48 results on '"Skeie, R. B."'
Search Results
2. An AeroCom Assessment of Black Carbon in Arctic Snow and Sea Ice
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Jiao, C, Flanner, M. G, Balkanski, Y, Bauer, S. E, Bellouin, N, Bernsten, T. K, Bian, H, Carslaw, K. S, Chin, M, DeLuca, N, Diehl, T, Ghan, S. J, Iversen, T, Kirkevag, A, Koch, D, Liu, X, Mann, G. W, Penner, J. E, Pitari, G, Schulz, M, Seland, O, Skeie, R. B, Steenrod, S. D, Stier, P, and Tkemura, T
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Meteorology And Climatology - Abstract
Though many global aerosols models prognose surface deposition, only a few models have been used to directly simulate the radiative effect from black carbon (BC) deposition to snow and sea ice. Here, we apply aerosol deposition fields from 25 models contributing to two phases of the Aerosol Comparisons between Observations and Models (AeroCom) project to simulate and evaluate within-snow BC concentrations and radiative effect in the Arctic. We accomplish this by driving the offline land and sea ice components of the Community Earth System Model with different deposition fields and meteorological conditions from 2004 to 2009, during which an extensive field campaign of BC measurements in Arctic snow occurred. We find that models generally underestimate BC concentrations in snow in northern Russia and Norway, while overestimating BC amounts elsewhere in the Arctic. Although simulated BC distributions in snow are poorly correlated with measurements, mean values are reasonable. The multi-model mean (range) bias in BC concentrations, sampled over the same grid cells, snow depths, and months of measurements, are −4.4 (−13.2 to +10.7) ng/g for an earlier phase of AeroCom models (phase I), and +4.1 (−13.0 to +21.4) ng/g for a more recent phase of AeroCom models (phase II), compared to the observational mean of 19.2 ng/g. Factors determining model BC concentrations in Arctic snow include Arctic BC emissions, transport of extra-Arctic aerosols, precipitation, deposition efficiency of aerosols within the Arctic, and meltwater removal of particles in snow. Sensitivity studies show that the model-measurement evaluation is only weakly affected by meltwater scavenging efficiency because most measurements were conducted in non-melting snow. The Arctic (60-90degN) atmospheric residence time for BC in phase II models ranges from 3.7 to 23.2 days, implying large inter-model variation in local BC deposition efficiency. Combined with the fact that most Arctic BC deposition originates from extra-Arctic emissions, these results suggest that aerosol removal processes are a leading source of variation in model performance. The multi-model mean (full range) of Arctic radiative effect from BC in snow is 0.15 (0.07-0.25) W/sq m and 0.18 (0.06-0.28) W/sq m in phase I and phase II models, respectively. After correcting for model biases relative to observed BC concentrations in different regions of the Arctic, we obtain a multi-model mean Arctic radiative effect of 0.17 W/sq m for the combined AeroCom ensembles. Finally, there is a high correlation between modeled BC concentrations sampled over the observational sites and the Arctic as a whole, indicating that the field campaign provided a reasonable sample of the Arctic.
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- 2014
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3. Multi-Model Mean Nitrogen and Sulfur Deposition from the Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP): Evaluation of Historical and Projected Future Changes
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Lamarque, J.-F, Dentener, F, McConnell, J, Ro, C.-U, Shaw, M, Vet, R, Bergmann, D, Cameron-Smith, P, Dalsoren, S, Doherty, R, Faluvegi, G, Ghan, S. J, Josse, B, Lee, Y. H, MacKenzie, I. A, Plummer, D, Shindell, D. T, Skeie, R. B, Stevenson, D. S, Strode, S, Zeng, G, Curran, M, Dahl-Jensen, D, Das, S, Fritzsche, D, and Nolan, M
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Earth Resources And Remote Sensing ,Meteorology And Climatology - Abstract
We present multi-model global datasets of nitrogen and sulfate deposition covering time periods from 1850 to 2100, calculated within the Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP). The computed deposition fluxes are compared to surface wet deposition and ice core measurements.We use a new dataset of wet deposition for 2000-2002 based on critical assessment of the quality of existing regional network data. We show that for present day (year 2000 ACCMIP time slice), the ACCMIP results perform similarly to previously published multi-model assessments. For this time slice, we find a multimodel mean deposition of approximately 50 Tg(N) yr−1 from nitrogen oxide emissions, 60 Tg(N) yr−1 from ammonia emissions, and 83 Tg(S) yr−1 from sulfur emissions. The analysis of changes between 1980 and 2000 indicates significant differences between model and measurements over the United States but less so over Europe. This difference points towards a potential misrepresentation of 1980 NH3 emissions over North America. Based on ice core records, the 1850 deposition fluxes agree well with Greenland ice cores, but the change between 1850 and 2000 seems to be overestimated in the Northern Hemisphere for both nitrogen and sulfur species. Using the Representative Concentration Pathways (RCPs) to define the projected climate and atmospheric chemistry related emissions and concentrations, we find large regional nitrogen deposition increases in 2100 in Latin America, Africa and parts of Asia under some of the scenarios considered. Increases in South Asia are especially large, and are seen in all scenarios, with 2100 values more than double their 2000 counterpart in some scenarios and reaching >1300 mg(N)m−2 yr−1 averaged over regional to continental-scale regions in RCP 2.6 and 8.5, 30-50% larger than the values in any region currently (circa 2000). However, sulfur deposition rates in 2100 are in all regions lower than in 2000 in all the RCPs. The new ACCMIP multimodel deposition dataset provides state-of-the-science, consistent and evaluated time slice (spanning 1850-2100) global gridded deposition fields for use in a wide range of climate and ecological studies.
