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Archive for July, 2012

New research from last week 27-30

Posted by Ari Jokimäki on July 30, 2012

New research from last week was in boreal summer break for 4 weeks. Surprisingly journals kept pushing out papers. Here are some papers that I noted during the break. Links are to abstracts only, so you have to hunt down the full texts yourself when needed.

Arctic Clouds and Surface Radiation: Arctic Clouds and Surface Radiation – a critical comparison of satellite retrievals and the ERA-Interim reanalysis – Zygmuntowska et al. (2012)

Permafrost distribution in the European Alps: Permafrost distribution in the European Alps: calculation and evaluation of an index map and summary statistics – Boeckli et al. (2012)

Small part of Arctic sea ice extent decline has been due to Atlantic Multidecadal Oscillation: Sources of multi-decadal variability in Arctic sea ice extent – Day et al. (2012)

The effect of climate change and ocean acidification on seagrasses and marine macroalgae: Climate Change and Ocean AcidificationEffects on Seagrasses and Marine Macroalgae – Koch et al. (2012)

How vegetation in Switzerland responded to rapid warming in the past?: Vegetation responses to rapid warming and to minor climatic fluctuations during the Late-Glacial Interstadial (GI-1) at Gerzensee (Switzerland) – Ammann et al. (2012)

Anthropogenic aerosols may have masked greenhouse gas-induced changes in rainfall over north-western Australia: Aerosol- and greenhouse gas-induced changes in summer rainfall and circulation in the Australasian region: a study using single-forcing climate simulations – Rotstayn et al. (2012)

Evidence for possible similarities between End-Permian mass extinction and expected 21st century situation: Evidence for end-Permian ocean acidification from calcium isotopes in biogenic apatite – Hinojosa et al. (2012)

Analysis of global tropical cyclone activity over the past 5,000 years: Punctuated global tropical cyclone activity over the past 5,000 years – Nott & Forsyth (2012)

Reconstructing the sea ice season length: Variability in the length of the sea ice season in the Middle Eocene Arctic – Stickley et al. (2012)

Western Mediterranean precipitation over the last 300 years from instrumental observations: Western Mediterranean precipitation over the last 300 years from instrumental observations – Camuffo et al. (2012)

Most genetically diverse lizard populations are the ones most at risk from climate change: Predicting the impacts of climate change on genetic diversity in an endangered lizard species – Dubey et al. (2012)

CO2 lagged temperature by less than 400 years and even short lead is possible during last deglaciation: Tightened constraints on the time-lag between Antarctic temperature and CO2 during the last deglaciation – Pedro et al. (2012)

Significant increase in atmospheric long-wave radiation in Israel is caused by water vapour and anthropogenic gases: The roles of water vapour, rainfall and solar radiation in determining air temperature change measured at Bet Dagan, Israel between 1964 and 2010 – Stanhill et al. (2012)

Changes in diurnal temperature range in Bangladesh: Changes in diurnal temperature range in Bangladesh during the time period 1961–2008 – Shahid et al. (2012)

In Spain total cloud cover increased until 1960s when it started to decrease: Increasing cloud cover in the 20th century: review and new findings in Spain – Sanchez-Lorenzo et al. (2012)

Large methane emission upon spring thaw from natural wetlands in the northern permafrost region: Large methane emission upon spring thaw from natural wetlands in the northern permafrost region – Song et al. (2012)

Over past 50 years, tree growth decline has prevailed despite increasing atmospheric carbon dioxide: Probing for the influence of atmospheric CO2 and climate change on forest ecosystems across biomes – Silva & Madhur (2012)

Particular combinations of temperature and moisture can interact directly or indirectly to limit species ranges even when these factors alone do not exceed species tolerances: The relative influence of temperature, moisture and their interaction on range limits of mammals over the past century – Smith (2012)

Urban traffic restrictions could help attain global CO2 reduction targets: Satellite-based estimates of reduced CO and CO2 emissions due to traffic restrictions during the 2008 Beijing Olympics – Worden et al. (2012)

