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New research – temperature (October 18, 2016)

Posted by Ari Jokimäki on October 18, 2016

Some of the latest papers on temperature (related to climate) 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.


Comparing tropospheric warming in climate models and satellite data (Santer et al. 2016)

Abstract: We use updated and improved satellite retrievals of the temperature of the mid- to upper troposphere (TMT) to address key questions about the size and significance of TMT trends, agreement with model-derived TMT values, and whether models and satellite data show similar vertical profiles of warming. A recent study claimed that TMT trends over 1979 and 2015 are three times larger in climate models than in satellite data, but did not correct for the contribution TMT trends receive from stratospheric cooling. Here we show that the average ratio of modeled and observed TMT trends is sensitive to both satellite data uncertainties and to model-data differences in stratospheric cooling. When the impact of lower stratospheric cooling on TMT is accounted for, and when the most recent versions of satellite datasets are used, the previously claimed ratio of three between simulated and observed near-global TMT trends is reduced to ≈ 1.7. Next, we assess the validity of the statement that satellite data show no significant tropospheric warming over the last 18 years. This claim is not supported by our analysis: in five out of six corrected satellite TMT records, significant global-scale tropospheric warming has occurred within the last 18 years. Finally, we address long-standing concerns regarding discrepancies in modeled and observed vertical profiles of warming in the tropical atmosphere. We show that amplification of tropical warming between the lower and mid- to upper troposphere is now in close agreement in the average of 37 climate models and in one updated satellite record.

Deep and Abyssal Ocean Warming from 35 years of Repeat Hydrography (Desbruyères et al. 2016)

Abstract: Global and regional ocean warming deeper than 2000 m is investigated using 35 years of sustained repeat hydrographic survey data starting in 1981. The global long-term temperature trend below 2000 m, representing the time period 1991–2010, is equivalent to a mean heat flux of 0.065 ± 0.040 W m−2 applied over the Earth’s surface area. The strongest warming rates are found in the abyssal layer (4000–6000 m), which contributes to one third of the total heat uptake with the largest contribution from the Southern and Pacific Oceans. A similar regional pattern is found in the deep layer (2000–4000 m), which explains the remaining two thirds of the total heat uptake yet with larger uncertainties. The global average warming rate did not change within uncertainties pre-2000 versus post-2000, whereas ocean average warming rates decreased in the Pacific and Indian Oceans and increased in the Atlantic and Southern Oceans.

The contribution of greenhouse gases to the recent slowdown in global-mean temperature trends (Checa-Garcia et al. 2016)

Abstract: The recent slowdown in the rate of increase in global-mean surface temperature (GMST) has generated extensive discussion, but little attention has been given to the contribution of time-varying trends in greenhouse gas concentrations. We use a simple model approach to quantify this contribution. Between 1985 and 2003, greenhouse gases (including well-mixed greenhouse gases, tropospheric and stratospheric ozone, and stratospheric water vapour from methane oxidation) caused a reduction in GMST trend of around 0.03–0.05 K decade−1 which is around 18%–25% of the observed trend over that period. The main contributors to this reduction are the rapid change in the growth rates of ozone-depleting gases (with this contribution slightly opposed by stratospheric ozone depletion itself) and the weakening in growth rates of methane and tropospheric ozone radiative forcing. Although CO2 is the dominant greenhouse gas contributor to GMST trends, the continued increase in CO2 concentrations offsets only about 30% of the simulated trend reduction due to these other contributors. These results emphasize that trends in non-CO2 greenhouse gas concentrations can make significant positive and negative contributions to changes in the rate of warming, and that they need to be considered more closely in analyses of the causes of such variations.

The Stancari air thermometer and the 1715–1737 record in Bologna, Italy (Camuffo et al. 2016)

Abstract: This paper is focused on the closed-tube Stancari air thermometer that was developed at the beginning of the eighteenth century as an improvement of the Amontons thermometer, and used to record the temperature in Bologna, Italy, from 1715 to 1737. The problems met with this instrument, its calibration and the building technology in the eighteenth century are discussed in order to correct the record. The used methodological approach constitutes a useful example for other early series. The analysis of this record shows that the temperature in Bologna was not different from the 1961–1990 reference period. This result is in line with the contemporary record taken in Padua, Italy, confirming that this period of the Little Ice Age was not cold in the Mediterranean area.

Twenty-five winters of unexpected Eurasian cooling unlikely due to Arctic sea-ice loss (McCusker et al. 2016)

Abstract: Surface air temperature over central Eurasia decreased over the past twenty-five winters at a time of strongly increasing anthropogenic forcing and Arctic amplification. It has been suggested that this cooling was related to an increase in cold winters due to sea-ice loss in the Barents–Kara Sea. Here we use over 600 years of atmosphere-only global climate model simulations to isolate the effect of Arctic sea-ice loss, complemented with a 50-member ensemble of atmosphere–ocean global climate model simulations allowing for external forcing changes (anthropogenic and natural) and internal variability. In our atmosphere-only simulations, we find no evidence of Arctic sea-ice loss having impacted Eurasian surface temperature. In our atmosphere–ocean simulations, we find just one simulation with Eurasian cooling of the observed magnitude but Arctic sea-ice loss was not involved, either directly or indirectly. Rather, in this simulation the cooling is due to a persistent circulation pattern combining high pressure over the Barents–Kara Sea and a downstream trough. We conclude that the observed cooling over central Eurasia was probably due to a sea-ice-independent internally generated circulation pattern ensconced over, and nearby, the Barents–Kara Sea since the 1980s. These results improve our knowledge of high-latitude climate variability and change, with implications for our understanding of impacts in high-northern-latitude systems.

Other papers

New method of estimating temperatures near the mesopause region using meteor radar observations (Lee et al. 2016)

Estimated influence of urbanization on surface warming in Eastern China using time-varying land use data (Liao et al. 2016)

The influence of winter and summer atmospheric circulation on the variability of temperature and sea ice around Greenland (Ogi et al. 2016)

A cold and fresh ocean surface in the Nordic Seas during MIS 11: Significance for the future ocean (Kandiano et al. 2016)

Observed and projected sea surface temperature seasonal changes in the Western English Channel from satellite data and CMIP5 multi-model ensemble (L’Hévéder et al. 2016)

Historical ocean reanalyses (1900–2010) using different data assimilation strategies (Yang et al. 2016)

Analysis of the warmest Arctic winter, 2015-2016 (Cullather et al. 2016)

The influence of synoptic circulations and local processes on temperature anomalies at three French observatories (Dione et al. 2016)

Ocean atmosphere thermal decoupling in the eastern equatorial Indian ocean (Joseph et al. 2016)

Changes of the time-varying percentiles of daily extreme temperature in China (Li et al. 2016)

High atmospheric horizontal resolution eliminates the wind-driven coastal warm bias in the southeastern tropical Atlantic (Milinski et al. 2016)

Effects of Natural Variability of Seawater Temperature, Time Series Length, Decadal Trend and Instrument Precision on the Ability to Detect Temperature Trends (Schlegel & Smit, 2016)

Interhemispheric SST gradient trends in the Indian Ocean prior to and during the recent global warming hiatus (Dong & McPhaden, 2016)

Temperature and precipitation extremes in century-long gridded observations, reanalyses, and atmospheric model simulations (Donat et al. 2016)

Atmospheric structure favoring high sea surface temperatures in the western equatorial Pacific (Wirasatriya et al. 2016)

Spatial and temporal changes in daily temperature extremes in China during 1960–2011 (Shen et al. 2016)

Disaggregation of Remotely Sensed Land Surface Temperature: A New Dynamic Methodology (Zhan et al. 2016)

Impact of high-resolution sea surface temperature and urban data on estimations of surface air temperature in a regional climate (Adachi et al. 2016)

Trends of urban surface temperature and heat island characteristics in the Mediterranean (Benas et al. 2016)

Impacts of urbanization on summer climate in China: An assessment with coupled land-atmospheric modeling (Cao et al. 2016)

The impact of climatic and non-climatic factors on land surface temperature in southwestern Romania (Roşca et al. 2016)

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

New research – past climate (October 14, 2016)

Posted by Ari Jokimäki on October 14, 2016

Some of the latest papers on past climate changes 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.


Proxy-based Northern Hemisphere temperature reconstruction for the mid-to-late Holocene (Pei et al. 2016)

Abstract: The observed late twentieth century warming must be assessed in relation to natural long-term variations of the climatic system. Here, we present a Northern Hemisphere (NH) temperature reconstruction for the mid-to-late Holocene of the past 6000 years, based on a synthesis of existing paleo-temperature proxies that are capable of revealing centennial-scale variability. This includes 56 published temperature records across the NH land areas, with a sampling resolution ranging from 1 to 100 years and a time span of at least 1000 years. The composite plus scale (CPS) method is adopted with spatial weighting to develop the NH temperature reconstruction. Our reconstruction reveals abrupt cold epochs that match well the Bond events during the past 6000 years. The study further reveals two prominent cycles in NH temperature: 1700–2000-year cycle during the mid-to-late Holocene and 1200–1500-year cycle during the past 3500 years. Our reconstruction indicates that the late twentieth century NH temperature and its rate of warming are both unprecedentedly high over the past 5000 years. By comparing our reconstruction with the projected temperature increase scenarios, we find that temperature by the end of the twenty-first century would likely exceed any peaks during the mid-to-late Holocene.

