. 2016) http://onlinelibrary.wiley.com/doi/10.1002/2016JD025507/abstract

Synoptic climatology of the early 21st century drought in the Colorado River Basin and relationships to reservoir water levels (Kirk et al. 2016) http://onlinelibrary.wiley.com/doi/10.1002/joc.4855/abstract

The challenge of accurately quantifying future megadrought risk in the American Southwest (Coats & Mankin, 2016) http://onlinelibrary.wiley.com/doi/10.1002/2016GL070445/abstract

Will Global Warming Make Hurricane Forecasting More Difficult? (Emanuel, 2016) http://journals.ametsoc.org/doi/abs/10.1175/BAMS-D-16-0134.1

A comparison of heat wave climatologies and trends in China based on multiple definitions (You et al. 2016) http://link.springer.com/article/10.1007%2Fs00382-016-3315-0

Diagnosing United States hurricane landfall risk: An alternative to count-based methodologies (Staehling & Truchelut, 2016) http://onlinelibrary.wiley.com/doi/10.1002/2016GL070117/abstract

Spatial and temporal analysis of the drought vulnerability and risks over eight decades in a semi-arid region (Tensift basin: Morocco) (Fniguire et al. 2016) http://rd.springer.com/article/10.1007%2Fs00704-016-1873-z

Distinct weekly cycles of thunderstorms and a potential connection with aerosol type in China (Yang et al. 2016) http://onlinelibrary.wiley.com/doi/10.1002/2016GL070375/abstract

Trends and variability in droughts in the Pacific Islands and northeast Australia (McGree et al. 2016) http://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-16-0332.1

Spatial and temporal variations of blowing dust events in the Taklimakan Desert (Yang et al. 2016) http://rd.springer.com/article/10.1007%2Fs00704-015-1537-4

My Drought is Different from Your Drought: A Case Study of the Policy Implications of Multiple Ways of Knowing Drought (Kohl & Knox, 2016) http://journals.ametsoc.org/doi/abs/10.1175/WCAS-D-15-0062.1

Selected physical parameters as determinants of flood fatalities in Bangladesh, 1972–2013 (Paul et al. 2016) http://rd.springer.com/article/10.1007%2Fs11069-016-2384-z

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New research – temperature (September 5, 2016)

Posted by Ari Jokimäki on September 5, 2016

Some of the latest papers on temperature (in a climatic sense) are shown below. First a few highlighted papers with abstracts and then a list of some other papers. If this subject interests you, be sure to check also the other papers – they are by no means less interesting than the highlighted ones.

Highlights

Observed and simulated full-depth ocean heat-content changes for 1970–2005 (Cheng et al. 2016) http://www.ocean-sci.net/12/925/2016/

Abstract: Greenhouse-gas emissions have created a planetary energy imbalance that is primarily manifested by increasing ocean heat content (OHC). Updated observational estimates of full-depth OHC change since 1970 are presented that account for recent advancements in reducing observation errors and biases. The full-depth OHC has increased by 0.74 [0.68, 0.80]  ×  1022 J yr-1 (0.46 Wm−2) and 1.22 [1.16–1.29]  ×  1022 J yr-1 (0.75 Wm-2) for 1970–2005 and 1992–2005, respectively, with a 5 to 95 % confidence interval of the median. The CMIP5 models show large spread in OHC changes, suggesting that some models are not state-of-the-art and require further improvements. However, the ensemble median has excellent agreement with our observational estimate: 0.68 [0.54–0.82]  ×  1022 J yr-1 (0.42 Wm-2) from 1970 to 2005 and 1.25 [1.10–1.41]  ×  1022 J yr-1 (0.77 Wm-2) from 1992 to 2005. These results increase confidence in both the observational and model estimates to quantify and study changes in Earth’s energy imbalance over the historical period. We suggest that OHC be a fundamental metric for climate model validation and evaluation, especially for forced changes (decadal timescales).

Pacific sea level rise patterns and global surface temperature variability (Peyser et al. 2016) http://onlinelibrary.wiley.com/doi/10.1002/2016GL069401/abstract

Abstract: During 1998–2012, climate change and sea level rise (SLR) exhibit two notable features: a slowdown of global surface warming (hiatus) and a rapid SLR in the tropical western Pacific. To quantify their relationship, we analyze the long-term control simulations of 38 climate models. We find a significant and robust correlation between the east-west contrast of dynamic sea level (DSL) in the Pacific and global mean surface temperature (GST) variability on both interannual and decadal time scales. Based on linear regression of the multimodel ensemble mean, the anomalously fast SLR in the western tropical Pacific observed during 1998–2012 indicates suppression of a potential global surface warming of 0.16° ± 0.06°C. In contrast, the Pacific contributed 0.29° ± 0.10°C to the significant interannual GST increase in 1997/1998. The Pacific DSL anomalies observed in 2015 suggest that the strong El Niño in 2015/2016 could lead to a 0.21° ± 0.07°C GST jump.

Contrasting effects of urbanization and agriculture on surface temperature in eastern China (Zhou et al. 2016) http://onlinelibrary.wiley.com/doi/10.1002/2016JD025359/abstract

Abstract: The combined effect of urbanization and agriculture, two most pervasive land use activities, on the surface climate remains poorly understood. Using Moderate Resolution Imaging Spectroradiometer data over 2010–2015 and forests as reference, we showed that urbanization warmed the land surface temperature (LST), especially during the daytime and in growing seasons (maximized at 5.0 ± 2.0°C in May), whereas agriculture (dominated by double-cropping system) cooled the LST in two growing seasons during the daytime and all the months but July during the nighttime in Jiangsu Province, eastern China. Collectively, they had insignificant effects on the LST during the day (−0.01°C) and cooled the LST by −0.6°C at night. We also found large geographic variations associated with their thermal effects, indicated by a warming tendency southward. These spatiotemporal patterns depend strongly on vegetation activity, evapotranspiration, surface albedo, and the background climate. Our results emphasize the great potential of agriculture in offsetting the heating effects caused by rapid urbanization in China.

A summer temperature bias in early alcohol thermometers (Camuffo & Valle, 2016) http://rd.springer.com/article/10.1007%2Fs10584-016-1760-8

Abstract: This paper analyses the response of alcohol thermometers in relation to the departure from linearity and the choice of the calibration points. The result is that alcohol thermometers are affected by large departures that reach a maximum (i.e. −6 °C) at 50 °C ambient temperature. This may have caused a severe bias in early records, when alcohol thermometers were popular, especially during the Little Ice Age. Choosing a lower temperature for the upper point, calibration may substantially reduce this bias. Examples are given with thermometers in use in the 17th and 18th centuries. A careful correction of long series is necessary to avoid misleading climate interpretations.