Atmospheric methane increase during the abrupt warming of Younger Dryas termination might have been mostly from biomass burning: Enrichment in 13C of atmospheric CH4 during the Younger Dryas termination – Melton et al. (2012)

Damage potential of a potato pest species might increase in future: Predicting climate-change-caused changes in global temperature on potato tuber moth Phthorimaea operculella (Zeller) distribution and abundance using phenology modeling and GIS mapping – Kroschel et al. (2012)

Carbon emissions of Chinese cities: The carbon emissions of Chinese cities – Wang et al. (2012)

Satellite retrieval of the liquid water fraction in tropical clouds: Satellite retrieval of the liquid water fraction in tropical clouds between −20 and −38 °C – Mitchell & d’Entremont (2012)

Near real time satellite estimates of global biomass burning emissions: Near real time global biomass burning emissions product from geostationary satellite constellation – Zhang et al. (2012)

North Atlantic Oscillation affects North Atlantic Ocean carbon dioxide uptake: Multi-decadal uptake of carbon dioxide into subtropical mode water of the North Atlantic Ocean – Bates (2012)

How snow-albedo feedback affects Swiss spring temperatures: Snow-albedo feedback and Swiss spring temperature trends – Scherrer et al. (2012)

Subduction of Mode Water has intensified in the South Pacific during 20th century: An Intensification Trend of South Pacific Mode Water Subduction Rates over the 20th Century – Liu & Wu (2012)

Aerial photos show increase in erect shrubs in extensively warmed Low Arctic region: Recent expansion of erect shrubs in the Low Arctic: evidence from Eastern Nunavik – Tremblay et al. (2012)

The potential of enhanced weathering in the UK: The potential of enhanced weathering in the UK – Renforth (2012)

Medieval winters were cooler and summers were warmer than late 20th century in Scotland: Marine climatic seasonality during early medieval times (10th to 12th centuries) based on isotopic records in Viking Age shells from Orkney, Scotland – Surge & Barrett (2012)

Satellite Oceanography and Climate Change: Satellite Oceanography and Climate Change – Garcia-Soto et al. (2012)

New analysis on Toba super-eruption: Did the 73 ka Toba super-eruption have an enduring effect? Insights from genetics, prehistoric archaeology, pollen analysis, stable isotope geochemistry, geomorphology, ice cores, and climate models – Williams (2012)

Consistent estimates from satellites and models for the first aerosol indirect forcing: Consistent estimates from satellites and models for the first aerosol indirect forcing – Penner et al. (2012)

Interdecadal variability/long-term changes in global precipitation patterns: Interdecadal variability/long-term changes in global precipitation patterns during the past three decades: global warming and/or pacific decadal variability? – Gu & Adler (2012)

Southeastern United States was one of the rare places that cooled during 20th century: The 20th century cooling trend over the southeastern United States – Rogers (2012)

Predicted warming is unlikely to have major effects on squid but acidification may have greater impact: Role of squid in the Southern Ocean pelagic ecosystem and the possible consequences of climate change – Rodhouse (2012)

Shifting Avian elevational ranges with changing climate: The push and pull of climate change causes heterogeneous shifts in avian elevational ranges – Tingley et al. (2012)

Deer browsing affects temperature response of tree species: Sapling growth responses to warmer temperatures ‘cooled’ by browse pressure – Fisichelli et al. (2012)

Livestock greenhouse gas emissions and mitigation potential in Europe: Livestock greenhouse gas emissions and mitigation potential in Europe – Bellarby et al. (2012)

When calculating ice mass, remember to include small glaciers: Significant contribution to total mass from very small glaciers – Bahr & Radić (2012)

Capacity of North Atlantic surface waters to absorb carbon dioxide has diminished: Detecting anthropogenic carbon dioxide uptake and ocean acidification in the North Atlantic Ocean – Bates et al. (2012)