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- 2013
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4. Tropospheric Ozone Changes, Radiative Forcing and Attribution to Emissions in the Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP)
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Stevenson, D.S, Young, P.J, Naik, V, Lamarque, J.-F, Shindell, D. T, Voulgarakis, A, Skeie, R. B, Dalsoren, S. B, Myhre, G, Berntsen, T. K, Folberth, G. A, Rumbold, S. T, Collins, W. J, MacKenzie, I. A, Doherty, R. M, Zeng, G, vanNoije, T. P. C, Strunk, A, Bergmann, D, Cameron-Smith, P, Plummer, D. A, Strode, S. A, Horowitz, L, Lee, Y. H, Szopa, S, Sudo, K, Nagashima, T, Josse, B, Cionni, I, Righi, M, Eyring, V, Conley, A, Bowman, K. W, Wild, O, and Archibald, A
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Meteorology And Climatology - Abstract
Ozone (O3) from 17 atmospheric chemistry models taking part in the Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP) has been used to calculate tropospheric ozone radiative forcings (RFs). All models applied a common set of anthropogenic emissions, which are better constrained for the present-day than the past. Future anthropogenic emissions follow the four Representative Concentration Pathway (RCP) scenarios, which define a relatively narrow range of possible air pollution emissions. We calculate a value for the pre-industrial (1750) to present-day (2010) tropospheric ozone RF of 410 mW m−2. The model range of pre-industrial to present-day changes in O3 produces a spread (+/-1 standard deviation) in RFs of +/-17%. Three different radiation schemes were used - we find differences in RFs between schemes (for the same ozone fields) of +/-10 percent. Applying two different tropopause definitions gives differences in RFs of +/-3 percent. Given additional (unquantified) uncertainties associated with emissions, climate-chemistry interactions and land-use change, we estimate an overall uncertainty of +/-30 percent for the tropospheric ozone RF. Experiments carried out by a subset of six models attribute tropospheric ozone RF to increased emissions of methane (44+/-12 percent), nitrogen oxides (31 +/- 9 percent), carbon monoxide (15 +/- 3 percent) and non-methane volatile organic compounds (9 +/- 2 percent); earlier studies attributed more of the tropospheric ozone RF to methane and less to nitrogen oxides. Normalising RFs to changes in tropospheric column ozone, we find a global mean normalised RF of 42 mW m(−2) DU(−1), a value similar to previous work. Using normalised RFs and future tropospheric column ozone projections we calculate future tropospheric ozone RFs (mW m(−2); relative to 1750) for the four future scenarios (RCP2.6, RCP4.5, RCP6.0 and RCP8.5) of 350, 420, 370 and 460 (in 2030), and 200, 300, 280 and 600 (in 2100). Models show some coherent responses of ozone to climate change: decreases in the tropical lower troposphere, associated with increases in water vapour; and increases in the sub-tropical to mid-latitude upper troposphere, associated with increases in lightning and stratosphere-to-troposphere transport. Climate change has relatively small impacts on global mean tropospheric ozone RF.
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- 2013
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5. Evaluation of preindustrial to present-day black carbon and its albedo forcing from Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP)
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Lee, Y. H, Lamarque, J.-F, Flanner, M. G, Jiao, C, Shindell, D. T, Bernsten, T, Bisiaux, M. M, Cao, J, Collins, W. J, Curran, M, Edwards, R, Faluvegi, G, Ghan, S, Horowitz, L. W, McConnell, J. R, Ming, J, Myhre, G, Nagashima, T, Naik, V, Rumbold, S. T, Skeie, R. B, Sudo, K, Takemura, T, Thevenon, F, Xu, B, and Yoon, J.-H
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Meteorology And Climatology - Abstract
As part of the Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP), we evaluate the historical black carbon (BC) aerosols simulated by 8 ACCMIP models against observations including 12 ice core records, long-term surface mass concentrations, and recent Arctic BC snowpack measurements. We also estimate BC albedo forcing by performing additional simulations using offline models with prescribed meteorology from 1996-2000. We evaluate the vertical profile of BC snow concentrations from these offline simulations using the recent BC snowpack measurements. Despite using the same BC emissions, the global BC burden differs by approximately a factor of 3 among models due to differences in aerosol removal parameterizations and simulated meteorology: 34 Gg to 103 Gg in 1850 and 82 Gg to 315 Gg in 2000. However, the global BC burden from preindustrial to present-day increases by 2.5-3 times with little variation among models, roughly matching the 2.5-fold increase in total BC emissions during the same period.We find a large divergence among models at both Northern Hemisphere (NH) and Southern Hemisphere (SH) high latitude regions for BC burden and at SH high latitude regions for deposition fluxes. The ACCMIP simulations match the observed BC surface mass concentrations well in Europe and North America except at Ispra. However, the models fail to predict the Arctic BC seasonality due to severe underestimations during winter and spring. The simulated vertically resolved BC snow concentrations are, on average, within a factor of 2-3 of the BC snowpack measurements except for Greenland and the Arctic Ocean. For the ice core evaluation, models tend to adequately capture both the observed temporal trends and the magnitudes at Greenland sites. However, models fail to predict the decreasing trend of BC depositions/ice core concentrations from the 1950s to the 1970s in most Tibetan Plateau ice cores. The distinct temporal trend at the Tibetan Plateau ice cores indicates a strong influence from Western Europe, but the modeled BC increases in that period are consistent with the emission changes in Eastern Europe, the Middle East, South and East Asia. At the Alps site, the simulated BC suggests a strong influence from Europe, which agrees with the Alps ice core observations. At Zuoqiupu on the Tibetan Plateau, models successfully simulate the higher BC concentrations observed during the non-monsoon season compared to the monsoon season but overpredict BC in both seasons. Despite a large divergence in BC deposition at two Antarctic ice core sites, some models with a BC lifetime of less than 7 days are able to capture the observed concentrations. In 2000 relative to 1850, globally and annually averaged BC surface albedo forcing from the offline simulations ranges from 0.014 to 0.019Wm−2 among the ACCMIP models. Comparing offline and online BC albedo forcings computed by some of the same models, we find that the global annual mean can vary by up to a factor of two because of different aerosol models or different BC-snow parameterizations and snow cover. The spatial distributions of the offline BC albedo forcing in 2000 show especially high BC forcing (i.e., over 0.1W/sq. m) over Manchuria, Karakoram, and most of the Former USSR. Models predict the highest global annual mean BC forcing in 1980 rather than 2000, mostly driven by the high fossil fuel and biofuel emissions in the Former USSR in 1980.
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- 2013
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6. Black Carbon Vertical Profiles Strongly Affect Its Radiative Forcing Uncertainty
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Samset, B. H, Myhre, G, Schulz, M, Balkanski, Y, Bauer, S, Berntsen, T. K, Bian, H, Bellouin, N, Diehl, T, Easter, R. C, Ghan, S. J, Iversen, T, Kinne, S, Kirkevag, A, Lamarque, J.-F, Lin, G, Liu, X, Penner, J. E, Seland, O, Skeie, R. B, Stier, P, Takemura, T, Tsigaridis, K, and Zhang, K
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Meteorology And Climatology - Abstract
The impact of black carbon (BC) aerosols on the global radiation balance is not well constrained. Here twelve global aerosol models are used to show that at least 20% of the present uncertainty in modeled BC direct radiative forcing (RF) is due to diversity in the simulated vertical profile of BC mass. Results are from phases 1 and 2 of the global aerosol model intercomparison project (AeroCom). Additionally, a significant fraction of the variability is shown to come from high altitudes, as, globally, more than 40% of the total BC RF is exerted above 5 km. BC emission regions and areas with transported BC are found to have differing characteristics. These insights into the importance of the vertical profile of BC lead us to suggest that observational studies are needed to better characterize the global distribution of BC, including in the upper troposphere.