The phenology of Arctic Ocean Surface warming (Steele & Dickinson, 2016) http://onlinelibrary.wiley.com/doi/10.1002/2016JC012089/abstract

Abstract: In this work, we explore the seasonal relationships (i.e., the phenology) between sea ice retreat, sea surface temperature (SST), and atmospheric heat fluxes in the Pacific Sector of the Arctic Ocean, using satellite and reanalysis data. We find that where ice retreats early in most years, maximum summertime SSTs are usually warmer, relative to areas with later retreat. For any particular year, we find that anomalously early ice retreat generally leads to anomalously warm SSTs. However, this relationship is weak in the Chukchi Sea, where ocean advection plays a large role. It is also weak where retreat in a particular year happens earlier than usual, but still relatively late in the season, primarily because atmospheric heat fluxes are weak at that time. This result helps to explain the very different ocean warming responses found in two recent years with extreme ice retreat, 2007 and 2012. We also find that the timing of ice retreat impacts the date of maximum SST, owing to a change in the ocean surface buoyancy and momentum forcing that occurs in early August that we term the Late Summer Transition (LST). After the LST, enhanced mixing of the upper ocean leads to cooling of the ocean surface even while atmospheric heat fluxes are still weakly downward. Our results indicate that in the near-term, earlier ice retreat is likely to cause enhanced ocean surface warming in much of the Arctic Ocean, although not where ice retreat still occurs late in the season.

Other papers

Comparisons of time series of annual mean surface air temperature for China since the 1900s: Observations, model simulations and extended reanalysis (Li et al. 2016) http://journals.ametsoc.org/doi/abs/10.1175/BAMS-D-16-0092.1

First ground-based observations of mesopause temperatures above the Eastern-Mediterranean Part I: Multi-day oscillations and tides (Silber et al. 2016) http://www.sciencedirect.com/science/article/pii/S1364682616302206

An enhanced single-channel algorithm for retrieving land surface temperature from Landsat series data (Wang et al. 2016) http://onlinelibrary.wiley.com/doi/10.1002/2016JD025270/abstract

Observed changes of temperature extremes in Serbia over the period 1961 − 2010 (Ruml et al. 2016) http://www.sciencedirect.com/science/article/pii/S016980951630254X

The inter-annual variations and the long-term trends of monthly air temperatures in Iraq over the period 1941–2013 (Muslih & Błażejczyk, 2016) http://rd.springer.com/article/10.1007%2Fs00704-016-1915-6

A multiregion model evaluation and attribution study of historical changes in the area affected by temperature and precipitation extremes (Dittus et al. 2016) http://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-16-0164.1

Changes in wind speed under heat waves enhance urban heat islands in Beijing metropolitan area (Li et al. 2016) http://journals.ametsoc.org/doi/abs/10.1175/JAMC-D-16-0102.1

Regional differential behaviour of maximum temperatures in the Iberian Peninsula regarding the Summer NAO in the second half of the twentieth century (Favà et al. 2016) http://www.sciencedirect.com/science/article/pii/S0169809516302319

Confidence intervals for time averages in the presence of long range correlations, a case study on earth surface temperature anomalies (Massah & Kantz, 2016) http://onlinelibrary.wiley.com/doi/10.1002/2016GL069555/abstract

An ensemble of ocean reanalyses for 1815–2013 with sparse observational input (Giese et al. 2016) http://onlinelibrary.wiley.com/doi/10.1002/2016JC012079/abstract

Arctic-North Pacific coupled impacts on the late autumn cold in North America (Sung et al. 2016) http://iopscience.iop.org/article/10.1088/1748-9326/11/8/084016/meta

Wet-bulb, dew point, and air temperature trends in Spain (Moratiel et al. 2016) http://rd.springer.com/article/10.1007%2Fs00704-016-1891-x

Insights into elevation-dependent warming in the Tibetan Plateau-Himalayas from CMIP5 model simulations (Palazzi et al. 2016) http://rd.springer.com/article/10.1007%2Fs00382-016-3316-z

Spatial variations in temperature in a mountainous region of Jeju Island, South Korea (Um & Kim, 2016) http://onlinelibrary.wiley.com/doi/10.1002/joc.4854/abstract

Gap filling and homogenization of climatological datasets in the headwater region of the Upper Blue Nile Basin, Ethiopia (Woldesenbet et al. 2016) http://onlinelibrary.wiley.com/doi/10.1002/joc.4839/abstract

A homogenized long-term temperature record for the Western Cape Province in South Africa: 1916–2013 (Lakhraj-Govender et al. 2016) http://onlinelibrary.wiley.com/doi/10.1002/joc.4849/abstract

Inter-model diversity of Arctic amplification caused by global warming and its relationship with the Inter-tropical Convergence Zone in CMIP5 climate models (Yim et al. 2016) http://link.springer.com/article/10.1007%2Fs00382-016-3303-4

Urban–rural differences in near-surface air temperature as resolved by the Central Europe Refined analysis (CER): sensitivity to planetary boundary layer schemes and urban canopy models (Jänicke et al. 2016) http://onlinelibrary.wiley.com/doi/10.1002/joc.4835/abstract

Monotonic Decrease of the Zonal SST Gradient of the Equatorial Pacific as a Function of CO2 Concentration in CCSM3 and CCSM4 (Yang et al. 2016) http://onlinelibrary.wiley.com/doi/10.1002/2016JD025231/abstract

Recent seasonal and long-term changes in southern Australian frost occurrence (Crimp et al. 2016) http://rd.springer.com/article/10.1007%2Fs10584-016-1763-5

Surface temperature trends from homogenized time series in South Africa: 1931–2015 (Kruger & Nxumalo, 2016) http://onlinelibrary.wiley.com/doi/10.1002/joc.4851/abstract

Investigations of the middle atmospheric thermal structure and oscillations over sub-tropical regions in the Northern and Southern Hemispheres (Sharma et al. 2016) http://rd.springer.com/article/10.1007%2Fs00382-016-3293-2

Recent amplification of the North American winter temperature dipole (Singh et al. 2016) http://onlinelibrary.wiley.com/doi/10.1002/2016JD025116/abstract