Measuring GHG’s from solar radiation: Remote sensing of CO2 and CH4 using solar absorption spectrometry with a low resolution spectrometer – Petri et al. (2012)

Identification of climatic state with limited proxy data: Identification of climatic state with limited proxy data – Annan & Hargreaves (2012)

Global and regional multi-annual (1996–2003) analysis of cloud properties: Seven years of global retrieval of cloud properties using space-borne data of GOME – Lelli et al. (2012)

Latitudinally asymmetric response of global surface temperature: Latitudinally asymmetric response of global surface temperature: Implications for regional climate change – Xu & Ramanathan (2012)

Future Baltic Sea ecosystem may unprecedentedly change compared to the past 150 yr: Comparing reconstructed past variations and future projections of the Baltic Sea ecosystem—first results from multi-model ensemble simulations – Meier et al. (2012)

Measurements show Earth’s greenhouse effect: Solar and thermal radiation profiles and radiative forcing measured through the atmosphere – Philipona et al. (2012)

Ice mass loss continues at high rate in Larsen B Ice Shelf: Mass loss of Larsen B tributary glaciers (Antarctic Peninsula) unabated since 2002 – Berthier et al. (2012)

Colombia bird species are projected to lose on average between 33 and 43 % of their total range under future climate: Effects of climate change on species distribution, community structure, and conservation of birds in protected areas in Colombia – Velásquez-Tibatá et al. (2012)

Honey, we shrunk the Alps’ snow cover: The snowline climate of the Alps 1961–2010 – Hantel et al. (2012)

Icebergs have an effect on ocean circulation: Simulating Heinrich event 1 with interactive icebergs – Jongma et al. (2012)

Historical and future changes in temperature extremes over Europe: Historical and future changes in maximum and minimum temperature records over Europe – Elguindi et al. (2012)

Parisian heat island is projected to decrease with global warming: Evolution of the Parisian urban climate under a global changing climate – Lemonsu et al. (2012)

European Alps glacier mass balance: Extrapolating glacier mass balance to the mountain-range scale: the European Alps 1900–2100 – Huss (2012)

More on climate regime shifts: Directional influences on global temperature prediction – Wang et al. (2012)

How to define Anthropocene?: The stratigraphic status of the Anthropocene – Gale & Hoare (2012)

The atmospheric lifetime of black carbon: The atmospheric lifetime of black carbon – Cape et al. (2012)

AMOC variability and climatic influence: Multicentennial variability of the Atlantic meridional overturning circulation and its climatic influence in a 4000 year simulation of the GFDL CM2.1 climate model – Delworth & Zeng (2012)

Study found that projected warming shortened mosquito lifespan, which in turn decreased the potential dengue season in 3 U.S. cities: Potential impacts of climate change on the ecology of dengue and its mosquito vector the Asian tiger mosquito (Aedes albopictus) – Erickson et al. (2012)

The relationship of Indian summer monsoon and sunspot cycle: The Indian summer monsoon during peaks in the 11 year sunspot cycle – van Loon & Meehl (2012)

Western tropical Pacific sea level changes are well explained by global sea-level rise and trade wind fluctuations: Multidecadal sea level anomalies and trends in the western tropical Pacific – Merrifield et al. (2012)

Stepwise changes in stratospheric water vapor: Stepwise changes in stratospheric water vapor? – Fueglistaler (2012)

Stratospheric water vapor and climate: Stratospheric water vapor and climate: Sensitivity to the representation in radiation codes – Maycock & Shine (2012)

Study demonstrates the importance of including preindustrial emissions for the most scientifically defensible attribution: Attribution of atmospheric CO2 and temperature increases to regions: importance of preindustrial land use change – Pongratz & Caldeira (2012)

Increasingly high temperatures might have negative implications for the fitness of arid-zone birds: The costs of keeping cool in a warming world: implications of high temperatures for foraging, thermoregulation and body condition of an arid-zone bird – du Plessis et al. (2012)