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- 2013
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7. Radiative Forcing of the Direct Aerosol Effect from AeroCom Phase II Simulations
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Myhre, G, Samset, B. H, Schulz, M, Balkanski, Y, Bauer, S, Berntsen, T. K, Bian, H, Bellouin, N, Chin, M, Diehl, T, Easter, R. C, Feichter, J, Ghan, S. J, Hauglustaine, D, Iversen, T, Kinne, S, Kirkevag, A, Lamarque, J.-F, Lin, G, Liu, X, Lund, M. T, Luo, G, Ma, X, vanNoije, T, Penner, J. E, Rasch, P. J, Ruiz, A, Seland, O, Skeie, R. B, Stier, P, Takemura, T, Tsigaridis, K, Wang, P, Wang, Z, Xu, L, Yu, H, Yu, F, Yoon, J. -H, Zhang, K, Zhang, H, and Zhou, C
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Meteorology And Climatology - Abstract
We report on the AeroCom Phase II direct aerosol effect (DAE) experiment where 16 detailed global aerosol models have been used to simulate the changes in the aerosol distribution over the industrial era. All 16 models have estimated the radiative forcing (RF) of the anthropogenic DAE, and have taken into account anthropogenic sulphate, black carbon (BC) and organic aerosols (OA) from fossil fuel, biofuel, and biomass burning emissions. In addition several models have simulated the DAE of anthropogenic nitrate and anthropogenic influenced secondary organic aerosols (SOA). The model simulated all-sky RF of the DAE from total anthropogenic aerosols has a range from −0.58 to −0.02 W m(sup−2), with a mean of −0.27 W m(sup−2 for the 16 models. Several models did not include nitrate or SOA and modifying the estimate by accounting for this with information slightly strengthens the mean. Modifying the model estimates for missing aerosol components and for the time period 1750 to 2010 results in a mean RF for the DAE of −0.35 W m(sup−2). Compared to AeroCom Phase I (Schulz et al., 2006) we find very similar spreads in both total DAE and aerosol component RF. However, the RF of the total DAE is stronger negative and RF from BC from fossil fuel and biofuel emissions are stronger positive in the present study than in the previous AeroCom study.We find a tendency for models having a strong (positive) BC RF to also have strong (negative) sulphate or OA RF. This relationship leads to smaller uncertainty in the total RF of the DAE compared to the RF of the sum of the individual aerosol components. The spread in results for the individual aerosol components is substantial, and can be divided into diversities in burden, mass extinction coefficient (MEC), and normalized RF with respect to AOD. We find that these three factors give similar contributions to the spread in results
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- 2013
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8. The Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP): Overview and Description of Models, Simulations and Climate Diagnostics
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Lamarque, J.-F, Shindell, D. T, Naik, V, Plummer, D, Josse, B, Righi, M, Rumbold, S. T, Schulz, M, Skeie, R. B, Strode, S, Young, P. J, Cionni, I, Dalsoren, S, Eyring, V, Bergmann, D, Cameron-Smith, P, Collins, W. J, Doherty, R, Faluvegi, G, Folberth, G, Ghan, S. J, Horowitz, L. W, Lee, Y. H, MacKenzie, I. A, and Nagashima, T
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Meteorology And Climatology - Abstract
The Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP) consists of a series of time slice experiments targeting the long-term changes in atmospheric composition between 1850 and 2100, with the goal of documenting composition changes and the associated radiative forcing. In this overview paper, we introduce the ACCMIP activity, the various simulations performed (with a requested set of 14) and the associated model output. The 16 ACCMIP models have a wide range of horizontal and vertical resolutions, vertical extent, chemistry schemes and interaction with radiation and clouds. While anthropogenic and biomass burning emissions were specified for all time slices in the ACCMIP protocol, it is found that the natural emissions are responsible for a significant range across models, mostly in the case of ozone precursors. The analysis of selected present-day climate diagnostics (precipitation, temperature, specific humidity and zonal wind) reveals biases consistent with state-of-the-art climate models. The model-to- model comparison of changes in temperature, specific humidity and zonal wind between 1850 and 2000 and between 2000 and 2100 indicates mostly consistent results. However, models that are clear outliers are different enough from the other models to significantly affect their simulation of atmospheric chemistry.
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- 2013
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9. Aerosols at the poles: an AeroCom Phase II multi-model evaluation
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Sand, M., Samset, B. H., Balkanski, Y., Bauer, S., Bellouin, N., Berntsen, T. K., Bian, H., Chin, M., Diehl, T., Easter, R., Ghan, S. J., Iversen, T., Kirkevåg, A., Lamarque, J.-F., Lin, G., Liu, X., Luo, G., Myhre, G., Noije, T. V., Penner, J. E., Schulz, M., Seland, Ø., Skeie, R. B., Stier, P., Takemura, T., Tsigaridis, K., Yu, F., Zhang, K., Zhang, H., Center for International Climate and Environmental Research [Oslo] (CICERO), University of Oslo (UiO), Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Modelling the Earth Response to Multiple Anthropogenic Interactions and Dynamics (MERMAID), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Department of Meteorology [Reading], University of Reading (UOR), Joint Center for Earth Systems Technology [Baltimore] (JCET), NASA Goddard Space Flight Center (GSFC)-University of Maryland [Baltimore County] (UMBC), University of Maryland System-University of Maryland System, NASA Goddard Space Flight Center (GSFC), JRC Institute for Environment and Sustainability (IES), European Commission - Joint Research Centre [Ispra] (JRC), Pacific Northwest National Laboratory (PNNL), Atmospheric Chemistry Observations and Modeling Laboratory (ACOML), National Center for Atmospheric Research [Boulder] (NCAR), Norwegian Meteorological Institute [Oslo] (MET), Department of Physics [Oxford], University of Oxford [Oxford], Kyushu University [Fukuoka], Center for Climate Systems Research [New York] (CCSR), Columbia University [New York], Atmospheric Sciences Research Center (ASRC), University at Albany [SUNY], State University of New York (SUNY)-State University of New York (SUNY), University of Maryland [Baltimore County] (UMBC), University of Maryland System-University of Maryland System-NASA Goddard Space Flight Center (GSFC), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), University of Oxford, and Kyushu University
