New research from last week 46/2012
Posted by Ari Jokimäki on November 19, 2012
This was somewhat quiet week for climate science. You can also see it from papers below – there are quite a few papers that are from related fields of science. However, I think this is just natural variability and not indicative of some long-term changes in publication activity in climate science. I received 364 papers to my RSS feed reader this week. Below I have included 12 (in the main section) + 26 (in other studies section) = 38, which is 10.4 % of new papers I saw last week. Not bad percentage, I think.
Let’s take some open access news. Royal Society Publishing: “All our content is free to access until 29 November 2012” (if you are interested in science history, you could have some fun visiting their journals, some of which started publishing hundreds of years ago). Also, Springer: “View for free on the new SpringerLink through November 30,2012” for Climatic Change, Climate Dynamics, and Theoretical and Applied Climatology (and for some other journals as well).
North Atlantic tropical cyclone intensity is projected to increase
Abstract: “Tropical cyclones – particularly intense ones – are a hazard to life and property, so an assessment of the changes in North Atlantic tropical cyclone intensity has important socio-economic implications. In this study we focus on the seasonally integrated Power Dissipation Index (PDI) as a metric to project changes in tropical cyclone intensity. Based on a recently developed statistical model, we examine projections in North Atlantic PDI using output from 17 state-of-the-art global climate models and three radiative forcing scenarios. Overall, we find that North Atlantic PDI is projected to increase with respect to the 1986-2005 period across all scenarios. The difference between the PDI projections and those of the number of North Atlantic tropical cyclones, which are not projected to increase significantly, indicates an intensification of North Atlantic tropical cyclones in response to both greenhouse gas (GHG) increases and aerosol changes over the current century. At the end of the 21st century, the magnitude of these increases shows a positive dependence on projected GHG forcing. The projected intensification is significantly enhanced by non-GHG (primarily aerosol) forcing in the first half of the 21st century.”
Citation: Gabriele Villarini and Gabriel A. Vecchi, Journal of Climate 2012, doi: http://dx.doi.org/10.1175/JCLI-D-12-00441.1.
Extreme precipitation events have become more common in Europe
Abstract: “Significant trends in precipitation extremes over Europe since the middle of the 20th century have been found in earlier studies. Most of these studies are based on descriptive indices of moderate extremes that occur on average a few times per year. Here we have analyzed rarer precipitation events which occur on average once in 5, 10 and 20 years in the 1950s and 1960s using extreme value theory. We have focused on the 1-d and 5-d precipitation amounts in Northern and Southern Europe in all four seasons. Changes over the time period 1951–2010 are studied by considering five consecutive 20-year time intervals with 10-year overlap. Despite considerable decadal variability, our results indicate that 5-, 10- and 20-year events of 1-d and 5-d precipitation for the first 20-year period generally became more common during this 60-year period. For all regions, seasons and return periods, the median reduction in return period between the first and last 20-year periods is ∼21% with variations between a decrease of ∼2% and ∼58%.”
Citation: E. J. M. van den Besselaar, A. M. G. Klein Tank, T. A. Buishand, International Journal of Climatology, DOI: 10.1002/joc.3619.
The global energy balance from a surface perspective
Abstract: “In the framework of the global energy balance, the radiative energy exchanges between Sun, Earth and space are now accurately quantified from new satellite missions. Much less is known about the magnitude of the energy flows within the climate system and at the Earth surface, which cannot be directly measured by satellites. In addition to satellite observations, here we make extensive use of the growing number of surface observations to constrain the global energy balance not only from space, but also from the surface. We combine these observations with the latest modeling efforts performed for the 5th IPCC assessment report to infer best estimates for the global mean surface radiative components. Our analyses favor global mean downward surface solar and thermal radiation values near 185 and 342 Wm−2, respectively, which are most compatible with surface observations. Combined with an estimated surface absorbed solar radiation and thermal emission of 161 and 397 Wm−2, respectively, this leaves 106 Wm−2 of surface net radiation available globally for distribution amongst the non-radiative surface energy balance components. The climate models overestimate the downward solar and underestimate the downward thermal radiation, thereby simulating nevertheless an adequate global mean surface net radiation by error compensation. This also suggests that, globally, the simulated surface sensible and latent heat fluxes, around 20 and 85 Wm−2 on average, state realistic values. The findings of this study are compiled into a new global energy balance diagram, which may be able to reconcile currently disputed inconsistencies between energy and water cycle estimates.”