Use of remotely-sensed land surface temperature as a proxy for air temperatures at high elevations: Findings from a 5000 metre elevational transect across Kilimanjaro (Pepin et al. 2016) http://onlinelibrary.wiley.com/doi/10.1002/2016JD025497/abstract

Spatial distribution of temperature trends and extremes over Maharashtra and Karnataka States of India (Dhorde et al. 2016) http://rd.springer.com/article/10.1007%2Fs00704-016-1876-9

Assessing atmospheric temperature data sets for climate studies (Cederlöf et al. 2016) http://www.tellusa.net/index.php/tellusa/article/view/31503

Ocean heat uptake and interbasin transport of passive and redistributive surface heating (Garuba & Klinger, 2016) http://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-16-0138.1

Temperature and precipitation regional climate series over the central Pyrenees during 1910–2013 (Pérez-Zanón et al. 2016) http://onlinelibrary.wiley.com/doi/10.1002/joc.4823/abstract

Posted in Climate claims, Climate science | Leave a Comment »

New research – climate change impacts on mankind (September 2, 2016)

Posted by Ari Jokimäki on September 2, 2016

Some of the latest papers on climate change impacts on mankind are shown below. First a few highlighted papers with abstracts and then a list of some other papers. If this subject interests you, be sure to check also the other papers – they are by no means less interesting than the highlighted ones.

Highlights

Political affiliation affects adaptation to climate risks: Evidence from New York City (Botzen et al. 2016) http://rd.springer.com/article/10.1007%2Fs10584-016-1735-9

Abstract: Research reveals that liberals and conservatives in the United States diverge about their beliefs regarding climate change. We show empirically that political affiliation also matters with respect to climate related risks such as flooding from hurricanes. Our study is based on a survey conducted 6 months after Superstorm Sandy in 2012 of over 1,000 residents in flood-prone areas in New York City. Democrats’ perception of their probability of suffering flood damage is significantly higher than Republicans’ and they are also more likely to invest in individual flood protection measures. However, 50% more Democrats than Republicans in our sample expect to receive federal disaster relief after a major flood. These results highlight the importance of taking into account value-based considerations in designing disaster risk management policies.

Changes in wheat potential productivity and drought severity in Southwest China (Wang et al. 2016) http://rd.springer.com/article/10.1007%2Fs00704-016-1895-6

Abstract: Wheat production in Southwest China (SWC) plays a vital role in guaranteeing local grain security, but it is threatened by increasingly frequent seasonal drought in recent years. In spite of the importance, the impact of past climate change on wheat potential productivity and drought severity has not been properly addressed. In this study, we employed a relatively simple resource use efficiency model to analyze the spatiotemporal changes of the potential productivity (PP) and rainfed productivity (RP) of wheat (Triticum aestivum L.) in Southwest China (SWC) from 1962 to 2010. A wheat drought severity index was defined as the relative difference between PP and RP, i.e., (PP-RP)/PP, to evaluate the changing frequency and severity of drought under warming SWC. Across the entire region from 1962 to 2010, the negative impact of decreasing sunshine hours (0.06 h day−1 per decade, p < 0.05) on PP was offset by the increase in average temperature of wheat growing season (0.22 °C per decade, p < 0.01). PP increased by 283 kg ha−1 per decade (p < 0.01), while RP did not show significant trend due to increased water stress. The gap between PP and RP has increased by 26 kg ha−1 per decade (p < 0.01). Moderate and severe drought mostly occurred in central and southern SWC. The percentage of stations experienced moderate or severe drought increased by 2.0 % (p < 0.05) per decade, and reached 52 % in recent decade. Our results, together with the uneven distribution of rainfall, indicate great potential for irrigation development to harvest water and increase wheat yield under the warming climate in SWC.

Invisible water, visible impact: groundwater use and Indian agriculture under climate change (Zaveri et al. 2016) http://iopscience.iop.org/article/10.1088/1748-9326/11/8/084005/meta

Abstract: India is one of the world’s largest food producers, making the sustainability of its agricultural system of global significance. Groundwater irrigation underpins India’s agriculture, currently boosting crop production by enough to feed 170 million people. Groundwater overexploitation has led to drastic declines in groundwater levels, threatening to push this vital resource out of reach for millions of small-scale farmers who are the backbone of India’s food security. Historically, losing access to groundwater has decreased agricultural production and increased poverty. We take a multidisciplinary approach to assess climate change challenges facing India’s agricultural system, and to assess the effectiveness of large-scale water infrastructure projects designed to meet these challenges. We find that even in areas that experience climate change induced precipitation increases, expansion of irrigated agriculture will require increasing amounts of unsustainable groundwater. The large proposed national river linking project has limited capacity to alleviate groundwater stress. Thus, without intervention, poverty and food insecurity in rural India is likely to worsen.

Exploring the effect of heat on stated intentions to move (Zander et al. 2016) http://rd.springer.com/article/10.1007%2Fs10584-016-1727-9

Abstract: Climate change is leading to more frequent and longer heat waves and in many places, such as large parts of Australia, to an increase in average temperatures. Rising temperatures can reduce well-being and influence decisions about residency and mobility among people. This study assesses the intentions of a nationally representative sample of working-age people living in Australia to move to somewhere cooler than where they currently live as a response to increasing heat. We found that 11 % of respondents intend to move away from their current place or residence because of increasing temperatures. We also found that men are more likely to intend to move, as are those who feel often stressed by heat, those with a generally high level of mobility, and those who are worried about climate change. Age does not explain movement intentions although it has been found that young people are generally the most mobile, and then those in retirement age again. This means that people formerly expected to be rather immobile might be more likely to intend to move when they feel the local climate has become intolerably hot. Planning for infrastructure and service provision, which has a long lead time, will therefore need adjustment to account for the likely effects of climate change on mobility decisions and settlement patterns.

Sea ice decline and 21st century trans-Arctic shipping routes (Melia et al. 2016) http://onlinelibrary.wiley.com/doi/10.1002/2016GL069315/abstract

Abstract: The observed decline in Arctic sea ice is projected to continue, opening shorter trade routes across the Arctic Ocean, with potentially global economic implications. Here we quantify, using CMIP5 global climate model simulations calibrated to remove spatial biases, how projected sea ice loss might increase opportunities for Arctic-transit shipping. By mid-century for standard Open Water vessels, the frequency of navigable periods doubles, with routes across the central Arctic becoming available. A sea ice – ship speed relationship is used to show that European routes to Asia typically become 10 days faster via the Arctic than alternatives by mid-century, and 13 days faster by late-century, while North American routes become 4 days faster. Future greenhouse-gas emissions have a larger impact by late-century; the shipping season reaching 4-8 months in RCP8.5, double that of RCP2.6, both with substantial inter-annual variability. Moderately ice-strengthened vessels likely enable Arctic transits for 10-12 months by late-century.