How warm was Greenland during the last interglacial period? (Landais et al. 2016)

Abstract: The last interglacial period (LIG,~129–116 thousand years ago) provides the most recent case study of multimillennial polar warming above the preindustrial level and a response of the Greenland and Antarctic ice sheets to this warming, as well as a test bed for climate and ice sheet models. Past changes in Greenland ice sheet thickness and surface temperature during this period were recently derived from the North Greenland Eemian Ice Drilling (NEEM) ice core records, northwest Greenland. The NEEM paradox has emerged from an estimated large local warming above the preindustrial level (7.5 ± 1.8 °C at the deposition site 126 kyr ago without correction for any overall ice sheet altitude changes between the LIG and the preindustrial period) based on water isotopes, together with limited local ice thinning, suggesting more resilience of the real Greenland ice sheet than shown in some ice sheet models. Here, we provide an independent assessment of the average LIG Greenland surface warming using ice core air isotopic composition (δ15N) and relationships between accumulation rate and temperature. The LIG surface temperature at the upstream NEEM deposition site without ice sheet altitude correction is estimated to be warmer by +8.5 ± 2.5 °C compared to the preindustrial period. This temperature estimate is consistent with the 7.5 ± 1.8 °C warming initially determined from NEEM water isotopes but at the upper end of the preindustrial period to LIG temperature difference of +5.2 ± 2.3 °C obtained at the NGRIP (North Greenland Ice Core Project) site by the same method. Climate simulations performed with present-day ice sheet topography lead in general to a warming smaller than reconstructed, but sensitivity tests show that larger amplitudes (up to 5 °C) are produced in response to prescribed changes in sea ice extent and ice sheet topography.

Response of Central European SST to atmospheric pCO2 forcing during the Oligocene – A combined proxy data and numerical climate model approach (Walliser et al. 2016)

Abstract: CO2-induced global warming will affect seasonal to decadal temperature patterns. Expected changes will be particularly strong in extratropical regions where temperatures will increase at faster rates than at lower latitudes. Despite that, it is still poorly constrained how precisely short-term climate dynamics will change in a generally warmer world, particularly in nearshore surface waters in the extratropics, i.e., the ecologically most productive regions of the ocean on which many human societies depend. Specifically, a detailed knowledge of the relationship between pCO2 and seasonal SST is crucial to understand interactions between the ocean and the atmosphere. In the present investigation, we have studied for the first time how rising atmospheric pCO2 levels forced surface temperature changes in Central Europe (paleolatitude ~ 45 °N) during the mid-Oligocene (from ca. 31 to 25 Ma), a time interval of Earth history during which global conditions were comparable to those predicted for the next few centuries. For this purpose, we computed numerical climate models for the Oligocene (winter, summer, annual average) assuming an atmospheric carbon dioxide rise from 400 to 560 ppm (current level to two times pre-industrial levels, PAL) and from 400 to 840 ppm (= three times PAL), respectively. These models were compared to seasonally resolved sea surface temperatures (SST) reconstructed from δ18O values of fossil bivalve shells (Glycymeris planicostalis, G. obovata, Palliolum pictum, Arctica islandica and Isognomon maxillata sandbergeri) and shark teeth (Carcharias cuspidata, C. acutissima and Physogaleus latus) collected from the shallow water deposits of the Mainz and Kassel Basins (Germany). Multi-taxon oxygen isotope-based reconstructions suggest a gradual rise of temperatures in surface waters (upper 30 to 40 m), on average, by as much as 4 °C during the Rupelian stage followed by a 4 °C cooling during the Chattian stage. Seasonal temperature amplitudes increased by ca. 2 °C during the warmest time interval of the Rupelian stage, with warming being more pronounced during summer (5 °C) than during winter (3 °C). According to numerical climate simulations, the warming of surface waters during the early Oligocene required a CO2 increase by at least 160 ppm, i.e., 400 ppm to 560 ppm. Given that atmospheric carbon dioxide levels predicted for the near future will likely exceed this value significantly, the Early Oligocene warming gives a hint of the possible future climate in Central Europe under elevated CO2 levels.

Low Florida coral calcification rates in the Plio-Pleistocene (Brachert et al. 2016)

Abstract: In geological outcrops and drill cores from reef frameworks, the skeletons of scleractinian corals are usually leached and more or less completely transformed into sparry calcite because the highly porous skeletons formed of metastable aragonite (CaCO3) undergo rapid diagenetic alteration. Upon alteration, ghost structures of the distinct annual growth bands often allow for reconstructions of annual extension ( =  growth) rates, but information on skeletal density needed for reconstructions of calcification rates is invariably lost. This report presents the bulk density, extension rates and calcification rates of fossil reef corals which underwent minor diagenetic alteration only. The corals derive from unlithified shallow water carbonates of the Florida platform (south-eastern USA), which formed during four interglacial sea level highstands dated approximately 3.2, 2.9, 1.8, and 1.2 Ma in the mid-Pliocene to early Pleistocene. With regard to the preservation, the coral skeletons display smooth growth surfaces with minor volumes of marine aragonite cement within intra-skeletal porosity. Within the skeletal structures, voids are commonly present along centres of calcification which lack secondary cements. Mean extension rates were 0.44 ± 0.19 cm yr−1 (range 0.16 to 0.86 cm yr−1), mean bulk density was 0.96 ± 0.36 g cm−3 (range 0.55 to 1.83 g cm−3) and calcification rates ranged from 0.18 to 0.82 g cm−2 yr−1 (mean 0.38 ± 0.16 g cm−2 yr−1), values which are 50 % of modern shallow-water reef corals. To understand the possible mechanisms behind these low calcification rates, we compared the fossil calcification rates with those of modern zooxanthellate corals (z corals) from the Western Atlantic (WA) and Indo-Pacific calibrated against sea surface temperature (SST). In the fossil data, we found a widely analogous relationship with SST in z corals from the WA, i.e. density increases and extension rate decreases with increasing SST, but over a significantly larger temperature window during the Plio-Pleistocene. With regard to the environment of coral growth, stable isotope proxy data from the fossil corals and the overall structure of the ancient shallow marine communities are consistent with a well-mixed, open marine environment similar to the present-day Florida Reef Tract, but variably affected by intermittent upwelling. Upwelling along the platform may explain low rates of reef coral calcification and inorganic cementation, but is too localised to account also for low extension rates of Pliocene z corals throughout the tropical WA region. Low aragonite saturation on a more global scale in response to rapid glacial–interglacial CO2 cyclicity is also a potential factor, but Plio-Pleistocene atmospheric pCO2 is generally believed to have been broadly similar to the present day. Heat stress related to globally high interglacial SST only episodically moderated by intermittent upwelling affecting the Florida platform seems to be another likely reason for low calcification rates. From these observations we suggest some present coral reef systems to be endangered from future ocean warming.

The ‘Little Ice Age’ in the Himalaya: A review of glacier advance driven by Northern Hemisphere temperature change (Rowan, 2016)

Abstract: Northern Hemisphere cooling between 1400 and 1900 in the Common Era (CE) resulted in the expansion of glaciers during a period known as the ‘Little Ice Age’ (LIA). Early investigation of recent advances of Himalayan glaciers assumed that these events were synchronous with LIA advances identified in Europe, based on the appearance and position of moraines and without numerical age control. However, applications of Quaternary dating techniques such as terrestrial cosmogenic nuclide dating have allowed researchers to determine numerical ages for these young moraines and clarify when glacial maxima occurred. This paper reviews geochronological evidence for the last advance of glaciers in the Himalaya. The 66 ages younger than 2000 years (0–2000 CE) calculated from 138 samples collected from glacial landforms demonstrate that peak moraine building occurred between 1300 and 1600 CE, slightly earlier than the coldest period of Northern Hemisphere air temperatures. The timing of LIA advances varied spatially, likely influenced by variations in topography and meteorology across and along the mountain range. Palaeoclimate proxies indicate cooling air temperatures from 1300 CE leading to a southward shift in the Asian monsoon, increased Westerly winter precipitation and generally wetter conditions across the range around 1400 and 1800 CE. The last advance of glaciers in the Himalaya during a period of variable climate resulted from cold Northern Hemisphere air temperatures and was sustained by increased snowfall as atmospheric circulation reorganised in response to cooling during the LIA.

Other papers

Dendroclimatology and historical climatology of Voronezh region, European Russia, since 1790s (Matskovsky et al. 2016)

Can stable oxygen and hydrogen isotopes from Australian subfossil Chironomus head capsules be used as proxies for past temperature change? (Chang et al. 2016)

Global deep water circulation between 2.4 and 1.7 Ma and its connection to the onset of Northern Hemisphere Glaciation (Du et al. 2016)

Evidence of temperature and precipitation change over the past 100 years in a high-resolution pollen record from the boreal forest of Central European Russia (Olchev et al. 2016)

The Bølling-age Blomvåg Beds, western Norway: implications for the Older Dryas glacial re-advance and the age of the deglaciation (Mangerud et al. 2016)

Impact of meltwater on high-latitude early Last Interglacial climate (Stone et al. 2016)

Late Miocene global cooling and the rise of modern ecosystems (Herbert et al. 2016)

On the palaeoclimatic potential of a millennium-long oak ring width chronology from Slovakia (Prokop et al. 2016)

A 414-year tree-ring-based April–July minimum temperature reconstruction and its implications for the extreme climate events, northeast China (Lyu et al. 2016)

Interactions between climate change and human activities during the early to mid-Holocene in the eastern Mediterranean basins (Berger et al. 2016)

The effect of greenhouse gas concentrations and ice sheets on the glacial AMOC in a coupled climate model (Klockmann et al. 2016)

The MMCO-EOT conundrum: same benthic δ18O, different CO2 (Stap et al. 2016)