Citation: Martin Wild, Doris Folini, Christoph Schär, Norman Loeb, Ellsworth G. Dutton, Gert König-Langlo, Climate Dynamics, November 2012, DOI: 10.1007/s00382-012-1569-8.
New Arctic sea ice extent time series from the 1950s to present
Abstract: “Observations from passive microwave satellite sensors have provided a continuous and consistent record of sea ice extent since late 1978. Earlier records, compiled from ice charts and other sources exist, but are not consistent with the satellite record. Here, a method is presented to adjust a compilation of pre-satellite sources to remove discontinuities between the two periods and create a more consistent combined 59-yr time series spanning 1953–2011. This adjusted combined time series shows more realistic behavior across the transition between the two individual time series and thus provides higher confidence in trend estimates from 1953 through 2011. The long-term time series is used to calculate linear trend estimates and compare them with trend estimates from the satellite period. The results indicate that trends through the 1960s were largely positive (though not statistically significant) and then turned negative by the mid-1970s and have been consistently negative since, reaching statistical significance (at the 95% confidence level) by the late 1980s. The trend for September (when Arctic extent reaches its seasonal minimum) for the satellite period, 1979–2011 is −12.9% decade−1, nearly double the 1953–2011 trend of−6.8% decade−1 (percent relative to the 1981–2010 mean). The recent decade (2002–2011) stands out as a period of persistent decline in ice extent. The combined 59-yr time series puts the strong observed decline in the Arctic sea ice cover during 1979–2011 in a longer-term context and provides a useful resource for comparisons with historical model estimates.”
Citation: Meier, W. N., Stroeve, J., Barrett, A., and Fetterer, F.: A simple approach to providing a more consistent Arctic sea ice extent time series from the 1950s to present, The Cryosphere, 6, 1359-1368, doi:10.5194/tc-6-1359-2012, 2012.
Air pollution around Paris seems to increase lightning activity
Highlights: ► First time lightning data used in France to investigate anthropogenic influence ► General lightning production more intense on Tuesday, Wednesday, and Thursday ► Lightning activity indicative of convection enhanced over Paris (UHI influence) ► Lightning favoured downwind of Paris on Tuesday and Thursday (most worked days) ► High percentage of + CG downwind of Paris during weekend.
Abstract: “12 summers of cloud-to-ground (CG) lightning flashes data over a 200 km × 200 km domain centred on Paris (France) have been analyzed to infer the possible influence of pollution on lightning activity. Lightning flashes densities are calculated on a 5 km × 5 km grid, filtered for discarding extremely high events, and differentiated from week days to week-end days, with a specific insight upwind, over, and downwind Paris. Lightning flashes are more numerous in the North-East part of the domain and increasingly large events progressively concentrate over Paris and over some hills around. The former result indicates a possible influence of pollution on lightning activity downwind of Paris; the latter probably illustrates the influence of the urban heat island and of the relief on the convection strengthening. Furthermore, the number of positive CG flashes is rather uniformly distributed on the whole domain, except in the North-East where it appears somewhat relatively lower meanwhile negative CG are relatively more numerous in that region. This corresponds to a reduction in the percentage of positive CG downwind of Paris. Additionally, lightning activity appears weaker downwind of Paris during weekend days. A specific daily analysis of the lightning density in circles distributed along the direction of prevailing wind through Paris shows that the lightning activity appears higher downwind during the days most worked as Tuesday, Wednesday and Thursday. This higher electric activity persists up to about 40 km on Wednesday, and up to about 80 km on Tuesday and Thursday (most days worked). The electrification seems therefore more important downwind of Paris during the more polluted days.”