Other papers

Food security or economic profitability? Projecting the effects of climate and socioeconomic changes on global skipjack tuna fisheries under three management strategies (Dueri et al. 2016) http://www.sciencedirect.com/science/article/pii/S0959378016301352

Effects of urban vegetation on mitigating exposure of vulnerable populations to excessive heat in Cleveland, Ohio (Declet-Barreto et al. 2016) http://journals.ametsoc.org/doi/abs/10.1175/WCAS-D-15-0026.1

Influence of ambient temperature and diurnal temperature range on incidence of cardiac arrhythmias (Kim & Kim, 2016) http://rd.springer.com/article/10.1007%2Fs00484-016-1221-0

Impact of weather factors on hand, foot and mouth disease, and its role in short-term incidence trend forecast in Huainan City, Anhui Province (Zhao et al. 2016) http://rd.springer.com/article/10.1007%2Fs00484-016-1225-9

Impacts of aviation fuel sulfur content on climate and human health (Kapadia et al. 2016) http://www.atmos-chem-phys.net/16/10521/2016/

Impact assessment of climate change and later-maturing cultivars on winter wheat growth and soil water deficit on the Loess Plateau of China (Ding et al. 2016) http://rd.springer.com/article/10.1007%2Fs10584-016-1714-1

Will commercial fishing be a safe occupation in future? a framework to quantify future fishing risks due to climate change scenarios (Rezaee et al. 2016) http://www.sciencedirect.com/science/article/pii/S221209471530027X

The impact of climate change on the winegrape vineyards of the Portuguese Douro region (Cunha & Richter, 2016) http://rd.springer.com/article/10.1007%2Fs10584-016-1719-9

The ‘Pacific Adaptive Capacity Analysis Framework’: guiding the assessment of adaptive capacity in Pacific island communities (Warrick et al. 2016) http://link.springer.com/article/10.1007%2Fs10113-016-1036-x

Impact of short-term temperature variability on emergency hospital admissions for schizophrenia stratified by season of birth (Zhao et al. 2016) http://rd.springer.com/article/10.1007%2Fs00484-016-1235-7

Whale watch or no watch: the Australian whale watching tourism industry and climate change (Meynecke et al. 2016) http://link.springer.com/article/10.1007%2Fs10113-016-1034-z

Perceptions of environmental change and migration decisions (Koubi et al. 2016) http://rd.springer.com/article/10.1007%2Fs10584-016-1767-1

An overview of the opportunities and challenges of promoting climate change adaptation at the local level: a case study from a community adaptation planning in Nepal (Regmi et al. 2016) http://rd.springer.com/article/10.1007%2Fs10584-016-1765-3

Heat exposure on farmers in northeast Ghana (Frimpong et al. 2016) http://rd.springer.com/article/10.1007%2Fs00484-016-1219-7

The effect of future ambient air pollution on human premature mortality to 2100 using output from the ACCMIP model ensemble (Silva et al. 2016) http://www.atmos-chem-phys.net/16/9847/2016/

Assessment of atmospheric moisture harvesting by direct cooling (Gido et al. 2016) http://www.sciencedirect.com/science/article/pii/S0169809516302216

Demand for biodiversity protection and carbon storage as drivers of global land change scenarios (Eitelberg et al. 2016) http://www.sciencedirect.com/science/article/pii/S0959378016300978

Adaptation to Climate Change: Commitment and Timing Issues (Breton & Sbragia, 2016) http://rd.springer.com/article/10.1007%2Fs10640-016-0056-9

Markets and climate are driving rapid change in farming practices in Savannah West Africa (Ouédraogo et al. 2016) http://rd.springer.com/article/10.1007%2Fs10113-016-1029-9

Farmer-level adaptation to climate change and agricultural drought: empirical evidences from the Barind region of Bangladesh (Hossain et al. 2016) http://rd.springer.com/article/10.1007%2Fs11069-016-2360-7

Climatic consequences of adopting drought tolerant vegetation over Los Angeles as a response to California drought (Vahmani & Ban-Weiss, 2016) http://onlinelibrary.wiley.com/doi/10.1002/2016GL069658/abstract

Increased climate risk in Brazilian double cropping agriculture systems: Implications for land use in Northern Brazil (Pires et al. 2016) http://www.sciencedirect.com/science/article/pii/S0168192316303318

The influence of the winter North Atlantic Oscillation index on hospital admissions through diseases of the circulatory system in Lisbon, Portugal (Almendra et al. 2016) http://rd.springer.com/article/10.1007%2Fs00484-016-1214-z

Posted in Adaptation & Mitigation, Global warming effects | Leave a Comment »

New research – climate change mitigation (September 1, 2016)

Posted by Ari Jokimäki on September 1, 2016

Some of the latest papers on climate change mitigation are shown below. First a few highlighted papers with abstracts and then a list of some other papers. If this subject interests you, be sure to check also the other papers – they are by no means less interesting than the highlighted ones.

Highlights

Climate change and individual duties (Fragnière, 2016) http://onlinelibrary.wiley.com/doi/10.1002/wcc.422/abstract

Abstract: Tackling climate change has often been considered the responsibility of national governments. But do individuals also have a duty to act in the face of this problem? In particular, do they have a duty to adopt a greener lifestyle or to press their government to act? This review critically examines the arguments provided for and against such duties in the relevant philosophic literature. It first discusses the problem of causal inefficacy—namely the fact that individual greenhouse gas emissions appear to make no difference to the harmful consequences of climate change—and whether it clears individuals from any moral obligations related to climate change. Then, it considers various other arguments for the existence of such duties, including integrity, fairness, universalizability, or virtue. Finally, it assesses the existence of a duty to promote collective action through active citizenship. The conclusion emphasizes that most writers agree on the fact that individuals have at least some duties to take action against climate change, but that disagreement remains about the exact nature and, above all, the extent of these duties.