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Earth's energy budget ,Atmospheric Science ,010504 meteorology & atmospheric sciences ,010502 geochemistry & geophysics ,Atmospheric sciences ,7. Clean energy ,01 natural sciences ,Latitude ,lcsh:Chemistry ,chemistry.chemical_compound ,Sea ice ,Sulfate ,Optical depth ,0105 earth and related environmental sciences ,[PHYS.PHYS.PHYS-AO-PH]Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph] ,[SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere ,geography ,geography.geographical_feature_category ,Radiative forcing ,lcsh:QC1-999 ,Aerosol ,lcsh:QD1-999 ,Arctic ,chemistry ,13. Climate action ,Climatology ,Environmental science ,lcsh:Physics - Abstract
International audience; Atmospheric aerosols from anthropogenic and natural sources reach the polar regions through long-range transport and affect the local radiation balance. Such transport is, however, poorly constrained in present-day global climate models, and few multi-model evaluations of polar an-thropogenic aerosol radiative forcing exist. Here we compare the aerosol optical depth (AOD) at 550 nm from simulations with 16 global aerosol models from the AeroCom Phase II model intercomparison project with available observations at both poles. We show that the annual mean multi-model median is representative of the observations in Arctic, but that the intermodel spread is large. We also document the geographical distribution and seasonal cycle of the AOD for the individual aerosol species: black carbon (BC) from fossil fuel and biomass burning, sulfate, organic aerosols (OAs), dust, and sea-salt. For a subset of models that represent nitrate and secondary organic aerosols (SOAs), we document the role of these aerosols at high latitudes. The seasonal dependence of natural and anthropogenic aerosols differs with natural aerosols peaking in winter (sea-salt) and spring (dust), whereas AOD from anthropogenic aerosols peaks in late spring and summer. The models produce a median annual mean AOD of 0.07 in the Arctic (de-fined here as north of 60 • N). The models also predict a noteworthy aerosol transport to the Antarctic (south of 70 • S) with a resulting AOD varying between 0.01 and 0.02. The Published by Copernicus Publications on behalf of the European Geosciences Union. 12198 M. Sand et al.: Aerosols at the poles: an AeroCom Phase II multi-model evaluation models have estimated the shortwave anthropogenic radia-tive forcing contributions to the direct aerosol effect (DAE) associated with BC and OA from fossil fuel and biofuel (FF), sulfate, SOAs, nitrate, and biomass burning from BC and OA emissions combined. The Arctic modelled annual mean DAE is slightly negative (−0.12 W m −2), dominated by a positive BC FF DAE in spring and a negative sulfate DAE in summer. The Antarctic DAE is governed by BC FF. We perform sensitivity experiments with one of the AeroCom models (GISS modelE) to investigate how regional emissions of BC and sulfate and the lifetime of BC influence the Arctic and Antarctic AOD. A doubling of emissions in eastern Asia results in a 33 % increase in Arctic AOD of BC. A doubling of the BC lifetime results in a 39 % increase in Arctic AOD of BC. However, these radical changes still fall within the AeroCom model range.
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- 2017
10. Comparison of aerosol optical properties above clouds between POLDER and AeroCom models over the South East Atlantic Ocean during the fire season
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Peers, F., Bellouin, Nicolas, Waquet, F., Ducos, F., Goloub, P., Mollard, J., Myhre, G., Skeie, R. B., Takemura, T., Tanré, D., Thieuleux, F., Zhang, K., Laboratoire d’Optique Atmosphérique - UMR 8518 (LOA), and Institut national des sciences de l'Univers (INSU - CNRS)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)
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above cloud ,aerosol ,[SDU]Sciences of the Universe [physics] ,POLDER ,absorption ,AeroCom - Abstract
Aerosol properties above clouds have been retrieved over the South East Atlantic Ocean during the fire season 2006 using satellite observations from POLDER (Polarization and Directionality of Earth Reflectances). From June to October, POLDER has observed a mean Above-Cloud Aerosol Optical Thickness (ACAOT) of 0.28 and a mean Above-Clouds Single Scattering Albedo (ACSSA) of 0.87 at 550nm. These results have been used to evaluate the simulation of aerosols above clouds in five Aerosol Comparisons between Observations and Models (Goddard Chemistry Aerosol Radiation and Transport (GOCART), Hadley Centre Global Environmental Model 3 (HadGEM3), European Centre Hamburg Model 5-Hamburg Aerosol Module 2 (ECHAM5-HAM2), Oslo-Chemical Transport Model 2 (OsloCTM2), and Spectral Radiation-Transport Model for Aerosol Species (SPRINTARS)). Most models do not reproduce the observed large aerosol load episodes. The comparison highlights the importance of the injection height and the vertical transport parameterizations to simulate the large ACAOT observed by POLDER. Furthermore, POLDER ACSSA is best reproduced by models with a high imaginary part of black carbon refractive index, in accordance with recent recommendations. ©2016. American Geophysical Union.
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- 2016
11. Evaluating the CLimate and Air Quality ImPacts of Short-livEd Pollutants (ECLIPSE)
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Stohl, A., Aamaas, B., Amann, M., Baker, L.H., Bellouin, N., Berntsen, T.K., Boucher, O., Cherian, R., Collins, W., Daskalakis, N., Dusinska, M., Eck-hardt, S., Fuglestvedt, J. S., Harju, M., Heyes, C., Hodnebrog, Ø., Hao, J., Im, Ulas, Kanakidou, M., Klimont, Z., Kupiainen, K., Law, K. S., Lund, M. T., Maas, R., MacIntosh, C. R., Myhre, G., Myriokefalitakis, S., Olivié, D., Quaas, J., Quennehen, B., Raut, J.-C., Rumbold, S. T., Samset, B.H., Schulz, M., Seland, Ø., Shine, K. P., Skeie, R. B., Wang, S., Yttri, K. E., and Zhu, T.