Bayesian hierarchical regression analysis of variations in sea surface temperature change over the past million years (Snyder, 2016)

Leaf margin analysis of Chinese woody plants and the constraints on its application to palaeoclimatic reconstruction (Li et al. 2016)

The demise of the early Eocene greenhouse – Decoupled deep and surface water cooling in the eastern North Atlantic (Bornemann et al. 2016)

Impact of ice sheet meltwater fluxes on the climate evolution at the onset of the Last Interglacial (Goelzer et al. 2016)

The Response of Phanerozoic Surface Temperature to Variations in Atmospheric Oxygen Concentration (Payne et al. 2016)

Abrupt Bølling warming and ice saddle collapse contributions to the Meltwater Pulse 1a rapid sea level rise (Gregoire et al. 2016)

Early- to mid-Holocene forest-line and climate dynamics in southern Scandes mountains inferred from contrasting megafossil and pollen data (Paus & Haugland, 2016)

Low frequency Pliocene climate variability in the eastern Nordic Seas (Risebrobakken et al. 2016)

Water and carbon stable isotope records from natural archives: a new database and interactive online platform for data browsing, visualizing and downloading (Bolliet et al. 2016)

Diagenetic disturbances of marine sedimentary records from methane-influenced environments in the Fram Strait as indications of variation in seep intensity during the last 35 000 years (Sztybor & Rasmussen, 2016)

Evidence of solar activity and El Niño signals in tree rings of Araucaria araucana and A. angustifolia in South America (Perone et al. 2016)

Simulated response of the mid-Holocene Atlantic Meridional Overturning Circulation in ECHAM6-FESOM/MPIOM (Shi & Lohmann, 2016)

Holocene fire regimes and treeline migration rates in sub-arctic Canada (Sulphur et al. 2016)

Hydroclimatic variability on the Indian-subcontinent in the past millennium: Review and assessment (Dixit & Tandon, 2016)

Interglacial/glacial changes in coccolith-rich deposition in the SW Pacific Ocean: An analogue for a warmer world? (Duncan et al. 2016)

Tibetan Plateau Geladaindong black carbon ice core record (1843‒1982): Recent increases due to higher emissions and lower snow accumulation (Jenkins et al. 2016)

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

Climate related papers in Journal of the Optical Society of America

Posted by Ari Jokimäki on October 12, 2016

Journal of the Optical Society of America (JOSA) was published between 1917 and 1983. After that it continued as two journals: JOSA A: Optics and Image Science and JOSA B: Optical Physics. This selection contains 225 climate related papers published in JOSA. There are not many papers related directly to climate, but most of the papers below are studying the infrared absorption properties of greenhouse gases.

Here are the selected papers:

Feature Issue on Meteorological Optics: Foreword (Bohren et al. 1983)

Inversion of superior mirage data to compute temperature profiles (Lehn, 1983)

Colors of snow, frozen waterfalls, and icebergs (Bohren, 1983)

Rainfall-induced optical phase fluctuations in the atmosphere (Yura et al. 1983)

Telluric spectra from 4690 to 5525 Å in a humid atmosphere (Rajaratnam & Lua, 1983)

Experimental Doppler-limited spectra of the ν2 bands of H216O, H217O, H218O, and HDO by Fourier-transform spectroscopy: secondary wave-number standards between 1066 and 2296 cm−1 (Guelachvili, 1983)

Radiative properties of optically anisotropic spheres and their climatic implications (Fymat, 1982)

Spatial-frequency- and wavelength-dependent effects of aerosols on the atmospheric modulation transfer function (Kopeika, 1982)

Spatial-frequency dependence of scattered background light: The atmospheric modulation transfer function resulting from aerosols (Kopeika, 1982)

Maximum-likelihood optimization of a Fabry–Perot interferometer for thermospheric temperature and wind measurements (Jahn et al. 1982)

Wavelength variation of visible and near-infrared resolution through the atmosphere: dependence on aerosol and meteorological conditions (Kopeika et al. 1981)

Refractive-index and absorption fluctuations in the infrared caused by temperature, humidity, and pressure fluctuations (Hill et al. 1980)

Vertical path atmospheric MTF measurements (Walters et al. 1979)

Single-particle correlation techniques for remote measurement of wind speed: Aerosol condition and measurement rate (Bartlett & She, 1979)

Modified spectrum of atmospheric temperature fluctuations and its application to optical propagation (Hill & Clifford, 1978)

Adiabatic pressure dependence of the 2.7 and 1.9 μm water vapor bands (Mathai et al. 1977)

Very-high-resolution far-infrared measurements of atmospheric emission from aircraft (Carli et al. 1977)

Submillimeter wave spectroscopy of the atmosphere (Harries, 1977)

Laws of optics at high irradiance. II. Experiments with SF6 at normal incidence (Thomason & Macomber, 1977)

Infrared absorption coefficient of H2SO4 vapor from 1190 to 1260 cm−1 (Majkowski, 1977)

Optical constants of water in the infrared: Influence of temperature (Pinkley et al. 1977)

9.6 μm ozone band (ν3) intensity (Bartman et al. 1976)

Optical properties of sea water in the infrared (Pinkley & Willims, 1976)

Raman-scattering cross sections for water vapor (Penney & Lapp, 1976)

The infrared optical constants of sulfuric acid at 250 K (Pinkley & Willims, 1976)

High-resolution methane ν3-band spectra using a stabilized tunable difference-frequency laser system (Pine, 1976)

Use of rainfall-induced optical scintillations to measure path-averaged rain parameters (Wang & Clifford, 1975)

6.3 μm water-vapor-band derivatives (Hendrickson et al. 1974)

Thermodynamic derivatives of infrared absorptance (Broersma & Walls, 1974)

Absolute rotational Raman cross sections for N2, O2, and CO2 (Penney et al. 1974)

Scattering-independent determination of the thermal-emission profile of a planetary atmosphere and related radiative-equilibrium considerations (Fymat, 1974)

Broadening of infrared absorption lines at reduced temperatures, III. Nitrous oxide (Tubbs & Williams, 1973)

Balloon-borne infrared measurements of the vertical distribution of N2O in the atmosphere (Goldman et al. 1973)

Influence of Temperature on the Spectrum of Water (Hale et al. 1972)

Measurements of Turbulence Profiles in the Troposphere (Bufton et al. 1972)

Irradiance Fluctuations in Optical Transmission through the Atmosphere (Lawrence, 1972)

Intensity–Half-Width Products for Seven Lines in the 6.3-μm Water-Vapor Band (Fridovich & Kinard, 1972)

Broadening of Infrared Absorption Lines at Reduced Temperatures, II. Carbon Monoxide in an Atmosphere of Carbon Dioxide (Tubbs & Williams, 1972)

Broadening of Infrared Absorption Lines at Reduced Temperatures: Carbon Dioxide (Tubbs & Williams, 1972)

Irradiance Fluctuations in Optical Transmission through the Atmosphere (Torrieri & Taylor, 1972)

Lambert Absorption Coefficients of Water in the Infrared (Robertson & Williams, 1971)

Optical Constants of Water in the Infrared (Rusk et al. 1971)

Absorption of Infrared Radiant Energy by CO2 and H2O, V. Absorption by CO2 between 1100 and 1835 cm−1 (9.1–5.5 μm) (Burch & Gryvnak, 1971)

Dispersion of Carbon Dioxide (Old et al. 1971)

Abundance of N2O in the Atmosphere between 4.5 and 13.5 km (Goldman et al. 1970)

Line Strengths in the ν3 Band of Water Vapor (Ben-Aryeh, 1970)

Infrared Spectral Absorption Coefficients for Water Vapor (Heroet & Muiriiead, 1970)

Foreign-Gas Broadening of HF by CO2 (Shaw & Lovell, 1969)

Strengths of 31 Water-Vapor Lines between 1617 and 1429 cm−1 (Krakow & Healy, 1969)

Refractive Index of Water in the Infrared (Querry et al. 1969)

Spectral Emissivity of the 3.3-μ Band of Methane at Elevated Temperatures (Goldman et al. 1969)

Presence of HNO3 in the Upper Atmosphere (Murcray et al. 1969)

Strengths of Twenty Lines in the ν3 Band of Water Vapor (Babrov & Healy, 1969)

Spectral Emissivity of NO in the Infrared (Oppenheim et al. 1969)

Absorption of Infrared Radiant Energy by CO2 and H2O. IV. Shapes of Collision-Broadened CO2 Lines (Burch et al. 1969)

Infrared Absorptance of Ammonia—20 to 35 Microns (Walsh, 1969)

Positions, Intensities, and Widths of Water-Vapor Lines between 475 and 692 cm−1 (Izatt et al. 1969)

Model for a Clear Atmosphere (Gordon, 1969)

Determination of the Temperature Profile in an Atmosphere from its Outgoing Radiance (Chahine, 1968)

Absorption of Infrared Radiant Energy by CO2 and H2O. III. Absorption by H2O between 0.5 and 36 cm−1 (278 μ−2 cm) (Burch, 1968)

Visual Haze Observed at High Altitudes (Clark, 1968)

Radiance of Sea and Sky in the Infrared Window 800–1200 cm−1 (Saunders, 1968)

Determination of CO2 Line Parameters Using a CO2–N2–He Laser (Oppenheim & Devir, 1968)

Absorption of Infrared Radiation by CO2 and H2O. II. Absorption by CO2 between 8000 and 10 000 cm−1 (1–1.25 Microns) (Burch et al. 1968)

Low-Resolution Determination of the Strength of the 667-cm−1 CO2 Band (Harward & Patty, 1968)