Renewable and nuclear electricity: Comparison of environmental impacts (McCombie & Jefferson, 2016) http://www.sciencedirect.com/science/article/pii/S0301421516301240

Abstract: Given the widely acknowledged negative impacts of fossil fuels, both on human health and on potential climate change, it is of interest to compare the impacts of low carbon alternative energy sources such as nuclear energy, hydropower, solar, wind and biomass. In this paper, we review the literature in order to summarise the impacts of the different technologies in terms of their materials and energy requirements, their emissions during operation, their health effects during operation, the accident risks, and the associated waste streams. We follow up these comparisons with some more anecdotal evidence on selected impacts that are either particularly topical or are important but less commonly addressed. These include impacts of wind turbines on persons and on bird life, the underestimated problems with biomass, and concerns about biodiversity reduction. Finally we address the public attitudes towards both renewable energy technologies and to nuclear power. The conclusion is drawn that energy policies of many countries are perhaps more strongly influenced by public and political perceptions of available technologies than they are by rational assessment of the actual benefits and drawbacks. Policy recommendations follow from this conclusion.

Consideration of Land Use Change-Induced Surface Albedo Effects in Life-Cycle Analysis of Biofuels (Cai et al. 2016) http://pubs.rsc.org/en/Content/ArticleLanding/2016/EE/C6EE01728B

Abstract: Land use change (LUC)-induced surface albedo effects for expansive biofuel production need to be quantified for improved understanding of biofuel climate impacts. We addressed this emerging issue for expansive biofuel production in the United States (U.S.) and compared the albedo effects with greenhouse gas emissions highlighted by traditional life-cycle analysis of biofuels. We used improved spatial representation of albedo effects in our analysis by obtaining over 1.4 million albedo observations from the Moderate Resolution Imaging Spectroradiometer flown on NASA satellites over a thousand counties representative of six Agro-Ecological Zones (AEZs) in the U.S. We utilized high-spatial-resolution, crop-specific cropland cover data from the U.S. Department of Agriculture and paired the data with the albedo data to enable consideration of various LUC scenarios. We simulated the radiative effects of LUC-induced albedo changes for seven types of crop covers using the Monte Carlo Aerosol, Cloud and Radiation model, which employs an advanced radiative transfer mechanism coupled with spatially and temporally resolved meteorological and aerosol conditions. These simulations estimated the net radiative fluxes at the top of the atmosphere as a result of the LUC-induced albedo changes, which enabled quantification of the albedo effects on the basis of radiative forcing defined by the Intergovernmental Panel on Climate Change for CO2 and other greenhouse gases effects. Finally, we quantified the LUC-induced albedo effects for production of ethanol from corn, miscanthus, and switchgrass in different AEZs of the U.S. Results show that the weighted national average albedo effect is a small cooling effect of −1.8 g CO2 equivalent (CO2e) for a mega-Joule (MJ) of corn ethanol, a relatively stronger warming effect of 12.1 g CO2e per MJ of switchgrass ethanol, and a small warming effect of 2.7 g CO2e per MJ of miscanthus ethanol. Significant variations in albedo-induced effects are found among different land conversions for the same biofuel, and among different AEZ regions for the same land conversion and biofuel. This spatial heterogeneity, owing to non-linear albedo dynamics and radiation processes, suggests highly variable LUC-induced albedo effects depending on geographical locations and vegetation. These findings provide new insights on potential climate effects by producing biofuels through considering biogeophysical as well as biogeochemical effects of biofuel production and use in the U.S.

Quantifying expert consensus against the existence of a secret, large-scale atmospheric spraying program (Shearer et al. 2016) http://iopscience.iop.org/article/10.1088/1748-9326/11/8/084011/meta

Abstract: Nearly 17% of people in an international survey said they believed the existence of a secret large-scale atmospheric program (SLAP) to be true or partly true. SLAP is commonly referred to as ‘chemtrails’ or ‘covert geoengineering’, and has led to a number of websites purported to show evidence of widespread chemical spraying linked to negative impacts on human health and the environment. To address these claims, we surveyed two groups of experts—atmospheric chemists with expertize in condensation trails and geochemists working on atmospheric deposition of dust and pollution—to scientifically evaluate for the first time the claims of SLAP theorists. Results show that 76 of the 77 scientists (98.7%) that took part in this study said they had not encountered evidence of a SLAP, and that the data cited as evidence could be explained through other factors, including well-understood physics and chemistry associated with aircraft contrails and atmospheric aerosols. Our goal is not to sway those already convinced that there is a secret, large-scale spraying program—who often reject counter-evidence as further proof of their theories—but rather to establish a source of objective science that can inform public discourse.

The Conditional Nature of the Local Warming Effect (Druckman & Shafranek, 2016) http://journals.ametsoc.org/doi/abs/10.1175/WCAS-D-16-0012.1

Abstract: The local warming effect occurs when perceived deviations in the day’s temperature affect individuals’ global warming beliefs. When people perceive the day to be warmer than usual, they tend to overestimate the number of warm days throughout the year, and to report increased belief in and worry about global warming. For many, this is normatively concerning because a single day’s perceived temperature fluctuation is not representative of longer-term, large-scale climate patterns. It thus makes for a poor basis for global warming judgments. Recent work shows that the local warming effect might disappear when people receive a reminder to think about weather patterns over the past year (i.e., a correction). This paper employs a survey experiment that extends past research by exploring the generalizability, conditionality, and durability of the corrective information. It identifies the conditions under which a local warming effect is more or less likely to occur.

Other papers

The importance of climate change and nitrogen use efficiency for future nitrous oxide emissions from agriculture (Kanter et al. 2016) http://iopscience.iop.org/article/10.1088/1748-9326/11/9/094003/meta

Methane emissions measurements of natural gas components using a utility terrain vehicle and portable methane quantification system (Johnson & Heltzel, 2016) http://www.sciencedirect.com/science/article/pii/S1352231016306586

Impacts of current and projected oil palm plantation expansion on air quality over Southeast Asia (Silva et al. 2016) http://www.atmos-chem-phys.net/16/10621/2016/

Climate change education and knowledge among Nigerian university graduates (Ayanlade & Jegede, 2016) http://journals.ametsoc.org/doi/abs/10.1175/WCAS-D-15-0071.1

Potential emission savings from refrigeration and air conditioning systems by using low GWP refrigerants (Beshr et al. 2016) http://rd.springer.com/article/10.1007%2Fs11367-016-1186-6

The world’s biggest gamble (Rockström et al. 2016) http://onlinelibrary.wiley.com/doi/10.1002/2016EF000392/abstract

Statements about climate researchers’ carbon footprints affect their credibility and the impact of their advice (Attari et al. 2016) http://rd.springer.com/article/10.1007%2Fs10584-016-1713-2