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- 2015
12. Current model capabilities for simulating black carbon and sulfate concentrations in the Arctic atmosphere: a multi-model evaluation using a comprehensive measurement data set
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Eckhardt, S., Quennehen, B., Olivié, D. J. L., Berntsen, T. K., Cherian, R., Christensen, J. H., Collins, W., Crepinsek, S., Daskalakis, N., Flanner, M., Herber, A., Heyes, C., Hodnebrog, Ø., Huang, L., Kanakidou, M., Klimont, Z., Langner, J., Law, K. S., Lund, M. T., Mahmood, R., Massling, A., Myriokefalitakis, S., Nielsen, I. E., Nøjgaard, J. K., Quaas, J., Quinn, P. K., Raut, J.-C., Rumbold, S. T., Schulz, M., Sharma, S., Skeie, R. B., Skov, H., Uttal, T., von Salzen, K., Stohl, A., Norwegian Institute for Air Research (NILU), TROPO - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Norwegian Meteorological Institute [Oslo] (MET), Center for International Climate and Environmental Research [Oslo] (CICERO), University of Oslo (UiO), Leipziger Institut für Meteorologie (LIM), Universität Leipzig [Leipzig], Department of Environmental Science [Roskilde] (ENVS), Aarhus University [Aarhus], University of Reading (UOR), Met Office Hadley Centre for Climate Change (MOHC), United Kingdom Met Office [Exeter], Cooperative Institute for Research in Environmental Sciences (CIRES), University of Colorado [Boulder]-National Oceanic and Atmospheric Administration (NOAA), NOAA Earth System Research Laboratory (ESRL), National Oceanic and Atmospheric Administration (NOAA), Environmental Chemical Processes Laboratory [Heraklion] (ECPL), Department of Chemistry [Heraklion], University of Crete [Heraklion] (UOC)-University of Crete [Heraklion] (UOC), Department of Atmospheric, Oceanic, and Space Sciences [Ann Arbor] (AOSS), University of Michigan [Ann Arbor], University of Michigan System-University of Michigan System, Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung (AWI), International Institute for Applied Systems Analysis [Laxenburg] (IIASA), Climate Research Division [Toronto], Environment and Climate Change Canada, Swedish Meteorological and Hydrological Institute (SMHI), School of Earth and Ocean Sciences [Victoria] (SEOS), University of Victoria [Canada] (UVIC), COMSATS Institute of Information Technology [Islamabad] (CIIT), Institute of Chemical Engineering Sciences - Hellas [Crete] (ICE-HT), Foundation for Research and Technology - Hellas (FORTH), NOAA Pacific Marine Environmental Laboratory [Seattle] (PMEL), Canadian Centre for Climate Modelling and Analysis (CCCma), and Universität Leipzig
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lcsh:Chemistry ,[PHYS.PHYS.PHYS-AO-PH]Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph] ,Zeppelinobservatoriet ,lcsh:QD1-999 ,[SDE]Environmental Sciences ,Miljövetenskap ,lcsh:Physics ,lcsh:QC1-999 ,Environmental Sciences - Abstract
International audience; The concentrations of sulfate, black carbon (BC) and other aerosols in the Arctic are characterized by high values in late winter and spring (so-called Arctic Haze) and low values in summer. Models have long been struggling to capture this seasonality and especially the high concentrations associated with Arctic Haze. In this study, we evaluate sulfate and BC concentrations from eleven different models driven with the same emission inventory against a comprehensive pan-Arctic measurement data set over a time period of two years (2008–2009). The set of models consisted of one Lagrangian particle dispersion model, four chemistry-transport models (CTMs), one atmospheric chemistry-weather forecast model and five chemistry-climate models (CCMs), of which two were nudged to meteorological analyses and three were running freely. The measurement data set consisted of surface measurements of equivalent BC (eBC) from five stations (Alert, Barrow, Pallas, Tiksi and Zeppelin), elemental carbon (EC) from Station Nord and Alert and aircraft measurements of refractory BC (rBC) from six different campaigns. We find that the models generally captured the measured eBC/rBC and sulfate concentrations quite well, compared to past comparisons. However, the aerosol seasonality at the surface is still too weak in most models. Concentrations of eBC and sulfate averaged over three surface sites are underestimated in winter/spring in all but one model (model means for January-March underestimated by 59 and 37% for BC and sulfate, respectively), whereas concentrations in summer are overestimated in the model mean (by 88 and 44% for July–September), but with over- as well as underestimates present in individual models. The most pronounced eBC underestimates, not included in the above multi-site average, are found for the station Tiksi in Siberia where the measured annual mean eBC concentration is three times higher than the average annual mean for all other stations. This suggests an underestimate of BC sources in Russia in the emission inventory used. Based on the campaign data, biomass burning was identified as another cause of the modelling problems. For sulfate, very large differences were found in the model ensemble, with an apparent anti-correlation between modeled surface concentrations and total atmospheric columns. There is a strong correlation between observed sulfate and eBC concentrations with consistent sulfate/eBC slopes found for all Arctic stations, indicating that the sources contributing to sulfate and BC are similar throughout the Arctic and that the aerosols are internally mixed and undergo similar removal. However, only three models reproduced this finding, whereas sulfate and BC are weakly correlated in the other models. Overall, no class of models (e.g., CTMs, CCMs) performed better than the others and differences are independent of model resolution.
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- 2015
13. Multi-model evaluation of short-lived pollutant distributions over east Asia during summer 2008
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Quennehen, B., primary, Raut, J.-C., additional, Law, K. S., additional, Daskalakis, N., additional, Ancellet, G., additional, Clerbaux, C., additional, Kim, S.-W., additional, Lund, M. T., additional, Myhre, G., additional, Olivié, D. J. L., additional, Safieddine, S., additional, Skeie, R. B., additional, Thomas, J. L., additional, Tsyro, S., additional, Bazureau, A., additional, Bellouin, N., additional, Hu, M., additional, Kanakidou, M., additional, Klimont, Z., additional, Kupiainen, K., additional, Myriokefalitakis, S., additional, Quaas, J., additional, Rumbold, S. T., additional, Schulz, M., additional, Cherian, R., additional, Shimizu, A., additional, Wang, J., additional, Yoon, S.-C., additional, and Zhu, T., additional
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- 2016
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14. Robustness and uncertainties of ensemble modeling of Short-Lived Climate Forcers (SLFCs) over Europe
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Im, U., Nikolaos Daskalakis, Myriokefalitakis, S., Kanakidou, M., Boris Quennehen, Jean-Christophe Raut, Law, Kathy S., Klimont, Z., Kupiainen, K., Heyes, C., Eckhardt, S., Stohl, A., Lund, M. T., Skeie, R. B., Schulz, M., Olivie, D. J. L., Quaas, J., Cherian, R., Cardon, Catherine, Environmental Chemical Processes Laboratory [Heraklion] (ECPL), Department of Chemistry [Heraklion], University of Crete [Heraklion] (UOC)-University of Crete [Heraklion] (UOC), TROPO - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de météorologie physique (LaMP), Centre National de la Recherche Scientifique (CNRS)-Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut national des sciences de l'Univers (INSU - CNRS), International Institute for Applied Systems Analysis [Laxenburg] (IIASA), Norwegian Institute for Air Research (NILU), Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Leipziger Institut für Meteorologie (LIM), Universität Leipzig [Leipzig], Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), and Universität Leipzig