Strengths of Forty-two Lines in the ν1 and ν3 Bands of Water Vapor (Babrov & Casden, 1968)

Photoionization and Absorption Coefficients of N2O (Cook et al. 1968)

Influence of Wind and Cloudiness on Terrestrial Scintillation (Paperlein, 1967)

Integrated Intensity of 3.3-μ Band of Methane (Finkman et al. 1967)

Absorption of Infrared Radiation by CO2 and H2O. Experimental Techniques (Burch et al. 1967)

Self-Broadening Effects in the Infrared Bands of Gases (Anderson et al. 1967)

High-Temperature Spectral Emissivities and Total Intensities of the 15-μ Band System of CO2 (Ludwig et al. 1966)

Indirect Method for Measuring Spectral Linewidth, with Application to N2O (Oppenheim & Goldman, 1966)

Total Absorption Cross Sections of CO and CO2 in the Region 550–200 Å (Cairns & Samson, 1966)

Infrared Spectral Reflectance of Frost (Keegan & Weidner, 1966)

Spectroradiometric and Colorimetric Characteristics of Daylight in the Southern Hemisphere: Pretoria, South Africa (Winch et al. 1966)

Transmittance of Water Vapor—14 to 20 Microns (Stauffer & Walsh, 1966)

Spectral-Emissivity Measurements of the 4.3-μ CO2 Band between 2650° and 3000°K (Ferriso et al. 1966)

Far-Infrared Spectrum of Liquid Water (Draegert et al. 1966)

Absorption of Solar Radiation by Atmospheric Carbon Dioxide (Kyle et al. 1965)

Ultraviolet Spectral Energy Distribution of Sunlight (Searle & Hirt, 1965)

Daylight and Correlated Color Temperature (Wright, 1965)

Absorption of 3.39-Micron Helium–Neon Laser Emission by Methane in the Atmosphere (Edwards & Burch, 1965)

Spectral Energy Distribution of Daylight (Condit & Grum, 1964)

Infrared Emissivity of Carbon Dioxide (2.7-μ Band) (Malkmus, 1964)

Spectral Emissivities and Integrated Intensities of the 2.7- μ CO2 Band between 1200° and 1800°K (Ferriso & Ludwig, 1964)

Abundance of Methane in the Earth’s Atmosphere (Fink et al. 1964)

Emissivity of Carbon Dioxide at 4.3 μ (Davies, 1964)

Absorption Cross Sections of Argon and Methane between 600 and 170 Å (Rustgi, 1964)

Interpretation of Infrared Spectral Absorptance Measurements and Calculations for HCl (Malkmus et al. 1964)

Errors in Spectral Absorption Measurements Due to Absorbing Species in the Atmosphere (Maclay & Babrov, 1964)

Computed Intensity and Polarization of Light Scattered Outwards from the Earth and an Overlying Aerosol (Fraser, 1964)

Variation of the Infrared Solar Spectrum between 2800 and 5100 cm−1 with Altitude (Murcray et al. 1964)

Pure Rotational Absorption Spectrum of Hydrogen Fluoride Vapor between 22 and 250 μ (Rothschild, 1964)

Broadening of the ν3 Lines of HCN Due to Argon, Carbon Dioxide, and Hydrogen Chloride (Thibault et al. 1963)

The Radiance of the Earth and its Atmosphere Measured by Interference Spectroscopy (Persky & Zachor, 1963)

Infrared Emissivity of Carbon Dioxide (4.3-μ Band) (Malkmus, 1963)

Experimental and Theoretical Infrared Spectral Absorptance of HCl at Various Temperatures (Babrov, 1963)

Cirrus Infrared Reflection Measurements (McDonald & Deltenre, 1963)

Study of the Total Absorptance near 4.5 μ by Two Samples of N2O as Their Total Pressures and N2O Concentrations Were Independently Varied (Abesl & Shaw, 1963)

On the Atmospheric Infrared Continuum (Bignell et al. 1963)

Statistical Model Applied to the Region of the ν3 Fundamental of CO2 at 1200°K (Oppenheim & Ben-Aryeh, 1963)

A Weak Telluric Band of Carbon Dioxide (Diaz, 1963)

Predicting the Distribution of Infrared Radiation from the Clear Sky (Bennett & Bennett, 1962)

Infrared Spectrum of Hydrogen Fluoride: Line Positions and Line Shapes. Part II. Treatment of Data and Results (Herget et al. 1962)

Infrared Spectrum of Hydrogen Fluoride: Line Positions and Line Shapes. Part I. Experimental Details (Herndon et al. 1962)

Absorption Bands of Carbon Dioxide from 2.8–4.2 μ (Plyler et al. 1962)

Atmospheric Scattering Coefficients in the Visible and Infrared Regions (Knestrick et al. 1962)

Abundance of N2O in the Atmosphere (Rank et al. 1962)

Distribution of Irradiance in Haze and Fog (Eldridge & Johnson, 1962)

Spectral Radiance of Sky and Terrain at Wavelengths between 1 and 20 μ. III. Terrain Measurements (Eisner et al. 1962)

Transmission and Scattering Properties of a Nevada Desert Atmosphere under Cloudy Conditions (Gibbons et al. 1962)

Some Spectral Emissivities of Water Vapor in the 2.7-μ Region (Tourin, 1961)

Highly Precise Wavelengths in the Infrared. II. HCN, N2O, and CO (Rank et al. 1961)

Measurement of Atmospheric Transmissivity using Backscattered Light from a Pulsed Light Beam (Horman, 1961)

Transmission and Scattering Properties of a Nevada Desert Atmosphere (Gibbons et al. 1961)

Evaluation of Atmospheric Aerosol Particle Size Distribution from Scattering Measurements in the Visible and Infrared (Curcio, 1961)

Study of 1.4-μ, 1.9-μ, and 6.3-μ Water Vapor Bands at High Altitudes (Murcray et al. 1961)

Spectral Radiance of Sky and Terrain at Wavelengths between 1 and 20 Microns. II. Sky Measurements (Bell et al. 1960)

Infrared Solar Spectroscopy at the Jungfraujoch (Switzerland) (Delbouille & Migeotte, 1960)

Near Infrared Atmospheric Transmission to Solar Radiation (Gates, 1960)

Vibration-Rotation Bands of N2O (Tidwell et al. 1960)

Experimental Transmission Functions for the Pure Rotation Band of Water Vapor (Palmer, 1960)

Absorption by Infrared Bands of Carbon Dioxide Gas at Elevated Pressures and Temperatures (Edwards, 1960)

Atmospheric Absorptions in the Near Infrared at High Altitudes (Murcray et al. 1960)

Distribution of Infrared Radiance over a Clear Sky (Bennett et al. 1960)

Inference of Atmospheric Structure from Remote Radiation Measurements (Kaplan, 1959)

Experimental Technique for Studying Atmospheric Turbulence (Wolfe et al. 1959)

Spectral Emissivity of Carbon Dioxide from 1800–2500 cm−1 (Plass, 1959)

Abundance of Nitrous Oxide in Ground-Level Air (Birkeland & Shaw, 1959)

Solar Spectral Irradiance and Vertical Atmospheric Attenuation in the Visible and Ultraviolet (Dunkelman & Scolnik, 1959)

Far Infrared Spectra of H2O and H2S Taken with an Interferometric Spectrograph (Vanasse et al. 1959)

Wavelength Calibrations in Infrared. Part II. Use of Atomic Lines from a Hollow Cathode Discharge Tube with Neon as Carrier Gas (Rao et al. 1959)

Wavelength Calibrations in Infrared. Part I. Some Problems Concerning the Determination of Absolute Positions of Infrared Lines (Rao et al. 1959)

Pressure Modulation of Infrared Absorption.* II. Individual Lines in Vibration-Rotation Bands (Gilfert & Williams, 1959)

Temperature Dependence of the Rayleigh Scattering Coefficient in the Atmosphere (Deirmendjian, 1958)

Near Infrared Solar Radiation Measurements by Balloon to an Altitude of 100 000 Feet (Gates et al. 1958)

Pressure Modulation of Infrared Absorption.* I. Entire Vibration-Rotation Bands (Gilfert & Williams, 1958)

Correlation of Atmospheric Transmission with Backscattering (Curcio & Knestrick, 1958)

Diffuse Transmission through Real Atmospheres (Eldridge & Johnson, 1958)

Long Path Water Vapor Spectra with Pressure Broadening. II. 29 μ to 40 μ (Palmer, 1957)

Long Path Water Vapor Spectra with Pressure Broadening. I. 20 μ to 31.7 μ (Palmer, 1957)

Some Comments on Two Articles by Taylor and Yates (Birkeland et al. 1957)

Infrared Emission Spectra of the Atmosphere between 14.5 μ and 22.5 μ (Burch & Shaw, 1957)

Atmospheric Transmission in the Infrared (Taylor & Yates, 1957)

Infrared Evidence for Atmospheric Ozone at Sea Level (Taylor & Yates, 1956)

Spectral Diffuse Reflectance of Desert Surfaces (Ashburn & Weldon, 1956)

Atmospheric Turbidity and the Transmission of Ultraviolet Sunlight (Deirmendjian & Sekera, 1956)

Thermal Radiation from the Atmosphere (Sloan et al. 1956)

Infrared Transmission of Synthetic Atmospheres.* V. Absorption Laws for Overlapping Bands (Burch et al. 1956)

Infrared Evidence for the Presence of Ozone in the Lower Atmosphere (Burch, 1956)

Infrared Transmission of Synthetic Atmospheres.* IV. Application of Theoretical Band Models (Howard et al. 1956)