Should environmentalists be concerned about materialism? An analysis of attitudes, behaviours and greenhouse gas emissions (Andersson & Nässén, 2016) http://www.sciencedirect.com/science/article/pii/S0272494416300767

Austria’s wind energy potential – A participatory modeling approach to assess socio-political and market acceptance (Höltinger et al. 2016) http://www.sciencedirect.com/science/article/pii/S0301421516304268

Time-varying analysis of CO2 emissions, energy consumption, and economic growth nexus: Statistical experience in next 11 countries (Shahbaz et al. 2016) http://www.sciencedirect.com/science/article/pii/S030142151630427X

China’s wind electricity and cost of carbon mitigation are more expensive than anticipated (Lam et al. 2016) http://iopscience.iop.org/article/10.1088/1748-9326/11/8/084015/meta

New Tools for Comparing Beliefs about the Timing of Recurrent Events with Climate Time Series Datasets (Stiller-Reeve et al. 2016) http://journals.ametsoc.org/doi/abs/10.1175/WCAS-D-15-0054.1

Most Americans Want to Learn More about Climate Change (Perkins et al. 2016) http://journals.ametsoc.org/doi/abs/10.1175/BAMS-D-16-0097.1

Atmosfear: Communicating the Effects of Climate Change on Extreme Weather (Janković & Schultz, 2016) http://journals.ametsoc.org/doi/abs/10.1175/WCAS-D-16-0030.1

Rapid scale-up of negative emissions technologies: social barriers and social implications (Buck, 2016) http://rd.springer.com/article/10.1007%2Fs10584-016-1770-6

Revisiting the climate impacts of cool roofs around the globe using an Earth system model (Zhang et al. 2016) http://iopscience.iop.org/article/10.1088/1748-9326/11/8/084014/meta

Low carbon cities: is ambitious action affordable? (Sudmant et al. 2016) http://rd.springer.com/article/10.1007%2Fs10584-016-1751-9

Energy efficiency outlook in China’s urban buildings sector through 2030 (McNeil et al. 2016) http://www.sciencedirect.com/science/article/pii/S0301421516303949

Wind, hydro or mixed renewable energy source: Preference for electricity products when the share of renewable energy increases (Yang et al. 2016) http://www.sciencedirect.com/science/article/pii/S0301421516303913

Reducing beef consumption might not reduce emissions: response to Phalan et al. (2016) (Barioni et al. 2016) http://onlinelibrary.wiley.com/doi/10.1111/gcb.13458/abstract

Universal access to electricity in Burkina Faso: scaling-up renewable energy technologies (Moner-Girona et al. 2016) http://iopscience.iop.org/article/10.1088/1748-9326/11/8/084010/meta

A New Model for the Lifetime of Fossil Fuel Resources (Michaelides, 2016) http://rd.springer.com/article/10.1007%2Fs11053-016-9307-2

A method to estimate climate-critical construction materials applied to seaport protection (Becker et al. 2016) http://www.sciencedirect.com/science/article/pii/S0959378016301261

Multi-model assessment of global hydropower and cooling water discharge potential under climate change (van Vliet et al. 2016) http://www.sciencedirect.com/science/article/pii/S0959378016301236

Technoeconomic assessment of beetle kill biomass co-firing in existing coal fired power plants in the Western United States (Beagle & Belmont, 2016) http://www.sciencedirect.com/science/article/pii/S0301421516304141

Statistical analysis of compliance violations for natural gas wells in Pennsylvania (Abualfaraj et al. 2016) http://www.sciencedirect.com/science/article/pii/S0301421516304128

A new way of carbon accounting emphasises the crucial role of sustainable timber use for successful carbon mitigation strategies (Härtl et al. 2016) http://link.springer.com/article/10.1007%2Fs11027-016-9720-1

Climate consequences of low-carbon fuels: The United States Renewable Fuel Standard (Hill et al. 2016) http://www.sciencedirect.com/science/article/pii/S0301421516303962

A spatially explicit assessment of the wind energy potential in response to an increased distance between wind turbines and settlements in Germany (Masurowski et al. 2016) http://www.sciencedirect.com/science/article/pii/S0301421516303718

The scientific veneer of IPCC visuals (McMahon et al. 2016) http://rd.springer.com/article/10.1007%2Fs10584-016-1758-2

Climate impacts of geoengineering in a delayed mitigation scenario (Tilmes et al. 2016) http://onlinelibrary.wiley.com/doi/10.1002/2016GL070122/abstract

Co-benefits of global and regional greenhouse gas mitigation for US air quality in 2050 (Zhang et al. 2016) http://www.atmos-chem-phys.net/16/9533/2016/

Increasing recycling through displaying feedback and social comparative feedback (Mickaël & Sébastien, 2016) http://www.sciencedirect.com/science/article/pii/S0272494416300652

How geographic distance and political ideology interact to influence public perception of unconventional oil/natural gas development (Clarke et al. 2016) http://www.sciencedirect.com/science/article/pii/S0301421516303925

Assessing greenhouse gas emissions of milk production: which parameters are essential? (Wolf et al. 2016) http://rd.springer.com/article/10.1007%2Fs11367-016-1165-y

Do effects of theoretical training and rewards for energy-efficient behavior persist over time and interact? A natural field experiment on eco-driving in a company fleet (Schall et al. 2016) http://www.sciencedirect.com/science/article/pii/S0301421516303603

Evaluation of usage and fuel savings of solar ovens in Nicaragua (Bauer, 2016) http://www.sciencedirect.com/science/article/pii/S0301421516304025

Transport demand, harmful emissions, environment and health co-benefits in China (He & Qiu, 2016) http://www.sciencedirect.com/science/article/pii/S0301421516304001

Key challenges to expanding renewable energy (Stram, 2016) http://www.sciencedirect.com/science/article/pii/S0301421516302646

Economics of nuclear and renewables (Khatib & Difiglio, 2016) http://www.sciencedirect.com/science/article/pii/S030142151630180X

Nuclear power: Status report and future prospects (Budnitz, 2016) http://www.sciencedirect.com/science/article/pii/S0301421516301124

Afforestation to mitigate climate change: impacts on food prices under consideration of albedo effects (Kreidenweis et al. 2016) http://iopscience.iop.org/article/10.1088/1748-9326/11/8/085001/meta

Supplementing Domestic Mitigation and Adaptation with Emissions Reduction Abroad to Face Climate Change (Ayong Le Kama & Pommeret, 2016) http://link.springer.com/article/10.1007%2Fs10640-016-0050-2