Citation: Sylvain Coquillat, Marie-Pierre Boussaton, Magalie Buguet, Dominique Lambert, Jean-François Ribaud, Andy Berthelot, Atmospheric Research, http://dx.doi.org/10.1016/j.atmosres.2012.10.032.
Greenland ice sheet runoff has increased since mid 1980s
Abstract: “The Greenland ice sheet (GrIS) contains the largest store of fresh water in the Northern Hemisphere, equivalent to ∼7.4 m of eustatic sea-level rise, but its impacts on current, past, and future sea level, ocean circulation, and European climate are poorly understood. Previous estimates of GrIS melt, from 26 yr of satellite observations and temperature-driven melt models over 48 yr, show increasing melt trends. There are, however, no runoff data of comparable duration with which to validate the relationship between the spatial extent of melting and runoff or temperature-based runoff models. Further, longer runoff records are needed to extend the melt pattern of Greenland to centennial timescales, enabling recent observations and trends to be put into a better historical context. We have developed a new GrIS runoff proxy by extracting information on relative salinity changes from annual growth bands of red coralline algae. We observed significant negative relationships between historic runoff, relative salinity, and marine summer temperature in Søndre Strømfjord, Greenland. We produce the first reconstruction of runoff from a section of the GrIS that discharges into Søndre Strømfjord over several decades (1939–2002) and record a trend of increasing reconstructed runoff since the mid 1980s. In situ summer marine temperatures followed an equivalent trend. We suggest that since A.D. 1939, atmospheric temperatures have been important in forcing runoff. These results show that our technique has significant potential to enhance understanding of runoff from large ice sheets as it will enable melt reconstruction over centennial to millennial timescales.”
Citation: Nicholas A. Kamenos, Trevor B. Hoey, Peter Nienow, Anthony E. Fallick and Thomas Claverie, Geology, v. 40 no. 12 p. 1095-1098, doi: 10.1130/G33405.1.
Multi-annual temperature forecasts in the ECMWF model are reliable
Highlights: •A reliability analysis has been applied to probabilistic decadal predictions. •Multi-annual temperature forecasts in the ECMWF model are, in general, reliable. •Long-term climate trends are a major but not the only source of skill.
Abstract: “The reliability of multi-year predictions of climate is assessed using probabilistic Attributes Diagrams for near-surface air temperature and sea surface temperature, based on 54 member ensembles of initialised decadal hindcasts using the ECMWF coupled model. It is shown that the reliability from the ensemble system is good over global land areas, Europe and Africa and for the North Atlantic, Indian Ocean and, to a lesser extent, North Pacific basins for lead times up to 6–9 years. North Atlantic SSTs are reliably predicted even when the climate trend is removed, consistent with the known predictability for this region. By contrast, reliability in the Indian Ocean, where external forcing accounts for most of the variability, deteriorates severely after detrending. More conventional measures of forecast quality, such as the anomaly correlation coefficient (ACC) of the ensemble mean, are also considered, showing that the ensemble has significant skill in predicting multi-annual temperature averages.”
Citation: Corti, S., A. Weisheimer, T. N. Palmer, F. J. Doblas-Reyes, and L. Magnusson (2012), Reliability of decadal predictions, Geophys. Res. Lett., 39, L21712, doi:10.1029/2012GL053354.
How are ecosystems doing in Chernobyl these days?