Infrared Transmission of Synthetic Atmospheres.* III. Absorption by Water Vapor (Howard et al. 1956)

Infrared Transmission of Synthetic Atmospheres.* II. Absorption by Carbon Dioxide (Howard et al. 1956)

Infrared Transmission of Synthetic Atmospheres.* I. Instrumentation (Howard et al. 1956)

Horizontal Atmospheric Transmittance Measurements with a Thallous Sulfide Cell Transmissometer (Pearson & Boettner, 1956)

Results of a Recent Attempt to Record the Solar Spectrum in the Region of 900–3000 A (Jursa et al. 1955)

Observations of Solar and Lunar Radiation at 1.5 Millimeters (Sinton, 1955)

Infrared Emission Spectrum of the Atmosphere (Sloan et al. 1955)

Horizontal Attenuation of Ultraviolet Light by the Lower Atmosphere (Baum & Dunkelman, 1955)

Infrared Absorption of Liquid Water from 2 to 42 Microns (Plyler & Acquista, 1954)

Measurements of Sky Luminance Distribution at Stockholm (Hopkinson, 1954)

Investigations of Atmospheric CO at the Jungfraujoch (Benesch et al. 1953)

The Infrared Spectra of Propylene and Propylene-d6 (Lord & Venkateswarlu, 1953)

Vibrational Spectra and Calculated Thermodynamic Properties of 1,1,1,2-Tetrachloroethane and Pentachloroethane (Nielsen et al. 1953)

The Forbidden Transition ν2 in the Infrared Spectrum of Methane (Burgess et al. 1953)

Absorption Line Width in the Infrared Spectrum of the Ammonia Molecule (Adel, 1953)

The Spectrum of Nitrogen Dioxide in the 1.4–3.4μ Region and the Vibrational and Rotational Constants of the NO2 Molecule (Moore, 1953)

Rotation-Vibration Spectra of Diatomic and Simple Polyatomic Molecules with Long Absorbing PathsXI. The Spectrum of Carbon Dioxide (Co2) below 1.25μ (Herzberg & Herzberg, 1953)

The Vertical Distribution of Nitrous Oxide and Methane in the Earth’s Atmosphere (Goldberg & Müller, 1953)

The Elimination of Atmospheric Water Vapor Absorption in the Perkin-Elmer Infrared Spectrometer (Fraser, 1953)

Fine Structure of the 2ν3 Band of Methane (Rank et al. 1953)

Atmospheric Attenuation at Khartoum, Sudan (Beck et al. 1953)

An Experimental Study of Atmospheric Transmission (Curcio et al. 1953)

Near-Infrared Absorption by Entire Bands of Carbon Dioxide (Howard & Chapman, 1952)

The Influence of Field of View on Measurements of Atmospheric Transmission (Stewart & Curcio, 1952)

A Method for the Determination of Atmospheric Transmission Functions from Laboratory Absorption Measurements (Plass, 1952)

The Luminous Directional Reflectance of Snow (Middleton & Mungall, 1952)

The Pressure Dependence of the Absorption by Entire Bands of Water Vapor in the Near Infrared (Howard & Chapman, 1952)

Measurements of the Brightness of the Twilight Sky (Koomen et al. 1952)

Refractive Indices of Water Vapor and Carbon Dioxide at Low Pressure (Newbound, 1949)

Night Sky Brightness Measurements in Latitudes below 45° (Hulburt, 1949)

Elimination of Water Vapor in Infra-Red Spectrometers (Giguère & Badger, 1948)

An Estimate of Transparency of the Atmospheric Window 16 Mu to 24 Mu (Adel, 1947)

The Upper Atmosphere of the Earth (Hulburt, 1947)

Brightness and Polarization of the Daylight Sky at Various Altitudes above Sea Level (Tousey & Hulburt, 1947)

A Spectrophotometer for the Determination of the Water Vapor in a Vertical Column of the Atmosphere (Foster & Foskett, 1945)

The Determination of the Concentration of Benzene and Toluene in Air by a Spectroscopic Method (Cole, 1942)

The “Diffusing Effect” of Fog (Middleton, 1942)

Optics of Atmospheric Haze (Hulburt, 1941)

The Distribution of Energy in the Visible Spectrum of Daylight (Taylor & Kerr, 1941)

The Transmission of Infra-Red Light by Fog (Sanderson, 1940)

Transmission of Infra-Red Radiation Through Fog (Smith & Hayes, 1940)

An Estimate of the Absorption of Air in the Extreme Ultraviolet (Schneider, 1940)

Laboratory Analysis of the Selective Absorption of Light by Sea Water (Clarke & James, 1939)

The Brightness of the Twilight Sky and the Density and Temperature of the Atmosphere (Hulburt, 1938)

The Reflection and Absorption of Daylight at the Surface of the Ocean (Powell & Clarke, 1936)

A Photoelectric Method of Measuring the Transparency of the Lower Atmosphere (Byram, 1935)

Visibility Photometers for Measuring Atmospheric Transparency (Byram, 1935)

Light Absorption and Distribution of Atmospheric Ozone1,2 (Ladenburg, 1935)

Light Absorption in the Atmosphere and Its Photochemistry (Wulf, 1935)

Attenuation of Light in the Lower Atmosphere (Hulburt, 1935)

The Penetration of the Red, Green and Violet Components of Daylight into Atlantic Waters (Oster & Clarke, 1935)

Absorption of Light by Sea Water (Stephenson, 1934)

The Absorption of Ultraviolet and Visible Light by Water (Dawson & Hulburt, 1934)

Intensity and Spectral Distribution of Solar Radiation in New Orleans (Laurens & Mayerson, 1933)

The Ultraviolet Transmission Coefficient of the Earth’s Atmosphere (Rockwood & Sawyer, 1932)

On the Penetration of Daylight into the Sea (Hulburt, 1932)

The Zinc Sulphide Method of Measuring Ultraviolet Radiation and the Results of Three Years’ Observations on Baltimore Sunshine (Clark, 1931)

Ultraviolet Radiation from the Sun and Heated Tungsten (Forsythe & Christison, 1930)

A Comparison of Laboratory and Solar Wave Lengths (Burns, 1930)

On the Efficient Utilization of Solar Energy (Goddard, 1929)

Spectral Reflectances of Common Materials in the Ultraviolet Region (Luckiesh, 1929)

The Ultraviolet, Visible and Infrared Reflectivities of Snow, Sand and Other Substances (Hulburt, 1928)

The Infrared Absorption Spectra of Acetylene, Ethylene and Ethane (Levin & Meyer, 1928)

The Near Infrared Absorption Spectra of Liquid Benzene and Toluene (Barnes & Fulweiler, 1927)

On the Infrared Absorption Spectra of Several Gases (Meyer et al. 1927)

Solarimeters and Solarigraphs Simple Instruments for Direct Readings of Solar Radiation Intensity from Sun and Sky (Gorczyński, 1927)

Atmospheric Absorption and Transmission in Searchlight Practice (Langer, 1926)

Meteorological Instruments and Apparatus Employed by the United States Weather Bureau (Covert, 1925)

On a Simple Method of Recording the Total and Partial Intensities of Solar Radiation (Gorczyński, 1924)

The Infrared Absorption Spectrum of Carbon Monoxide (Lowry, 1924)

The Effect of the Diffusion and Absorption by the Atmosphere on Signal Lights and Projectors (Karrer, 1923)

Recent Measurements of Stellar and Planetary Radiation (Coblentz, 1922)

The Measurement of Solar, Sky, Nocturnal and Stellar Radiation (Coblentz, 1921)

Posted in Climate science | Leave a Comment »

New research – cryosphere (October 11, 2016)

Posted by Ari Jokimäki on October 11, 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.


Grounding line retreat of Pope, Smith, and Kohler Glaciers, West Antarctica, measured with Sentinel-1a radar interferometry data (Scheuchl et al. 2016)

Abstract: We employ Sentinel-1a C band satellite radar interferometry data in Terrain Observation with Progressive Scans mode to map the grounding line and ice velocity of Pope, Smith, and Kohler glaciers, in West Antarctica, for the years 2014–2016 and compare the results with those obtained using Earth Remote Sensing Satellites (ERS-1/2) in 1992, 1996, and 2011. We observe an ongoing, rapid grounding line retreat of Smith at 2 km/yr (40 km since 1996), an 11 km retreat of Pope (0.5 km/yr), and a 2 km readvance of Kohler since 2011. The variability in glacier retreat is consistent with the distribution of basal slopes, i.e., fast along retrograde beds and slow along prograde beds. We find that several pinning points holding Dotson and Crosson ice shelves disappeared since 1996 due to ice shelf thinning, which signal the ongoing weakening of these ice shelves. Overall, the results indicate that ice shelf and glacier retreat in this sector remain unabated.

On the recent contribution of the Greenland ice sheet to sea level change (van den Broeke et al. 2016)

Abstract: We assess the recent contribution of the Greenland ice sheet (GrIS) to sea level change. We use the mass budget method, which quantifies ice sheet mass balance (MB) as the difference between surface mass balance (SMB) and solid ice discharge across the grounding line (D). A comparison with independent gravity change observations from GRACE shows good agreement for the overlapping period 2002–2015, giving confidence in the partitioning of recent GrIS mass changes. The estimated 1995 value of D and the 1958–1995 average value of SMB are similar at 411 and 418 Gt yr−1, respectively, suggesting that ice flow in the mid-1990s was well adjusted to the average annual mass input, reminiscent of an ice sheet in approximate balance. Starting in the early to mid-1990s, SMB decreased while D increased, leading to quasi-persistent negative MB. About 60 % of the associated mass loss since 1991 is caused by changes in SMB and the remainder by D. The decrease in SMB is fully driven by an increase in surface melt and subsequent meltwater runoff, which is slightly compensated by a small (< 3 %) increase in snowfall. The excess runoff originates from low-lying (< 2000 m a.s.l.) parts of the ice sheet; higher up, increased refreezing prevents runoff of meltwater from occurring, at the expense of increased firn temperatures and depleted pore space. With a 1991–2015 average annual mass loss of ~ 0.47 ± 0.23 mm sea level equivalent (SLE) and a peak contribution of 1.2 mm SLE in 2012, the GrIS has recently become a major source of global mean sea level rise.