Re-framing the climate change debate in the livestock sector: mitigation and adaptation options (Rivera-Ferre et al. 2016) http://onlinelibrary.wiley.com/doi/10.1002/wcc.421/abstract

Readily implementable techniques can cut annual CO2 emissions from the production of concrete by over 20% (Miller, Horvath & Monteiro, 2016) http://iopscience.iop.org/article/10.1088/1748-9326/11/7/074029/meta

Risk, Liability, and Economic Issues with Long-Term CO2 Storage—A Review (Anderson, 2016) http://rd.springer.com/article/10.1007%2Fs11053-016-9303-6

Global low-carbon transition and China’s response strategies (He, 2016) http://www.sciencedirect.com/science/article/pii/S1674927816300223

Realizing potential savings of energy and emissions from efficient household appliances in India (Parikh & Parikh, 2016) http://www.sciencedirect.com/science/article/pii/S0301421516303585

Coal power overcapacity and investment bubble in China during 2015–2020 (Yuan et al. 2016) http://www.sciencedirect.com/science/article/pii/S0301421516303615

Posted in Adaptation & Mitigation | Leave a Comment »

New research – climate change impacts on cryosphere (August 31, 2016)

Posted by Ari Jokimäki on August 31, 2016

Some of the latest papers on climate change impacts on cryosphere are shown below. First a few highlighted papers with abstracts and then a list of some other papers. If this subject interests you, be sure to check also the other papers – they are by no means less interesting than the highlighted ones.

Highlights

Rapid glacial retreat on the Kamchatka Peninsula during the early 21st century (Lynch et al. 2016) http://www.the-cryosphere.net/10/1809/2016/

Abstract: Monitoring glacier fluctuations provides insights into changing glacial environments and recent climate change. The availability of satellite imagery offers the opportunity to view these changes for remote and inaccessible regions. Gaining an understanding of the ongoing changes in such regions is vital if a complete picture of glacial fluctuations globally is to be established. Here, satellite imagery (Landsat 7, 8 and ASTER) is used to conduct a multi-annual remote sensing survey of glacier fluctuations on the Kamchatka Peninsula (eastern Russia) over the 2000–2014 period. Glacier margins were digitised manually and reveal that, in 2000, the peninsula was occupied by 673 glaciers, with a total glacier surface area of 775.7 ± 27.9 km2. By 2014, the number of glaciers had increased to 738 (reflecting the fragmentation of larger glaciers), but their surface area had decreased to 592.9 ± 20.4 km2. This represents a  ∼  24 % decline in total glacier surface area between 2000 and 2014 and a notable acceleration in the rate of area loss since the late 20th century. Analysis of possible controls indicates that these glacier fluctuations were likely governed by variations in climate (particularly rising summer temperatures), though the response of individual glaciers was modulated by other (non-climatic) factors, principally glacier size, local shading and debris cover.

How predictable is the timing of a summer ice-free Arctic? (Jahn et al. 2016) http://onlinelibrary.wiley.com/doi/10.1002/2016GL070067/abstract

Abstract: Climate Model simulations give a large range of over 100 years for predictions of when the Arctic could first become ice-free in the summer, and many studies have attempted to narrow this uncertainty range. However, given the chaotic nature of the climate system, what amount of spread in the prediction of an ice-free summer Arctic is inevitable? Based on results from large ensemble simulations with the Community Earth System Model, we show that internal variability alone leads to a prediction uncertainty of about two decades, while scenario uncertainty between the strong (RCP8.5) and medium (RCP4.5) forcing scenarios adds at least another 5 years. Common metrics of the past and present mean sea ice state (such as ice extent, volume, and thickness) as well as global mean temperatures do not allow a reduction of the prediction uncertainty from internal variability.

Satellite observed changes in the Northern Hemisphere snow cover phenology and the associated radiative forcing and feedback between 1982 and 2013 (Chen et al. 2016) http://iopscience.iop.org/article/10.1088/1748-9326/11/8/084002/meta

Abstract: Quantifying continental-scale changes in snow cover phenology (SCP) and evaluating their associated radiative forcing and feedback is essential for meteorological, hydrological, ecological, and societal purposes. However, the current SCP research is inadequate because few published studies have explored the long-term changes in SCP, as well as their associated radiative forcing and feedback in the context of global warming. Based on satellite-observed snow cover extent (SCE) and land surface albedo datasets, and using a radiative kernel modeling method, this study quantified changes in SCP and the associated radiative forcing and feedback over the Northern Hemisphere (NH) snow-covered landmass from 1982 to 2013. The monthly SCE anomaly over the NH displayed a significant decreasing trend from May to August (−0.89 × 106 km2 decade−1), while an increasing trend from November to February (0.65 × 106 km2 decade−1) over that period. The changes in SCE resulted in corresponding anomalies in SCP. The snow onset date (Do) moved forward slightly, but the snow end date (De) advanced significantly at the rate of 1.91 days decade−1, with a 73% contribution from decreased SCE in Eurasia (EU). The anomalies in De resulted in a weakened snow radiative forcing of 0.12 (±0.003) W m−2 and feedback of 0.21 (±0.005) W m−2 K−1, in melting season, over the NH, from 1982 to 2013. Compared with the SCP changes in EU, the SCP anomalies in North America were relatively stable because of the clearly contrasting De anomalies between the mid- and high latitudes in this region.

Grounding Line Variability and Subglacial Lake Drainage on Pine Island Glacier, Antarctica (Joughin et al. 2016) http://onlinelibrary.wiley.com/doi/10.1002/2016GL070259/abstract

Abstract: We produced a 6-year time series of differential tidal displacement for Pine Island Ice Shelf, Antarctica, using speckle-tracking methods applied to fine-resolution TerraSAR-X data. These results reveal that the main grounding line has maintained a relatively steady position over the last 6 years, following the speedup that terminated in ~2009. In the middle of the shelf, there are grounded spots that migrate downstream over the 6-year record. Examination of high-resolution DEMs reveals that these grounded spots form where deep keels (thickness anomalies) advect over an approximately flow-parallel bathymetric high, maintaining intermittent contact with the bed. These datasets also reveal several subsidence and uplift events associated with subglacial lake drainages in the fast-flowing region above the grounding line. Although these drainages approximately double the rate of subglacial water flow over periods of a few weeks, they have no discernible effect on horizontal flow speed.