Correlation of Caribbean precipitation and AMO during past 1300 years: Cuban stalagmite suggests relationship between Caribbean precipitation and the Atlantic Multidecadal Oscillation during the past 1.3 ka – Fensterer et al. (2012)

One more paper reporting evidence of ozone recovery: Development of a climate record of tropospheric and stratospheric column ozone from satellite remote sensing: evidence of an early recovery of global stratospheric ozone – Ziemke & Chandra (2012)

Problems in identifying weekly cycles in meteorological variables: Identifying weekly cycles in meteorological variables: The importance of an appropriate statistical analysis – Daniel et al. (2012)

Problems in identifying weekly cycles in meteorological variables 2: Assessing large-scale weekly cycles in meteorological variables: a review – Sanchez-Lorenzo et al. (2012)

Are Swiss temperature series taking a break?: Break detection of annual Swiss temperature series – Kuglitsch et al. (2012)

There they go blaming SAM for sudden cloud cover changes: Understanding sudden changes in cloud amount: The Southern Annular Mode and South American weather fluctuations – Laken & Pallé (2012)


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New research from last week 26/2012

Posted by Ari Jokimäki on July 2, 2012

After this post, there will be four week (boreal) summer break in the new research from last week series. For new research during this break, although I’m not making any promises, it is possible that there are some updates in AGW Observer’s Twitter and/or Facebook pages.

Last week brought you studies on fire regimes, windstorms, fog, costs, sea level, glacier, black carbon, ocean acidification, Holocen thermal maximum, rain forest, among dozens of others.

With climate change more Bornean rain forest trees get killed by droughts

Drought-induced mortality of a Bornean tropical rain forest amplified by climate change – Kumagai & Porporato (2012)

Abstract: “Drought-related tree mortality at a regional scale causes drastic shifts in carbon and water cycling in Southeast Asian tropical rain forests, where severe droughts are projected to occur more frequently, especially under El Niño conditions. We examine how the mortality of a Bornean tropical rain forest is altered by projected shifts in rainfall, using field measurements, global climate model (GCM) simulation outputs, and an index developed for drought-induced tree mortality (Tree Death Index η) associated with a stochastic ecohydrological model. All model parameters have clear physical meanings and were obtained by field observations. Rainfall statistics as primary model forcing terms are constructed from long-term rainfall records for the late 20th century, and 14 GCM rainfall projections for the late 21st century. These statistics indicate that there were sporadic severe droughts corresponding with El Niño events, generally occurring in January–March, and that seasonality in rainfall will become more pronounced, e.g., dry (January–March) seasons becoming drier and wet (October–December) seasons becoming wetter. The computed η well reflects high tree mortality under severe drought during the 1997–1998 El Niño event. For the present, model results demonstrate high and low probabilities of mortality in January–March and October–December, respectively, and they predict that the difference in such probabilities will increase in the future. Such high probability of mortality in the dry season is still significantly high, even considering the beneficial effect of increased soil water storage in the wet season (which is projected to increase in the late 21st century).”

Citation: Kumagai, T., and A. Porporato (2012), Drought-induced mortality of a Bornean tropical rain forest amplified by climate change, J. Geophys. Res., 117, G02032, doi:10.1029/2011JG001835.

When was Holocene Thermal Maximum in different regions?