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[PHYS.PHYS.PHYS-AO-PH]Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph] ,[SDE.MCG] Environmental Sciences/Global Changes ,[SDE.MCG]Environmental Sciences/Global Changes ,[PHYS.PHYS.PHYS-AO-PH] Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph] - Published
- 2013
15. What controls the vertical distribution of aerosol? Relationships between process sensitivity in HadGEM3–UKCA and inter-model variation from AeroCom Phase II
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Kipling, Z., primary, Stier, P., additional, Johnson, C. E., additional, Mann, G. W., additional, Bellouin, N., additional, Bauer, S. E., additional, Bergman, T., additional, Chin, M., additional, Diehl, T., additional, Ghan, S. J., additional, Iversen, T., additional, Kirkevåg, A., additional, Kokkola, H., additional, Liu, X., additional, Luo, G., additional, van Noije, T., additional, Pringle, K. J., additional, von Salzen, K., additional, Schulz, M., additional, Seland, Ø., additional, Skeie, R. B., additional, Takemura, T., additional, Tsigaridis, K., additional, and Zhang, K., additional
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- 2015
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16. Supplementary material to "What controls the vertical distribution of aerosol? Relationships between process sensitivity in HadGEM3–UKCA and inter-model variation from AeroCom Phase II"
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Kipling, Z., primary, Stier, P., additional, Johnson, C. E., additional, Mann, G. W., additional, Bellouin, N., additional, Bauer, S. E., additional, Bergman, T., additional, Chin, M., additional, Diehl, T., additional, Ghan, S. J., additional, Iversen, T., additional, Kirkevåg, A., additional, Kokkola, H., additional, Liu, X., additional, Luo, G., additional, van Noije, T., additional, Pringle, K. J., additional, von Salzen, K., additional, Schulz, M., additional, Seland, Ø., additional, Skeie, R. B., additional, Takemura, T., additional, Tsigaridis, K., additional, and Zhang, K., additional
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- 2015
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17. Evaluating the climate and air quality impacts of short-lived pollutants
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Stohl, A., primary, Aamaas, B., additional, Amann, M., additional, Baker, L. H., additional, Bellouin, N., additional, Berntsen, T. K., additional, Boucher, O., additional, Cherian, R., additional, Collins, W., additional, Daskalakis, N., additional, Dusinska, M., additional, Eckhardt, S., additional, Fuglestvedt, J. S., additional, Harju, M., additional, Heyes, C., additional, Hodnebrog, Ø., additional, Hao, J., additional, Im, U., additional, Kanakidou, M., additional, Klimont, Z., additional, Kupiainen, K., additional, Law, K. S., additional, Lund, M. T., additional, Maas, R., additional, MacIntosh, C. R., additional, Myhre, G., additional, Myriokefalitakis, S., additional, Olivié, D., additional, Quaas, J., additional, Quennehen, B., additional, Raut, J.-C., additional, Rumbold, S. T., additional, Samset, B. H., additional, Schulz, M., additional, Seland, Ø., additional, Shine, K. P., additional, Skeie, R. B., additional, Wang, S., additional, Yttri, K. E., additional, and Zhu, T., additional
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- 2015
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18. Multi-model evaluation of short-lived pollutant distributions over East Asia during summer 2008
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Quennehen, B., primary, Raut, J.-C., additional, Law, K. S., additional, Ancellet, G., additional, Clerbaux, C., additional, Kim, S.-W., additional, Lund, M. T., additional, Myhre, G., additional, Olivié, D. J. L., additional, Safieddine, S., additional, Skeie, R. B., additional, Thomas, J. L., additional, Tsyro, S., additional, Bazureau, A., additional, Bellouin, N., additional, Daskalakis, N., additional, Hu, M., additional, Kanakidou, M., additional, Klimont, Z., additional, Kupiainen, K., additional, Myriokefalitakis, S., additional, Quaas, J., additional, Rumbold, S. T., additional, Schulz, M., additional, Cherian, R., additional, Shimizu, A., additional, Wang, J., additional, Yoon, S.-C., additional, and Zhu, T., additional
- Published
- 2015
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19. Current model capabilities for simulating black carbon and sulfate concentrations in the Arctic atmosphere: a multi-model evaluation using a comprehensive measurement data set
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Eckhardt, S., primary, Quennehen, B., additional, Olivié, D. J. L., additional, Berntsen, T. K., additional, Cherian, R., additional, Christensen, J. H., additional, Collins, W., additional, Crepinsek, S., additional, Daskalakis, N., additional, Flanner, M., additional, Herber, A., additional, Heyes, C., additional, Hodnebrog, Ø., additional, Huang, L., additional, Kanakidou, M., additional, Klimont, Z., additional, Langner, J., additional, Law, K. S., additional, Massling, A., additional, Myriokefalitakis, S., additional, Nielsen, I. E., additional, Nøjgaard, J. K., additional, Quaas, J., additional, Quinn, P. K., additional, Raut, J.-C., additional, Rumbold, S. T., additional, Schulz, M., additional, Skeie, R. B., additional, Skov, H., additional, Lund, M. T., additional, Uttal, T., additional, von Salzen, K., additional, Mahmood, R., additional, and Stohl, A., additional
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- 2015
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20. Modelled black carbon radiative forcing and atmospheric lifetime in AeroCom Phase II constrained by aircraft observations
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Samset, B. H., primary, Myhre, G., additional, Herber, A., additional, Kondo, Y., additional, Li, S.-M., additional, Moteki, N., additional, Koike, M., additional, Oshima, N., additional, Schwarz, J. P., additional, Balkanski, Y., additional, Bauer, S. E., additional, Bellouin, N., additional, Berntsen, T. K., additional, Bian, H., additional, Chin, M., additional, Diehl, T., additional, Easter, R. C., additional, Ghan, S. J., additional, Iversen, T., additional, Kirkevåg, A., additional, Lamarque, J.-F., additional, Lin, G., additional, Liu, X., additional, Penner, J. E., additional, Schulz, M., additional, Seland, Ø., additional, Skeie, R. B., additional, Stier, P., additional, Takemura, T., additional, Tsigaridis, K., additional, and Zhang, K., additional
- Published
- 2014
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21. The AeroCom evaluation and intercomparison of organic aerosol in global models