Influences of surface air temperature and atmospheric circulation on winter snow cover variability over Europe (Ye & Lau, 2016) http://onlinelibrary.wiley.com/doi/10.1002/joc.4868/abstract

Abstract: The relationships between snow cover (SC) variability in Europe, the local surface air temperature (SAT), and the associated atmospheric circulation changes are studied. This investigation indicates that the European winter SC is closely correlated with SAT. Higher (lower) SC is coincident with strong and large-scale surface cooling (warming). Similar but weaker temperature signals are observed in the middle and upper troposphere. Periods of enhanced (reduced) SC are characterized by surface heat loss (gain), partly due to dampened (enhanced) sensible heat fluxes towards the ground surface, which is in turn related to the lower (higher) SAT. Higher (lower) SC is also accompanied by reduced (enhanced) downward longwave irradiance. Consistent with previous studies, our analysis demonstrates that variations in the atmospheric circulation in the North Atlantic/European sector, including those associated with the North Atlantic Oscillation, are accompanied by changes in horizontal heat advection and SC over Europe. The circulation changes modulate the water vapour transport towards the European continent, and thereby influence the available water vapour there and lead to fluctuations in downward longwave irradiance and cloud cover. The wind anomalies associated with these variations also drive surface heat flux changes in the North Atlantic, which in turn lead to well-defined sea surface temperature (SST) tendencies. The above characteristic patterns exhibit notable variability in different calendar months of the winter season. The monthly averaged circulation anomalies are evidently related to changes in the tracks of atmospheric disturbances with synoptic time scales. Overall, there is no strong evidence supporting a principal role for the North Atlantic SST or the El Niño Southern Oscillation in driving inter-annual SC variability over Europe.

Other papers

Anthropogenic impact on Antarctic surface mass balance, currently masked by natural variability, to emerge by mid-century (Previdi & Polvani, 2016) http://iopscience.iop.org/article/10.1088/1748-9326/11/9/094001/meta

Reduced melt on debris-covered glaciers: investigations from Changri Nup Glacier, Nepal (Vincent et al. 2016) http://www.the-cryosphere.net/10/1845/2016/

Increasing water vapor transport to the Greenland Ice Sheet revealed using self-organizing maps (Mattingly et al. 2016) http://onlinelibrary.wiley.com/doi/10.1002/2016GL070424/abstract

Fine-scale spatial variation in ice cover and surface temperature trends across the surface of the Laurentian Great Lakes (Mason et al. 2016) http://rd.springer.com/article/10.1007%2Fs10584-016-1721-2

On the feedback of the winter NAO-driven sea ice anomalies (García-Serrano & Frankignoul, 2016) http://link.springer.com/article/10.1007%2Fs00382-015-2922-5

Estimation of melt pond fraction over high-concentration Arctic sea ice using AMSR-E passive microwave data (Tanaka et al. 2016) http://onlinelibrary.wiley.com/doi/10.1002/2016JC011876/abstract

A simple equation for the melt elevation feedback of ice sheets (Levermann & Winkelmann, 2016) http://www.the-cryosphere.net/10/1799/2016/

Hail climatology and trends in Romania: 1961-2014 (Burcea et al. 2016) http://journals.ametsoc.org/doi/abs/10.1175/MWR-D-16-0126.1

Influence of the Eurasian snow on the negative North Atlantic Oscillation in subseasonal forecasts of the cold winter 2009/2010 (Orsolini et al. 2016) http://rd.springer.com/article/10.1007%2Fs00382-015-2903-8

Annual Greenland accumulation rates (2009–2012) from airborne snow radar (Koenig et al. 2016) http://www.the-cryosphere.net/10/1739/2016/

Ice-margin and meltwater dynamics during the mid-Holocene in the Kangerlussuaq area of west Greenland (Carrivick et al. 2016) http://onlinelibrary.wiley.com/doi/10.1111/bor.12199/abstract

The robustness of mid-latitude weather pattern changes due to Arctic sea-ice loss (Chen et al. 2016) http://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-16-0167.1

Arctic Sea Ice Seasonal Prediction by a Linear Markov Model (Yuan et al. 2016) http://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-15-0858.1

Testing the recent snow drought as an analog for climate warming sensitivity of Cascades snowpacks (Cooper et al. 2016) http://iopscience.iop.org/article/10.1088/1748-9326/11/8/084009/meta

Summer Atmospheric Circulation Anomalies over the Arctic Ocean and Their Influences on September Sea Ice Extent: A Cautionary Tale (Serreze et al. 2016) http://onlinelibrary.wiley.com/doi/10.1002/2016JD025161/abstract

The abandoned ice sheet base at Camp Century, Greenland, in a warming climate (Colgan et al. 2016) http://onlinelibrary.wiley.com/doi/10.1002/2016GL069688/abstract

Thermal impacts of engineering activities and vegetation layer on permafrost in different alpine ecosystems of the Qinghai–Tibet Plateau, China (Wu et al. 2016) http://www.the-cryosphere.net/10/1695/2016/

Greenland annual accumulation along the EGIG line, 1959–2004, from ASIRAS airborne radar and neutron-probe density measurements (Overly et al. 2016)
http://www.the-cryosphere.net/10/1679/2016/

Attribution of spring snow water equivalent (SWE) changes over the northern hemisphere to anthropogenic effects (Jeong et al. 2016)
http://rd.springer.com/article/10.1007%2Fs00382-016-3291-4

Historical analysis and visualization of the retreat of Findelengletscher, Switzerland, 1859-2010 (Rastner et al. 2016)
http://www.sciencedirect.com/science/article/pii/S0921818116300698

Observed spatio-temporal changes of winter snow albedo over the north-west Himalaya (Negi et al. 2016)
http://onlinelibrary.wiley.com/doi/10.1002/joc.4846/abstract

An evaluation of high-resolution regional climate model simulations of snow cover and albedo over the Rocky Mountains, with implications for the simulated snow-albedo feedback (Minder et al. 2016)
http://onlinelibrary.wiley.com/doi/10.1002/2016JD024995/abstract

Statistical indicators of Arctic sea-ice stability – prospects and limitations (Bathiany et al. 2016)
http://www.the-cryosphere.net/10/1631/2016/

Effects of stratified active layers on high-altitude permafrost warming: a case study on the Qinghai–Tibet Plateau (Pan et al. 2016)
http://www.the-cryosphere.net/10/1591/2016/

Posted in Climate science, Global warming effects | Leave a Comment »

 
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