Global characterization of the Holocene Thermal Maximum – Renssen et al. (2012)

Abstract: “We analyze the global variations in the timing and magnitude of the Holocene Thermal Maximum (HTM) and their dependence on various forcings in transient simulations covering the last 9000 years (9 ka), performed with a global atmosphere-ocean-vegetation model. In these experiments, we consider the influence of variations in orbital parameters and atmospheric greenhouse gases and the early-Holocene deglaciation of the Laurentide Ice sheet (LIS). Considering the LIS deglaciation, we quantify separately the impacts of the background melt-water fluxes and the changes in topography and surface albedo. In the analysis we focus on the intensity of the maximum temperature deviation relative to the preindustrial level, its timing in the Holocene, and the seasonal expression. In the model, the warmest HTM conditions are found at high latitudes in both hemispheres, reaching 5 °C above the preindustrial level, while the smallest HTM signal is seen over tropical oceans (less than 0.5 °C). This latitudinal contrast is mostly related to the nature of the orbitally-forced insolation forcing, which is also largest at high latitudes, and further enhanced by the polar amplification. The Holocene timing of the HTM is earliest (before 8 ka BP) in regions not affected by the remnant LIS, particularly NW North America, E Asia, N Africa, N South America, the Middle East, NE Siberia and Australia. Compared to the early Holocene insolation maximum, the HTM was delayed by 2–3 ka over NE North America, and regions directly downwind from the LIS. A similar delay is simulated over the Southern Ocean, while an intermediate lag of about 1 ka is found over most other continents and oceans. The seasonal timing of the HTM over continents generally occurs in the same month as the maximum insolation anomaly, whereas over oceans the HTM is delayed by 2–3 months. Exceptions are the oceans covered by sea ice and North Africa, were additional feedbacks results in a different seasonal timing. The simulated timing and magnitude of the HTM are generally consistent with global proxy evidence, with some notable exceptions in the Mediterranean region, SW North America and eastern Eurasia.”

Citation: H. Renssen, H. Seppä, X. Crosta, H. Goosse, D.M. Roche, Quaternary Science Reviews, Volume 48, 10 August 2012, Pages 7–19,

Arctic sea ice disappears faster than projected -> ocean acidifies faster

Impact of rapid sea-ice reduction in the Arctic Ocean on the rate of ocean acidification – Yamamoto et al. (2012) [FULL TEXT]

Abstract: “The largest pH decline and widespread undersaturation with respect to aragonite in this century due to uptake of anthropogenic carbon dioxide in the Arctic Ocean have been projected. The reductions in pH and aragonite saturation state in the Arctic Ocean have been caused by the melting of sea ice as well as by an increase in the concentration of atmospheric carbon dioxide. Therefore, future projections of pH and aragonite saturation in the Arctic Ocean will be affected by how rapidly the reduction in sea ice occurs. The observed recent Arctic sea-ice loss has been more rapid than projected by many of the climate models that contributed to the Intergovernmental Panel on Climate Change Fourth Assessment Report. In this study, the impact of sea-ice reduction rate on projected pH and aragonite saturation state in the Arctic surface waters was investigated. Reductions in pH and aragonite saturation were calculated from the outputs of two versions of an Earth system model with different sea-ice reduction rates under similar CO2 emission scenarios. The newer model version projects that Arctic summer ice-free condition will be achieved by the year 2040, and the older version predicts ice-free condition by 2090. The Arctic surface water was projected to be undersaturated with respect to aragonite in the annual mean when atmospheric CO2 concentration reaches 513 (606) ppm in year 2046 (2056) in new (old) version. At an atmospheric CO2 concentration of 520 ppm, the maximum differences in pH and aragonite saturation state between the two versions were 0.1 and 0.21 respectively. The analysis showed that the decreases in pH and aragonite saturation state due to rapid sea-ice reduction were caused by increases in both CO2 uptake and freshwater input. Thus, the reductions in pH and aragonite saturation state in the Arctic surface waters are significantly affected by the difference in future projections for sea-ice reduction rate. Our results suggest that the future reductions in pH and aragonite saturation state could be significantly faster than previously projected if the sea-ice reduction in the Arctic Ocean keeps its present pace.”

Citation: Yamamoto, A., Kawamiya, M., Ishida, A., Yamanaka, Y., and Watanabe, S.: Impact of rapid sea-ice reduction in the Arctic Ocean on the rate of ocean acidification, Biogeosciences, 9, 2365-2375, doi:10.5194/bg-9-2365-2012, 2012.