Tropical Pacific SST drivers of recent Antarctic sea ice trends (Purich et al. 2016)

Abstract: A strengthening of the Amundsen Sea Low from 1979-2013 has been shown to largely explain the observed increase in Antarctic sea ice concentration in the eastern Ross Sea and decrease in the Bellingshausen Sea. Here we show that while these changes are not generally seen in freely-running coupled climate model simulations, they are reproduced in simulations of two independent coupled climate models; one constrained by observed sea surface temperature anomalies in the tropical Pacific, and the other by observed surface wind-stress in the tropics. Our analysis confirms previous results and strengthens the conclusion that the phase change in the Interdecadal Pacific Oscillation from positive to negative over 1979-2013 contributed to the observed strengthening of the Amundsen Sea Low and associated pattern of Antarctic sea ice change during this period. New support for this conclusion is provided by simulated trends in spatial patterns of sea ice concentrations that are similar to those observed. Our results highlight the importance of accounting for teleconnections from low to high latitudes in both model simulations and observations of Antarctic sea ice variability and change.

Quantifying ice loss in the eastern Himalayas since 1974 using declassified spy satellite imagery (Maurer et al. 2016)

Abstract: Himalayan glaciers are important natural resources and climate indicators for densely populated regions in Asia. Remote sensing methods are vital for evaluating glacier response to changing climate over the vast and rugged Himalayan region, yet many platforms capable of glacier mass balance quantification are somewhat temporally limited due to typical glacier response times. We here rely on declassified spy satellite imagery and ASTER data to quantify surface lowering, ice volume change, and geodetic mass balance during 1974–2006 for glaciers in the eastern Himalayas, centered on the Bhutan–China border. The wide range of glacier types allows for the first mass balance comparison between clean, debris, and lake-terminating (calving) glaciers in the region. Measured glaciers show significant ice loss, with an estimated mean annual geodetic mass balance of −0.13 ± 0.06 m w.e. yr−1 (meters of water equivalent per year) for 10 clean-ice glaciers, −0.19 ± 0.11 m w.e. yr−1 for 5 debris-covered glaciers, −0.28 ± 0.10 m w.e. yr−1 for 6 calving glaciers, and −0.17±0.05 m w.e. yr−1 for all glaciers combined. Contrasting hypsometries along with melt pond, ice cliff, and englacial conduit mechanisms result in statistically similar mass balance values for both clean-ice and debris-covered glacier groups. Calving glaciers comprise 18 % (66 km2) of the glacierized area yet have contributed 30 % (−0.7 km3) to the total ice volume loss, highlighting the growing relevance of proglacial lake formation and associated calving for the future ice mass budget of the Himalayas as the number and size of glacial lakes increase.

Quantifying the uncertainty in historical and future simulations of Northern Hemisphere spring snow cover (Thackeray et al. 2016)

Abstract: Projections of 21st century Northern Hemisphere (NH) spring snow cover extent (SCE) from two climate model ensembles are analyzed to characterize their uncertainty. The Fifth Coupled Model Intercomparison Project (CMIP5) multi-model ensemble exhibits variability due to both model differences and internal climate variability, whereas spread generated from a Canadian Earth System Model large ensemble (CanESM-LE) experiment is solely due to internal variability. The analysis shows that simulated 1981-2010 spring SCE trends are slightly weaker than observed (using an ensemble of snow products). Spring SCE is projected to decrease by -3.7±1.1% decade-1 within the CMIP5 ensemble over the 21st century. SCE loss is projected to accelerate for all spring months over the 21st century, with the exception of June (because most snow in this month has melted by the latter half of the 21st century). For 30-year spring SCE trends over the 21st century, internal variability estimated from CanESM-LE is substantial, but smaller than inter-model spread from CMIP5. Additionally, internal variability in NH extratropical land warming trends can affect SCE trends in the near-future (R2 = 0.45), while variability in winter precipitation can also have a significant (but lesser) impact on SCE trends. On the other hand, a majority of the inter-model spread is driven by differences in simulated warming (dominant in March, April, May), and snow cover available for melt (dominant in June). The strong temperature/SCE linkage suggests that model uncertainty in projections of SCE could be potentially reduced through improved simulation of spring season warming over land.

Other papers

Persistent artifacts in the NSIDC ice motion dataset and their implications for analysis (Szanyi et al. 2016)

Distributed ice thickness and glacier volume in southern South America (Carrivick et al. 2016)

Century-scale perspectives on observed and simulated Southern Ocean sea ice trends from proxy reconstructions (Hobbs et al. 2016)

Identifying dynamically induced variability in glacier mass-balance records (Christian et al. 2016)

Impacts of marine instability across the East Antarctic Ice Sheet on Southern Ocean dynamics (Phipps et al. 2016)

Effects of bryophyte and lichen cover on permafrost soil temperature at large scale (Porada et al. 2016)

Meltwater Pathways from Marine Terminating Glaciers of the Greenland Ice Sheet (Gillard et al. 2016)

Assimilation of surface velocities between 1996 and 2010 to constrain the form of the basal friction law under Pine Island Glacier (Gillet-Chaulet et al. 2016)

Linked trends in the south Pacific sea ice edge and Southern Oscillation Index (Kwok et al. 2016)

Greenland during the last interglacial: the relative importance of insolation and oceanic changes (Pedersen et al. 2016)

The impact of melt ponds on summertime microwave brightness temperatures and sea-ice concentrations (Kern et al. 2016)

The EUMETSAT sea ice concentration climate data record (Tonboe et al. 2016)

Temperature reconstruction from the length fluctuations of small glaciers in the eastern Alps (northeastern Italy) (Zecchetto et al. 2016)

Variability, trends, and predictability of seasonal sea ice retreat and advance in the Chukchi Sea (Serreze et al. 2016)

Producing cloud-free MODIS snow cover products with conditional probability interpolation and meteorological data (Dong & Menzel, 2016)

ICESat laser altimetry over small mountain glaciers (Treichler & Kääb, 2016)

Heterogeneous glacier thinning patterns over the last 40 years in Langtang Himal, Nepal (Ragettli et al. 2016)

Arctic sea ice patterns driven by the Asian Summer Monsoon (Grunseich & Wang, 2016)

Impact of climate warming on snow processes in ny-Ålesund, a polar maritime site at Svalbard (López-Moreno et al. 2016)

Variations in ice velocities of Pine Island Glacier Ice Shelf evaluated using multispectral image matching of Landsat time series data (Han et al. 2016)

Application of GRACE to the assessment of model-based estimates of monthly Greenland Ice Sheet mass balance (2003–2012) (Schlegel et al. 2016)

Near-real-time Arctic sea ice thickness and volume from CryoSat-2 (Tilling et al. 2016)

Potential for estimation of snow depth on Arctic sea ice from CryoSat-2 and SARAL/AltiKa missions (Guerreiro et al. 2016)

Sliding of temperate basal ice on a rough, hard bed: creep mechanisms, pressure melting, and implications for ice streaming (Krabbendam, 2016)

Monte Carlo modelling projects the loss of most land-terminating glaciers on Svalbard in the 21st century under RCP 8.5 forcing (Möller et al. 2016)

North-east sector of the Greenland Ice Sheet to undergo the greatest inland expansion of supraglacial lakes during the 21st century (Ignéczi et al. 2016)

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

New research – hydrosphere (September 26, 2016)

Posted by Ari Jokimäki on September 26, 2016

Some of the latest papers on climate change impacts on hydrosphere 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.


Ocean acidification over the next three centuries using a simple global climate carbon-cycle model: projections and sensitivities (Hartin et al. 2016)

Abstract: Continued oceanic uptake of anthropogenic CO2 is projected to significantly alter the chemistry of the upper oceans over the next three centuries, with potentially serious consequences for marine ecosystems. Relatively few models have the capability to make projections of ocean acidification, limiting our ability to assess the impacts and probabilities of ocean changes. In this study we examine the ability of Hector v1.1, a reduced-form global model, to project changes in the upper ocean carbonate system over the next three centuries, and quantify the model’s sensitivity to parametric inputs. Hector is run under prescribed emission pathways from the Representative Concentration Pathways (RCPs) and compared to both observations and a suite of Coupled Model Intercomparison (CMIP5) model outputs. Current observations confirm that ocean acidification is already taking place, and CMIP5 models project significant changes occurring to 2300. Hector is consistent with the observational record within both the high- (> 55°) and low-latitude oceans (< 55°). The model projects low-latitude surface ocean pH to decrease from preindustrial levels of 8.17 to 7.77 in 2100, and to 7.50 in 2300; aragonite saturation levels (ΩAr) decrease from 4.1 units to 2.2 in 2100 and 1.4 in 2300 under RCP 8.5. These magnitudes and trends of ocean acidification within Hector are largely consistent with the CMIP5 model outputs, although we identify some small biases within Hector’s carbonate system. Of the parameters tested, changes in [H+] are most sensitive to parameters that directly affect atmospheric CO2 concentrations – Q10 (terrestrial respiration temperature response) as well as changes in ocean circulation, while changes in ΩAr saturation levels are sensitive to changes in ocean salinity and Q10. We conclude that Hector is a robust tool well suited for rapid ocean acidification projections and sensitivity analyses, and it is capable of emulating both current observations and large-scale climate models under multiple emission pathways.