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Tsigaridis, K., primary, Daskalakis, N., additional, Kanakidou, M., additional, Adams, P. J., additional, Artaxo, P., additional, Bahadur, R., additional, Balkanski, Y., additional, Bauer, S. E., additional, Bellouin, N., additional, Benedetti, A., additional, Bergman, T., additional, Berntsen, T. K., additional, Beukes, J. P., additional, Bian, H., additional, Carslaw, K. S., additional, Chin, M., additional, Curci, G., additional, Diehl, T., additional, Easter, R. C., additional, Ghan, S. J., additional, Gong, S. L., additional, Hodzic, A., additional, Hoyle, C. R., additional, Iversen, T., additional, Jathar, S., additional, Jimenez, J. L., additional, Kaiser, J. W., additional, Kirkevåg, A., additional, Koch, D., additional, Kokkola, H., additional, Lee, Y. H, additional, Lin, G., additional, Liu, X., additional, Luo, G., additional, Ma, X., additional, Mann, G. W., additional, Mihalopoulos, N., additional, Morcrette, J.-J., additional, Müller, J.-F., additional, Myhre, G., additional, Myriokefalitakis, S., additional, Ng, N. L., additional, O'Donnell, D., additional, Penner, J. E., additional, Pozzoli, L., additional, Pringle, K. J., additional, Russell, L. M., additional, Schulz, M., additional, Sciare, J., additional, Seland, Ø., additional, Shindell, D. T., additional, Sillman, S., additional, Skeie, R. B., additional, Spracklen, D., additional, Stavrakou, T., additional, Steenrod, S. D., additional, Takemura, T., additional, Tiitta, P., additional, Tilmes, S., additional, Tost, H., additional, van Noije, T., additional, van Zyl, P. G., additional, von Salzen, K., additional, Yu, F., additional, Wang, Z., additional, Zaveri, R. A., additional, Zhang, H., additional, Zhang, K., additional, Zhang, Q., additional, and Zhang, X., additional
- Published
- 2014
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22. A lower and more constrained estimate of climate sensitivity using updated observations and detailed radiative forcing time series
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Skeie, R. B., primary, Berntsen, T., additional, Aldrin, M., additional, Holden, M., additional, and Myhre, G., additional
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- 2014
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23. Supplementary material to "The AeroCom evaluation and intercomparison of organic aerosol in global models"
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Tsigaridis, K., primary, Daskalakis, N., additional, Kanakidou, M., additional, Adams, P. J., additional, Artaxo, P., additional, Bahadur, R., additional, Balkanski, Y., additional, Bauer, S. E., additional, Bellouin, N., additional, Benedetti, A., additional, Bergman, T., additional, Berntsen, T. K., additional, Beukes, J. P., additional, Bian, H., additional, Carslaw, K. S., additional, Chin, M., additional, Curci, G., additional, Diehl, T., additional, Easter, R. C., additional, Ghan, S. J., additional, Gong, S. L., additional, Hodzic, A., additional, Hoyle, C. R., additional, Iversen, T., additional, Jathar, S., additional, Jimenez, J. L., additional, Kaiser, J. W., additional, Kirkevåg, A., additional, Koch, D., additional, Kokkola, H., additional, Lee, Y. H., additional, Lin, G., additional, Liu, X., additional, Luo, G., additional, Ma, X., additional, Mann, G. W., additional, Mihalopoulos, N., additional, Morcrette, J.-J., additional, Müller, J.-F., additional, Myhre, G., additional, Myriokefalitakis, S., additional, Ng, S., additional, O'Donnell, D., additional, Penner, J. E., additional, Pozzoli, L., additional, Pringle, K. J., additional, Russell, L. M., additional, Schulz, M., additional, Sciare, J., additional, Seland, Ø., additional, Shindell, D. T., additional, Sillman, S., additional, Skeie, R. B., additional, Spracklen, D., additional, Stavrakou, T., additional, Steenrod, S. D., additional, Takemura, T., additional, Tiitta, P., additional, Tilmes, S., additional, Tost, H., additional, van Noije, T., additional, van Zyl, P. G., additional, von Salzen, K., additional, Yu, F., additional, Wang, Z., additional, Zaveri, R. A., additional, Zhang, H., additional, Zhang, K., additional, Zhang, Q., additional, and Zhang, X., additional
- Published
- 2014
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24. Elemental carbon measurements in European Arctic snow packs
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Forsström, S., primary, Isaksson, E., additional, Skeie, R. B., additional, Ström, J., additional, Pedersen, C. A., additional, Hudson, S. R., additional, Berntsen, T. K., additional, Lihavainen, H., additional, Godtliebsen, F., additional, and Gerland, S., additional
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- 2013
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25. An AeroCom assessment of black carbon in Arctic snow and sea ice
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Jiao, C., primary, Flanner, M. G., additional, Balkanski, Y., additional, Bauer, S. E., additional, Bellouin, N., additional, Berntsen, T. K., additional, Bian, H., additional, Carslaw, K. S., additional, Chin, M., additional, De Luca, N., additional, Diehl, T., additional, Ghan, S. J., additional, Iversen, T., additional, Kirkevåg, A., additional, Koch, D., additional, Liu, X., additional, Mann, G. W., additional, Penner, J. E., additional, Pitari, G., additional, Schulz, M., additional, Seland, \\O., additional, Skeie, R. B., additional, Steenrod, S. D., additional, Stier, P., additional, Takemura, T., additional, Tsigaridis, K., additional, van Noije, T., additional, Yun, Y., additional, and Zhang, K., additional
- Published
- 2013
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26. A lower and more constrained estimate of climate sensitivity using updated observations and detailed radiative forcing time series
- Author
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Skeie, R. B., primary, Berntsen, T., additional, Aldrin, M., additional, Holden, M., additional, and Myhre, G., additional
- Published
- 2013
- Full Text
- View/download PDF
27. Corrigendum to "Evaluation of preindustrial to present-day black carbon and its albedo forcing from Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP)" published in Atmos. Chem. Phys., 13, 2607–2634, 2013
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Lee, Y. H., primary, Lamarque, J.-F., additional, Flanner, M. G., additional, Jiao, C., additional, Shindell, D. T., additional, Berntsen, T., additional, Bisiaux, M. M., additional, Cao, J., additional, Collins, W. J., additional, Curran, M., additional, Edwards, R., additional, Faluvegi, G., additional, Ghan, S., additional, Horowitz, L. W., additional, McConnell, J. R., additional, Ming, J., additional, Myhre, G., additional, Nagashima, T., additional, Naik, V., additional, Rumbold, S. T., additional, Skeie, R. B., additional, Sudo, K., additional, Takemura, T., additional, Thevenon, F., additional, Xu, B., additional, and Yoon, J.-H., additional
- Published
- 2013
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28. Corrigendum to "Pre-industrial to end 21st century projections of tropospheric ozone from the Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP)" published in Atmos. Chem. Phys., 13, 2063–2090, 2013
- Author
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Young, P. J., primary, Archibald, A. T., additional, Bowman, K. W., additional, Lamarque, J.-F., additional, Naik, V., additional, Stevenson, D. S., additional, Tilmes, S., additional, Voulgarakis, A., additional, Wild, O., additional, Bergmann, D., additional, Cameron-Smith, P., additional, Cionni, I., additional, Collins, W. J., additional, Dalsøren, S. B., additional, Doherty, R. M., additional, Eyring, V., additional, Faluvegi, G., additional, Horowitz, L. W., additional, Josse, B., additional, Lee, Y. H., additional, MacKenzie, I. A., additional, Nagashima, T., additional, Plummer, D. A., additional, Righi, M., additional, Rumbold, S. T., additional, Skeie, R. B., additional, Shindell, D. T., additional, Strode, S. A., additional, Sudo, K., additional, Szopa, S., additional, and Zeng, G., additional
- Published
- 2013
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29. Evaluation of ACCMIP outgoing longwave radiation from tropospheric ozone using TES satellite observations