Abstract: “Animals are assumed to play a key role in ecosystem functioning through their effects on seed set, seed consumption, seed dispersal, and maintenance of plant communities. However, there are no studies investigating the consequences of animal scarcity on seed set, seed consumption and seed dispersal at large geographical scales. We exploited the unprecedented scarcity of pollinating bumblebees and butterflies in the vicinity of Chernobyl, Ukraine, linked to the effects of radiation on pollinator abundance, to test for effects of pollinator abundance on the ecosystem. There were considerably fewer pollinating insects in areas with high levels of radiation. Fruit trees and bushes (apple Malus domestica, pear Pyrus communis, rowan Sorbus aucuparia, wild rose Rosa rugosa, twistingwood Viburnum lantana, and European cranberry bush Viburnum opulus) that are all pollinated by insects produced fewer fruit in highly radioactively contaminated areas, partly linked to the local reduction in abundance of pollinators. This was the case even when controlling for the fact that fruit trees were generally smaller in more contaminated areas. Fruit-eating birds like thrushes and warblers that are known seed dispersers were less numerous in areas with lower fruit abundance, even after controlling for the effects of radiation, providing a direct link between radiation, pollinator abundance, fruit abundance and abundance of frugivores. Given that the Chernobyl disaster happened 25 years ago, one would predict reduced local recruitment of fruit trees if fruit set has been persistently depressed during that period; indeed, local recruitment was negatively related to the level of radiation and positively to the local level of fruit set. The patterns at the level of trees were replicated at the level of villages across the study site. This study provides the first large-scale study of the effects of a suppressed pollinator community on ecosystem functioning.”
Citation: Anders Pape Møller, Florian Barnier, Timothy A. Mousseau, Oecologia, December 2012, Volume 170, Issue 4, pp 1155-1165, DOI: 10.1007/s00442-012-2374-0.
Trying to see global warming locally
Highlights: •Significant shift in observed temperatures. •Large parts of the Earth have seen a significant change.
Abstract: “The global average temperature of the Earth has increased, but year-to-year variability in local climates impedes the identification of clear changes in observations and human experience. For a signal to become obvious in data records or in a human lifetime it needs to be greater than the noise of variability and thereby lead to a significant shift in the distribution of temperature. We show that locations with the largest amount of warming may not display a clear shift in temperature distributions if the local variability is also large. Based on observational data only we demonstrate that large parts of the Earth have experienced a significant local shift towards warmer temperatures in the summer season, particularly at lower latitudes. We also show that these regions are similar to those that are found to be significant in standard detection methods, thus providing an approach to link locally significant changes more closely to impacts.”
Citation: Mahlstein, I., G. Hegerl, and S. Solomon (2012), Emerging local warming signals in observational data, Geophys. Res. Lett., 39, L21711, doi:10.1029/2012GL053952.
Temperature of ultimate happiness is 13.9 degrees Celsius
Abstract: “This paper investigates the influence of weather on happiness. While previous studies have examined climatic influence by comparing the well-being of people living in different regions, this paper focuses on how daily changes in weather affect individuals living in a single location. Our data set consists of 516 days of data on 75 students from Osaka University. Daily information on outside events, as well as the daily physical condition and individual characteristics of the respondents, are used as controls. Subjective happiness is related to temperature: in a quadratic model, happiness is maximized at 13.9 degrees Celsius. The effects of other meteorological variables—humidity, wind speed, precipitation, and sunshine—are not significant. The sensitivity of happiness to temperature also depends on attributes such as sex, age, and academic department. Happiness is more strongly affected by current temperature than by average temperature over the day. While enjoyment (a positive affect measure) is affected by weather in a similar way to happiness, sadness and depression (negative affect measures) behave somewhat differently.”
Citation: Yoshiro Tsutsui, Weather, Climate, and Society 2012, doi: http://dx.doi.org/10.1175/WCAS-D-11-00052.1.