Anthropogenic and climate-driven water depletion in Asia (Yi et al. 2016)

Abstract: Anthropogenic depletion of terrestrial water storage (TWS) can be alleviated in wet years and intensified in dry years, and this wet/dry pattern spanning seasons to years is termed climate variability. However, the anthropogenic and climate-driven changes have not been isolated in previous studies; thus, the estimated trend of changes in TWS is strongly dependent on the study period. Here we try to remove the influence of climate variability from the estimation of the anthropogenic contribution, which is an indicator of the environmental burden and important for TWS projections. Toward this end, we propose a linear relationship between the variation in water storage and precipitation. Factors related to the sensitivity of water storage to precipitation are given to correct for the climate variability, and the anthropogenic depletion of terrestrial water and groundwater in Asia is estimated to be −187 ± 38 Gt/yr and −100 ± 47 Gt/yr, respectively.

Are long tide gauge records in the wrong place to measure global mean sea level rise? (Thompson et al. 2016)

Abstract: Ocean dynamics, land motion, and changes in Earth’s gravitational and rotational fields cause local sea level change to deviate from the rate of global mean sea level rise. Here, we use observations and simulations of spatial structure in sea level change to estimate the likelihood that these processes cause sea level trends in the longest and highest-quality tide gauge records to be systematically biased relative to the true global mean rate. The analyzed records have an average 20th century rate of approximately 1.6 mm/yr, but based on the locations of these gauges, we show the simple average underestimates the 20th century global mean rate by 0.1  ±  0.2 mm/yr. Given the distribution of potential sampling biases, we find < 1% probability that observed trends from the longest and highest-quality TG records are consistent with global mean rates less than 1.4 mm/yr.

Development of a 0.5 deg global monthly raining day product from 1901-2010 (Stillman & Zeng, 2016)

Abstract: While several long-term global datasets of monthly precipitation amount (P) are widely available, only the Climate Research Unit (CRU) provides long-term global monthly raining day number (N) data (i.e., daily precipitation frequency in a month), with P/N representing the daily precipitation intensity. However, because CRU N is based on a limited number of gauges, it is found to perform poorly over data sparse regions. By combining the CRU method with a short-term gauge-satellite merged global daily precipitation dataset (CMORPH) and a global long-term monthly precipitation dataset (GPCC) with far more gauges than used in CRU, a new 0.5 deg global N dataset from 1901-2010 is developed, which differs significantly from CRU N. Compared with three independent regional daily precipitation products over U.S., China, and South America based on much denser gauge networks than used in CRU, the new product shows significant improvement over CRU N.

Detection and delineation of glacial lakes and identification of potentially dangerous lakes of Dhauliganga basin in the Himalaya by remote sensing techniques (Jha & Khare, 2016)

Abstract: Glaciers are retreating and thinning in the high altitude of the Himalayas due to global warming, causing into formation of numerous glacial lakes. It is necessary to monitor these glacial lakes consistently to save properties and lives downstream from probable disastrous glacial lake outburst flood. In this study, image processing software ArcGIS and ERDAS Imagine have been used to analyse multispectral image obtained by Earth resource satellite Landsat for delineating the glacial lakes with the help of image enhancement technique like NDWI. Landsat data since 1972 through 2013 have been used and maximum seven glacial lakes (L1–L7) have been detected and delineated in Dhauliganga catchment, they are situated above 4000 masl. The Glacial Lake L2 (Lat 30°26′45″E and Long 80°23′16″N) is the largest whose surface area was 132,300 m2 in Sept 2009, and L6 (Lat 30°23′27″E and Long 80°31′52″N) is highly unstable with variation rate −55 to +145 % with increasing trend. Additionally, glacial lakes L2 (Lat 30°26′45″E and Long 80°23′16″N) and L6 (Lat 30°23′27″E and Long 80°31′52″N) have been identified as potentially hazardous. These lakes may probably burst; as a result, huge reserve of water and debris may be released all on a sudden. This may transform into hazardous flash flood in downstream causing loss of lives, as well as the destruction of houses, bridges, fields, forests, hydropower stations, roads, etc. It is to note that Dhauliganga river considered in this study is a tributary of Kaliganga river, and should not be confused with its namesake the Dhauliganga river, which is a tributary of Alaknanda river.

Other papers

Extreme hydrological changes in the southwestern US drive reductions in water supply to Southern California by mid century (Pagán et al. 2016)

Regionalizing Africa: Patterns of Precipitation Variability in Observations and Global Climate Models (Badr et al. 2016)

Evidencing decadal and interdecadal hydroclimatic variability over the Central Andes (Segura et al. 2016)

The uncertainties and causes of the recent changes in global evapotranspiration from 1982 to 2010 (Dong & Dai, 2016)

Spatial pattern of reference evapotranspiration change and its temporal evolution over Southwest China (Sun et al. 2016)

Climate change in the Blue Nile Basin Ethiopia: implications for water resources and sediment transport (Wagena et al. 2016)

Rainfall in Qatar: Is it changing? (Mamoon & Rahman, 2016)

Global Precipitation Measurement (GPM) Mission Products and Services at the NASA Goddard Earth Sciences (GES) Data and Information Services Center (DISC) (Liu et al. 2016)

A multi-satellite climatology of clouds, radiation and precipitation in southern West Africa and comparison to climate models (Hill et al. 2016)

Detection, Attribution and Projection of Regional Rainfall Changes on (Multi-) Decadal Time Scales: A Focus on Southeastern South America (Zhang et al. 2016)

Which weather systems are projected to cause future changes in mean and extreme precipitation in CMIP5 simulations? (Utsumi et al. 2016)

Out-phased decadal precipitation regime shift in China and the United States (Yang & Fu, 2016)

Forcing of recent decadal variability in the Equatorial and North Indian Ocean (Thompson et al. 2016)

Proxy-based reconstruction of surface water acidification and carbonate saturation of the Levant Sea during the Anthropocene (Bialik & Sisma-Ventura, 2016)

Understanding decreases in land relative humidity with global warming: conceptual model and GCM simulations (Byrne & O’Gorman, 2016)

Spatial trend analysis of Hawaiian rainfall from 1920 to 2012 (Frazier & Giambelluca, 2016)

Mapping of West Siberian taiga wetland complexes using Landsat imagery: implications for methane emissions (Terentieva et al. 2016)

Wind driven mixing at intermediate depths in an ice-free Arctic Ocean (Lincoln et al. 2016)

Seasonal Evolution of Supraglacial Lakes on an East Antarctic Outlet Glacier (Langley et al. 2016)

Temperature-salinity structure of the North Atlantic circulation and associated heat and freshwater transports (Xu et al. 2016)

Eustatic and Relative Sea Level Changes (Rovere et al. 2016)

A mechanism for the response of the zonally asymmetric subtropical hydrologic cycle to global warming (Levine & Boos, 2016)

Quantifying the contribution of glacier-melt water in the expansion of the largest lake in Tibet (Tong et al. 2016)

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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.


The Effects of Ocean Heat Uptake on Transient Climate Sensitivity (Rose & Rayborn, 2016)

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)

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)

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)

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)

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)

Understanding the varied influence of mid-latitude jet position on clouds and cloud-radiative effects in observations and global climate models (Grise & Medeiros, 2016)

Effect of land cover change on snow free surface albedo across the continental United States (Wickham et al. 2016)

Forced response and internal variability of summer climate over western North America (Kamae et al. 2016)

Detection and attribution of climate change at regional scale: case study of Karkheh river basin in the west of Iran (Zohrabi et al. 2016)

Atmospheric lifetimes, infrared absorption spectra, radiative forcings and global warming potentials of NF3 and CF3CF2Cl (CFC-115) (Totterdill et al. 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)

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)

Effects of 20–100 nm particles on liquid clouds in the clean summertime Arctic (Leaitch et al. 2016)

Assessment of the first indirect radiative effect of ammonium-sulfate-nitrate aerosols in East Asia (Han et al. 2016)

Sensitivity of precipitation extremes to radiative forcing of greenhouse gases and aerosols (Lin et al. 2016)

Global climate forcing of aerosols embodied in international trade (Lin et al. 2016)

Reprocessing of HIRS Satellite Measurements from 1980-2015: Development Towards a Consistent Decadal Cloud Record (Menzel et al. 2016)

Radiative Forcing from Anthropogenic Sulfur and Organic Emissions Reaching the Stratosphere (Yu et al. 2016)

Near miss: the importance of the natural atmospheric CO2 concentration to human historical evolution (Archer, 2016)

Long-Term Variations of Noctilucent Clouds at ALOMAR (Fiedler et al. 2016)

Estimating Arctic sea-ice shortwave albedo from MODIS data (Qu et al. 2016)

Surface albedo raise in the South American Chaco: Combined effects of deforestation and agricultural changes (Houspanossian et al. 2016)

New Observational Evidence for a Positive Cloud Feedback that Amplifies the Atlantic Multidecadal Oscillation (Bellomo et al. 2016)

Surface water and heat exchange comparison between alpine meadow and bare land in a permafrost region of the Tibetan Plateau (You et al. 2016)

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)

Comparison of Methods: Attributing the 2014 record European temperatures to human influences (Uhe et al. 2016)

Relevance of long term time – series of atmospheric parameters at a mountain observatory to models for climate change (Kancírová et al. 2016)

An energy balance perspective on regional CO2-induced temperature changes in CMIP5 models (Räisänen, 2016)

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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.