Review of current model estimates of black carbon radiative effects

Assessment of black carbon radiative effects in climate models – Feichter & Stier (2012)

Abstract: “Black carbon (BC) from the burning of fossil fuel and biomass absorbs solar radiation and might intensify the greenhouse gas warming. Therefore, ideas to combat climate warming by reducing black carbon emissions emerged. However, black carbon emissions are generally accompanied by co-emission of other aerosols that predominantly scatter and have a cooling effect, so that the net forcing is substantially smaller, reducing mitigation potentials. Moreover, indirect effects on clouds are likely to exert additional cooling. As in situ measurements do not sufficiently sample the global atmosphere and satellite data does not provide the necessary detail on aerosol absorption, our only tools to estimate the effect of mitigation are numerical climate models. A review of current model estimates of black carbon radiative effects gives an average estimate of the direct radiative forcing as +0.33 W/m2, indirect effects of −0.11 W/m2 and through BC deposition on snow/ice surfaces of about +0.05 W/m2. A key limitation of these estimates is that the numerical models required for their global quantification are insufficiently constrained by observations. In addition, the comparison of instantaneous forcings generally overestimates the relative importance of black carbon and policy makers should consider alternative metrics, incorporating time-horizons.”

Citation: Johann Feichter, Philip Stier, Wiley Interdisciplinary Reviews: Climate Change, DOI: 10.1002/wcc.180.

Langfjordjøkelen glacier in Norway is shrinking rapidly

Langfjordjøkelen, a rapidly shrinking glacier in northern Norway – Andreassen et al. (2012)

Abstract: “In this paper we document changes of Langfjordjøkelen, a small ice cap in northern Norway. Surface mass-balance measurements have been carried out on an east-facing part (3.2 km2) of the ice cap since 1989. Measurements reveal a strong thinning; the balance year 2008/09 was the 13th successive year with significant negative annual balance (≤-0.30 m w.e.). The average annual deficit was 0.9 m w.e. over 1989-2009. The recent thinning of Langfjordjøkelen is stronger than observed for any other glacier in mainland Norway. Maps from 1966, 1994 and 2008 show that the whole ice cap is shrinking. The total volume loss over 1966-2008 was 0.264 km3. The east-facing part has been greatly reduced in volume (46%), area (38%) and length (20%). For this part over 1994-2008, the cumulative direct mass balance (-14.5 m w.e.) is less negative than the geodetic mass balance (-17.7 m w.e.). A surface mass-balance model using upper-air meteorological data was used to reconstruct annual balances back to 1948 and to reconstruct unmeasured years 1994 and 1995. Sensitivity of annual balance to 1°C warming is -0.76 m w.e. and to 10% increase in precipitation is +0.20 m w.e.”

Citation: Andreassen, Liss M.; Kjøllmoen, Bjarne; Rasmussen, Al; Melvold, Kjetil; Nordli, Øyvind, Journal of Glaciology, Volume 58, Number 209, June 2012 , pp. 581-593(13), DOI:

Arctic Ocean sea level at European coast used to follow Arctic Oscillation but doesn’t anymore

Tide gauge-based sea level variations since 1950 along the Norwegian and Russian coasts of the Arctic Ocean; Contribution of the steric components – Henry et al. (2012)