Recently delayed spring phenology in temperate biomes of China
Abstract: “Understanding spring phenology changes in response to the rapid climate change at biome-level is crucial for projecting regional ecosystem carbon exchange and climate–biosphere interactions. In this study, we assessed the long–term changes and responses to changing climate of the spring phenology in six temperate biomes of China by analyzing the GIMMS NOAA/AVHRR Normalized Difference Vegetation Index (NDVI) and concurrent mean temperature and precipitation data for 1982–2006. Results show that the spring phenology trends in the six temperate biomes are not continuous throughout the 25-year period. The spring phenology in most areas of the six biomes showed obvious advancing trends (ranging from -0.09 to -0.65 day year-1) during the 1980s and early 1990s, but has subsequently suffered consistently delaying trends (ranging from 0.22 to 1.22 day year–1). Changes in spring (February–April) temperature are the dominating factor governing the pattern of spring vegetation phenology in the temperate biomes of China. The recently delayed spring phenology in these temperate biomes has been mainly triggered by the stalling or reversal of the warming trend in spring temperatures. Results in this study also reveal that precipitation during November–January can explain 16.1% (p < 0.05), 20.9% (p < 0.05) and 14.2% (p < 0.05) of the variations in temperate deciduous forest, temperate steppe and temperate desert, respectively, highlighting the important role of winter precipitation in regulating changes in the spring vegetation phenology of water–limited biomes.”
Citation: Xiuchen Wu, Hongyan Liu, Global Change Biology, DOI: 10.1111/gcb.12086.
Past and future sea-level change from the surface mass balance of glaciers
Abstract: “We present estimates of sea-level change caused by the global surface mass balance of glaciers, based on the reconstruction and projection of the surface mass balance of all the individual glaciers of the world, excluding the ice sheets in Greenland and Antarctica. The model is validated using a leave-one-glacier-out cross-validation scheme against 3997 observed surface mass balances of 255 glaciers, and against 756 geodetically observed, temporally integrated volume and surface area changes of 341 glaciers. When forced with observed monthly precipitation and temperature data, the glaciers of the world are reconstructed to have lost mass corresponding to 114 ± 5 mm sea-level equivalent (SLE) between 1902 and 2009. Using projected temperature and precipitation anomalies from 15 coupled general circulation models from the Coupled Model Intercomparison Project phase 5 (CMIP5) ensemble, they are projected to lose an additional 148 ± 35 mm SLE (scenario RCP26), 166 ± 42 mm SLE (scenario RCP45), 175 ± 40 mm SLE (scenario RCP60), or 217 ± 47 mm SLE (scenario RCP85) during the 21st century. Based on the extended RCP scenarios, glaciers are projected to approach a new equilibrium towards the end of the 23rd century, after having lost either 248 ± 66 mm SLE (scenario RCP26), 313 ± 50 mm SLE (scenario RCP45), or 424 ± 46 mm SLE (scenario RCP85). Up until approximately 2100, ensemble uncertainty within each scenario is the biggest source of uncertainty for the future glacier mass loss; after that, the difference between the scenarios takes over as the biggest source of uncertainty. Ice mass loss rates are projected to peak 2040 ∼ 2050 (RCP26), 2050 ∼ 2060 (RCP45), 2070 ∼ 2090 (RCP60), or 2070 ∼ 2100 (RCP85).”
Citation: Marzeion, B., Jarosch, A. H., and Hofer, M.: Past and future sea-level change from the surface mass balance of glaciers, The Cryosphere, 6, 1295-1322, doi:10.5194/tc-6-1295-2012, 2012.
Other studies from last week
CLASSIC OF THE WEEK: Glaisher (1848)
Abstract: No abstract. Note that full text might not be freely accessible after November 29, 2012.
Citation: James Glaisher, Phil. Trans. R. Soc. Lond. January 1, 1848 138 125-139; doi:10.1098/rstl.1848.0008.
About this series. When each paper is published, it is notified in AGW Observer Facebook page and Twitter page. Here’s the archive for the research papers of previous weeks. If this sort of thing interests you, be sure to check out A Few Things Illconsidered. They also have a weekly posting containing lots of links to new research and other climate related news.