A global catalogue of large SO2 sources and emissions derived from the Ozone Monitoring Instrument (Fioletov et al. 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)

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)

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)

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)

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)

Long-term visibility variation in Athens (1931–2013): a proxy for local and regional atmospheric aerosol loads (Founda et al. 2016)

Particulate air pollution from wildfires in the Western US under climate change (Liu et al. 2016)

Climate-driven ground-level ozone extreme in the fall over the Southeast United States (Zhang et al. 2016)

Radon as a tracer of atmospheric influences on traffic-related air pollution in a small inland city (Williams et al. 2016)

Bioaerosols in the Earth system: Climate, health, and ecosystem interactions (Fröhlich-Nowoisky et al. 2016)

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)

Estimating Minimum Detection Times for Satellite Remote Sensing of Trends in Mean and Extreme Precipitable Water Vapor (Roman et al. 2016)

A comprehensive estimate for loss of atmospheric carbon tetrachloride (CCl4) to the ocean (Butler et al. 2016)

Significant increase of summertime ozone at Mount Tai in Central Eastern China (Sun et al. 2016)

Snow Covered Soils Produce N2O that is Lost from Forested Catchments (Enanga et al. 2016)

Spatial and temporal variability of urban fluxes of methane, carbon monoxide and carbon dioxide above London, UK (Helfter et al. 2016)

Climatic variability of the column ozone over the Iranian plateau (Mousavi et al. 2016)

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)

The natural oscillations in stratospheric ozone observed by the GROMOS microwave radiometer at the NDACC station Bern (Moreira et al. 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)

Relationship of ground-level ozone with synoptic weather conditions in Chicago (Jing et al. 2016)

Global detection of absorbing aerosols over the ocean in the red and near infrared spectral region (Waquet et al. 2016)

Atmospheric benzene observations from oil and gas production in the Denver Julesburg basin in July and August 2014 (Halliday et al. 2016)

Carbon monoxide climatology derived from the trajectory mapping of global MOZAIC-IAGOS data (Osman et al. 2016)

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

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.


Methane emissions proportional to permafrost carbon thawed in Arctic lakes since the 1950s (Anthony et al. 2016)

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)

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)

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)

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)

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)

Airborne methane remote measurements reveal heavy-tail flux distribution in Four Corners region (Frankenberg et al. 2016)

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)

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)

Vegetation carbon sequestration in Chinese forests from 2010 to 2050 (He et al. 2016)

CH4 concentrations over the Amazon from GOSAT consistent with in situ vertical profile data (Webb et al. 2016)

CH4 exchanges of the natural ecosystems in China during the past three decades: the role of wetland extent and its dynamics (Wei & Wang, 2016)

Mesoscale modulation of air-sea CO2 flux in Drake Passage (Song et al. 2016)

Biomass turnover time in terrestrial ecosystems halved by land use (Erb et al. 2016)

Permafrost carbon as a missing link to explain CO 2 changes during the last deglaciation (Crichton et al. 2016)

High export via small particles before the onset of the North Atlantic spring bloom (Giering et al. 2016)

Inorganic carbon cycling and biogeochemical processes in an Arctic inland sea (Hudson Bay) (Burt et al. 2016)

Constrained partitioning of autotrophic and heterotrophic respiration reduces model uncertainties of forest ecosystem carbon fluxes but not stocks (Carbone et al. 2016)

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)

Apparent winter CO2 uptake by a boreal forest due to decoupling (Jocher et al. 2016)

Over-estimating climate warming-induced methane gas escape from the seafloor by neglecting multi-phase flow dynamics (Stranne et al. 2016)

Strong regional atmospheric 14C signature of respired CO2 observed from a tall tower over the mid-western United States (LaFranchi et al. 2016)

Underestimation of boreal soil carbon stocks by mathematical soil carbon models linked to soil nutrient status (Ťupek et al. 2016)

Methane Emissions from global rice fields: Magnitude, spatio-temporal patterns and environmental controls (Zhang et al. 2016)

Modeling pCO2 variability in the Gulf of Mexico (Xue et al. 2016)

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

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.


High-income does not protect against hurricane losses (Geiger et al. 2016)

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)

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)

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)

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)

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)

Increased drought and pluvial risk over California due to changing oceanic conditions (Kam & Sheffield, 2016)

Comparing hurricane and extratropical storm surge for the Mid-Atlantic and Northeast Coast of the United States for 1979–2013 (Booth et al. 2016)

Storm track processes and the opposing influences of climate change (Shaw et al. 2016)

Can reanalysis datasets describe the persistent temperature and precipitation extremes over China? (Zhu et al. 2016)

Exceptionally extreme drought in Madeira Archipelago in 2012: Vegetation impacts and driving conditions (Liberato et al. 2016)

An independent assessment of anthropogenic attribution statements for recent extreme temperature and rainfall events (Angélil et al. 2016)

Future hurricane storm surge risk for the U.S. gulf and Florida coasts based on projections of thermodynamic potential intensity (Balaguru et al. 2016)

Evaluation of downscaled wind speeds and parameterised gusts for recent and historical windstorms in Switzerland (Stucki et al. 2016)

The Record-Breaking 2015 Hurricane Season in the eastern North Pacific: An Analysis of Environmental Conditions (Collins et al. 2016)

Centennial drought outlook over the CONUS using NASA-NEX downscaled climate ensemble (Ahmadalipour et al. 2016)

Compounding factors causing the unusual absence of tropical cyclones in the western North Pacific during August 2014 (Hong et al. 2016)

Synoptic climatology of the early 21st century drought in the Colorado River Basin and relationships to reservoir water levels (Kirk et al. 2016)

The challenge of accurately quantifying future megadrought risk in the American Southwest (Coats & Mankin, 2016)

Will Global Warming Make Hurricane Forecasting More Difficult? (Emanuel, 2016)

A comparison of heat wave climatologies and trends in China based on multiple definitions (You et al. 2016)

Diagnosing United States hurricane landfall risk: An alternative to count-based methodologies (Staehling & Truchelut, 2016)

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)

Distinct weekly cycles of thunderstorms and a potential connection with aerosol type in China (Yang et al. 2016)

Trends and variability in droughts in the Pacific Islands and northeast Australia (McGree et al. 2016)

Spatial and temporal variations of blowing dust events in the Taklimakan Desert (Yang et al. 2016)

My Drought is Different from Your Drought: A Case Study of the Policy Implications of Multiple Ways of Knowing Drought (Kohl & Knox, 2016)

Selected physical parameters as determinants of flood fatalities in Bangladesh, 1972–2013 (Paul et al. 2016)

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

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.


Observed and simulated full-depth ocean heat-content changes for 1970–2005 (Cheng et al. 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)

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)

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)

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)

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)

First ground-based observations of mesopause temperatures above the Eastern-Mediterranean Part I: Multi-day oscillations and tides (Silber et al. 2016)

An enhanced single-channel algorithm for retrieving land surface temperature from Landsat series data (Wang et al. 2016)

Observed changes of temperature extremes in Serbia over the period 1961 − 2010 (Ruml et al. 2016)

The inter-annual variations and the long-term trends of monthly air temperatures in Iraq over the period 1941–2013 (Muslih & Błażejczyk, 2016)

A multiregion model evaluation and attribution study of historical changes in the area affected by temperature and precipitation extremes (Dittus et al. 2016)

Changes in wind speed under heat waves enhance urban heat islands in Beijing metropolitan area (Li et al. 2016)

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)

Confidence intervals for time averages in the presence of long range correlations, a case study on earth surface temperature anomalies (Massah & Kantz, 2016)

An ensemble of ocean reanalyses for 1815–2013 with sparse observational input (Giese et al. 2016)

Arctic-North Pacific coupled impacts on the late autumn cold in North America (Sung et al. 2016)

Wet-bulb, dew point, and air temperature trends in Spain (Moratiel et al. 2016)

Insights into elevation-dependent warming in the Tibetan Plateau-Himalayas from CMIP5 model simulations (Palazzi et al. 2016)

Spatial variations in temperature in a mountainous region of Jeju Island, South Korea (Um & Kim, 2016)

Gap filling and homogenization of climatological datasets in the headwater region of the Upper Blue Nile Basin, Ethiopia (Woldesenbet et al. 2016)

A homogenized long-term temperature record for the Western Cape Province in South Africa: 1916–2013 (Lakhraj-Govender et al. 2016)

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)

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)

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)

Recent seasonal and long-term changes in southern Australian frost occurrence (Crimp et al. 2016)

Surface temperature trends from homogenized time series in South Africa: 1931–2015 (Kruger & Nxumalo, 2016)

Investigations of the middle atmospheric thermal structure and oscillations over sub-tropical regions in the Northern and Southern Hemispheres (Sharma et al. 2016)

Recent amplification of the North American winter temperature dipole (Singh et al. 2016)

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)

Spatial distribution of temperature trends and extremes over Maharashtra and Karnataka States of India (Dhorde et al. 2016)

Assessing atmospheric temperature data sets for climate studies (Cederlöf et al. 2016)

Ocean heat uptake and interbasin transport of passive and redistributive surface heating (Garuba & Klinger, 2016)

Temperature and precipitation regional climate series over the central Pyrenees during 1910–2013 (Pérez-Zanón et al. 2016)

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