Abstract: “We investigate sea level change and variability in part of the Arctic region over the 1950-2009 period. Analysis of 62 long tide gauge records along the Norwegian and Russian coastlines shows that coastal mean sea level in these two areas was almost stable until about 1980 but since then displayed a clear increasing trend, following fluctuations of Arctic Oscillation. After the mid-to-late 1990s the co-fluctuation with the AO disappears, to achieve an increasing trend of ~4 mm/yr since 1995. Using in situ ocean temperature and salinity data from three different databases, we estimated the thermosteric, halosteric and steric sea level since 1970 in the North Atlantic and Nordic Seas region (incomplete data coverage prevented us to analyze steric data along the Russian coast). We note a strong anti-correlation between the thermosteric and halosteric components both in terms of spatial trends and regionally averaged time series. The latter show a strong change as of ~1995 that indicates increase in temperature and salinity, confirmed by the Empirical Orthogonal Function decomposition. Regionally steric data are compared to altimetry-based sea level over 1993-2009. Spatial trend patterns of altimetry-based sea level are largely explained by steric patterns, but residual spatial trends suggest that other factors contribute. Focusing on Norwegian tide gauges, we compare observed coastal mean sea level with the steric sea level and the ocean mass component estimated with GRACE gravimetry data (since 2003) and conclude that the mass component partly explains the sustained sea level rise (of ~4 mm/yr) over the altimetry era.”

Citation: Henry, O., pierre prandi, W. Llovel, A. Cazenave, S. Jevrejeva, D. Stammer, B. Meyssignac, and N. V. Koldunov (2012), Tide gauge-based sea level variations since 1950 along the Norwegian and Russian coasts of the Arctic Ocean; Contribution of the steric components, J. Geophys. Res., doi:10.1029/2011JC007706, in press.

Climate change costs United States 1 trillion $ and 7 million full-time jobs in next 40 years

The near-term risk of climate uncertainty among the U.S. states – Backus et al. (2012)

Abstract: “This article describes a study employing a risk-assessment methodology for evaluating uncertain future climatic conditions. To understand the implications of uncertainty on risk and to provide a near-term rationale for policy interventions, the study estimated the impacts from responses to climate change on U.S. state- and national-level economic activity. The study used results of the climate-model CMIP3 dataset developed for the Intergovernmental Panel on Climate Change’s (IPCC) Fourth Assessment Report to 1) estimate a proxy for representing climate uncertainty over the next 40 years, 2) map the simulated weather from the climate models hydrologically to the county level to determine the physical consequences on economic activity at the state level, and 3) perform a detailed, economy-wide, 70-industry analysis of economic impacts among the interdependent lower-48 states for the years 2010 through 2050. The analysis determined the interacting industry-level effects, employment impacts at the state level, interstate population migration, consequences to personal income, and ramifications for the U.S. trade balance. When compared to a baseline economic forecast, the calculations produced an average risk of damage of $1 trillion to the U.S. economy from climate change over the next 40 years, with losses in employment equivalent to nearly 7 million full-time jobs. Added uncertainty would increase the estimated risk.”

Citation: George A. Backus, Thomas S. Lowry and Drake E. Warren, Climatic Change, 2012, DOI: 10.1007/s10584-012-0511-8.

South Asia has gotten more foggy

On the fog variability over south Asia – Syed et al. (2012) [FULL TEXT]

Abstract: “An increasing trend in fog frequencies over south Asia during winter in the last few decades has resulted in large economical losses and has caused substantial difficulties in the daily lives of people. In order to better understand the fog phenomenon, we investigated the climatology, inter-annual variability and trends in the fog occurrence from 1976 to 2010 using observational data from 82 stations, well distributed over India and Pakistan. Fog blankets large area from Pakistan to Bangladesh across north India from west to east running almost parallel to south of the Himalayas. An EOF analysis revealed that the fog variability over the whole region is coupled and therefore must be governed by some large scale phenomenon on the inter-annual time scale. Significant positive trends were found in the fog frequency but this increase is not gradual, as with the humidity, but comprises of two distinct regimes shifts, in 1990 and 1998, with respect to both mean and variance. The fog is also detected in ERA-Interim 3 hourly, surface and model level forecast data when using the concept of “cross-over temperature” combined with boundary layer stability. This fog index is able to reproduce the regime shift around 1998 and shows that the method can be applied to analyze fog over south Asia. The inter-annual variability seems to be associated with the wave train originating from the North Atlantic in the upper troposphere that when causing higher pressure over the region results in an increased boundary layer stability and surface-near relative humidity. The trend and shifts in the fog occurrence seems to be associated with the gradual increasing trend in relative humidity from 1990 onwards.”

Citation: F. S. Syed, H. Körnich and M. Tjernström, Climate Dynamics, 2012, DOI: 10.1007/s00382-012-1414-0.

Netherlands is currently experiencing a minimum in windstorms

A 101 year record of windstorms in the Netherlands – Cusack (2012)

Abstract: “A 101 year time-series of storm losses in the Netherlands is developed from the near-surface wind speed records at five Dutch stations. Station metadata combined with results from statistical tests were used to homogenise the data and retain the temporal variability driven solely by changes in climate processes. The wind speed data were transformed into storm damage using a model measuring loss impacts upon society. The resulting windstorm loss time-series for the Netherlands contains some interesting features. Annual losses are stable over the whole period and have a dominant cycle with a period of about 50 years. The Netherlands is currently experiencing the minimum aggregate storm damage of the past 100 years, though only slightly lower than a quiet period of 50 years ago. Both of these minima are driven primarily by lowered rates of occurrence of damaging storms. However, further analysis reveals the present-day minimum has different characteristics from the previous lull: currently, the frequency of stronger storms is slightly above the previous minimum whereas the frequency of weaker storms is uniquely low. A seasonal analysis provides more information: there is a dearth of damaging storms in the earlier half of the storm season in the present day; since this period contains generally weaker storms, this seasonality is also manifested as a lack of weaker storms. These results suggest a different mix of climate forcing mechanisms in modern times compared to 50 years ago, in the earlier half of the storm season.”

Citation: Stephen Cusack, Climatic Change, 2012, DOI: 10.1007/s10584-012-0527-0.

Climate change driven shift in fire regimes may occur by the 2020s in British Columbia

Potential effect of climate change on observed fire regimes in the Cordilleran forests of South-Central Interior, British Columbia – Nitschke & Innes (2012)

Abstract: “Climate change is predicted to result in a warmer and drier climate in many parts of the world, including south-central British Columbia. With a shift in climate, a change in fire regimes is likely to occur. In this study, a statistically significant increase in mean fire size was predicted to occur along with an increase maximum fire size and decrease in the mean fire interval. A change in these fire regime characteristics suggests a climate-change driven shift in fire regimes may occur by the 2020s. The shift in fire regime suggests the proportion of the landscape burning every 50 years or less will increase from 34 % to 93 % by the 2080s. Change in fire regimes will have direct implications for ecosystem management as the combination of large, flammable fuel types and fire-prone climatic conditions will increase the risk of larger more frequent fires and increase the costs and dangers involved in managing fire-prone forests in the Cordilleran region of south-central British Columbia. The climate change-driven shift in fire regime questions the use of historic fire regime characteristics for determining landscape-level conservation targets within the study area.”

Citation: Craig R. Nitschke and John L. Innes, Climatic Change, 2012, DOI: 10.1007/s10584-012-0522-5.

CLASSIC OF THE WEEK: Damon et al. (1978)

Temporal Fluctuations of Atmospheric 14C: Causal Factors and Implications – Damon et al. (2012) [FULL TEXT]

Abstract: No abstract. Quote from the beginning of the article: “In this review we consider the time variations of the atmospheric concentration of 14C, a radioisotope induced by cosmic rays and also known as radiocarbon.”

Citation: Damon, Paul E., Lerman, Juan Carlos, Long, Austin, Annual Review of Earth and Planetary Sciences, Vol. 6, p.457, DOI: 10.1146/annurev.ea.06.050178.002325.

When each paper is published, it is notified in AGW Observer Facebook page and Twitter page. Here’s the archive for the research papers of previous weeks. If this sort of thing interests you, be sure to check out A Few Things Illconsidered. They also have a weekly posting containing lots of links to new research and other climate related news.

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