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Bowman, K. W., primary, Shindell, D. T., additional, Worden, H. M., additional, Lamarque, J.F., additional, Young, P. J., additional, Stevenson, D. S., additional, Qu, Z., additional, de la Torre, M., additional, Bergmann, D., additional, Cameron-Smith, P. J., additional, Collins, W. J., additional, Doherty, R., additional, Dalsøren, S. B., additional, Faluvegi, G., additional, Folberth, G., additional, Horowitz, L. W., additional, Josse, B. M., additional, Lee, Y. H., additional, MacKenzie, I. A., additional, Myhre, G., additional, Nagashima, T., additional, Naik, V., additional, Plummer, D. A., additional, Rumbold, S. T., additional, Skeie, R. B., additional, Strode, S. A., additional, Sudo, K., additional, Szopa, S., additional, Voulgarakis, A., additional, Zeng, G., additional, Kulawik, S. S., additional, Aghedo, A. M., additional, and Worden, J. R., additional
- Published
- 2013
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30. Pre-industrial to end 21st century projections of tropospheric ozone from the Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP)
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Young, P. J., primary, Archibald, A. T., additional, Bowman, K. W., additional, Lamarque, J.-F., additional, Naik, V., additional, Stevenson, D. S., additional, Tilmes, S., additional, Voulgarakis, A., additional, Wild, O., additional, Bergmann, D., additional, Cameron-Smith, P., additional, Cionni, I., additional, Collins, W. J., additional, Dalsøren, S. B., additional, Doherty, R. M., additional, Eyring, V., additional, Faluvegi, G., additional, Horowitz, L. W., additional, Josse, B., additional, Lee, Y. H., additional, MacKenzie, I. A., additional, Nagashima, T., additional, Plummer, D. A., additional, Righi, M., additional, Rumbold, S. T., additional, Skeie, R. B., additional, Shindell, D. T., additional, Strode, S. A., additional, Sudo, K., additional, Szopa, S., additional, and Zeng, G., additional
- Published
- 2013
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31. Supplementary material to "Tropospheric ozone changes, radiative forcing and attribution to emissions in the Atmospheric Chemistry and Climate Model Inter-comparison Project (ACCMIP)"
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Stevenson, D. S., primary, Young, P. J., additional, Naik, V., additional, Lamarque, J.-F., additional, Shindell, D. T., additional, Voulgarakis, A., additional, Skeie, R. B., additional, Dalsoren, S. B., additional, Myhre, G., additional, Berntsen, T. K., additional, Folberth, G. A., additional, Rumbold, S. T., additional, Collins, W. J., additional, MacKenzie, I. A., additional, Doherty, R. M., additional, Zeng, G., additional, van Noije, T. P. C., additional, Strunk, A., additional, Bergmann, D., additional, Cameron-Smith, P., additional, Plummer, D. A., additional, Strode, S. A., additional, Horowitz, L., additional, Lee, Y. H., additional, Szopa, S., additional, Sudo, K., additional, Nagashima, T., additional, Josse, B., additional, Cionni, I., additional, Righi, M., additional, Eyring, V., additional, Conley, A., additional, Bowman, K. W., additional, and Wild, O., additional
- Published
- 2012
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32. Tropospheric ozone changes, radiative forcing and attribution to emissions in the Atmospheric Chemistry and Climate Model Inter-comparison Project (ACCMIP)
- Author
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Stevenson, D. S., primary, Young, P. J., additional, Naik, V., additional, Lamarque, J.-F., additional, Shindell, D. T., additional, Voulgarakis, A., additional, Skeie, R. B., additional, Dalsoren, S. B., additional, Myhre, G., additional, Berntsen, T. K., additional, Folberth, G. A., additional, Rumbold, S. T., additional, Collins, W. J., additional, MacKenzie, I. A., additional, Doherty, R. M., additional, Zeng, G., additional, van Noije, T. P. C., additional, Strunk, A., additional, Bergmann, D., additional, Cameron-Smith, P., additional, Plummer, D. A., additional, Strode, S. A., additional, Horowitz, L., additional, Lee, Y. H., additional, Szopa, S., additional, Sudo, K., additional, Nagashima, T., additional, Josse, B., additional, Cionni, I., additional, Righi, M., additional, Eyring, V., additional, Conley, A., additional, Bowman, K. W., additional, and Wild, O., additional
- Published
- 2012
- Full Text
- View/download PDF
33. Supplementary material to "Radiative forcing of the direct aerosol effect from AeroCom Phase II simulations"
- Author
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Myhre, G., primary, Samset, B. H., additional, Schulz, M., additional, Balkanski, Y., additional, Bauer, S., additional, Berntsen, T. K., additional, Bian, H., additional, Bellouin, N., additional, Chin, M., additional, Diehl, T., additional, Easter, R. C., additional, Feichter, J., additional, Ghan, S. J., additional, Hauglustaine, D., additional, Iversen, T., additional, Kinne, S., additional, Kirkevåg, A., additional, Lamarque, J.-F., additional, Lin, G., additional, Liu, X., additional, Luo, G., additional, Ma, X., additional, Penner, J. E., additional, Rasch, P. J., additional, Seland, Ø., additional, Skeie, R. B., additional, Stier, P., additional, Takemura, T., additional, Tsigaridis, K., additional, Wang, Z., additional, Xu, L., additional, Yu, H., additional, Yu, F., additional, Yoon, J.-H., additional, Zhang, K., additional, Zhang, H., additional, and Zhou, C., additional
- Published
- 2012
- Full Text
- View/download PDF
34. Radiative forcing of the direct aerosol effect from AeroCom Phase II simulations
- Author
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Myhre, G., primary, Samset, B. H., additional, Schulz, M., additional, Balkanski, Y., additional, Bauer, S., additional, Berntsen, T. K., additional, Bian, H., additional, Bellouin, N., additional, Chin, M., additional, Diehl, T., additional, Easter, R. C., additional, Feichter, J., additional, Ghan, S. J., additional, Hauglustaine, D., additional, Iversen, T., additional, Kinne, S., additional, Kirkevåg, A., additional, Lamarque, J.-F., additional, Lin, G., additional, Liu, X., additional, Luo, G., additional, Ma, X., additional, Penner, J. E., additional, Rasch, P. J., additional, Seland, Ø., additional, Skeie, R. B., additional, Stier, P., additional, Takemura, T., additional, Tsigaridis, K., additional, Wang, Z., additional, Xu, L., additional, Yu, H., additional, Yu, F., additional, Yoon, J.-H., additional, Zhang, K., additional, Zhang, H., additional, and Zhou, C., additional
- Published
- 2012
- Full Text
- View/download PDF
35. Supplementary material to "The Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP): overview and description of models, simulations and climate diagnostics"
- Author
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Lamarque, J.-F., primary, Shindell, D. T., additional, Josse, B., additional, Young, P. J., additional, Cionni, I., additional, Eyring, V., additional, Bergmann, D., additional, Cameron-Smith, P., additional, Collins, W. J., additional, Doherty, R., additional, Dalsoren, S., additional, Faluvegi, G., additional, Folberth, G., additional, Ghan, S. J., additional, Horowitz, L. W., additional, Lee, Y. H., additional, MacKenzie, I. A., additional, Nagashima, T., additional, Naik, V., additional, Plummer, D., additional, Righi, M., additional, Rumbold, S., additional, Schulz, M., additional, Skeie, R. B., additional, Stevenson, D. S., additional, Strode, S., additional, Sudo, K., additional, Szopa, S., additional, Voulgarakis, A., additional, and Zeng, G., additional
- Published
- 2012
- Full Text
- View/download PDF
36. The Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP): overview and description of models, simulations and climate diagnostics
- Author
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Lamarque, J.-F., primary, Shindell, D. T., additional, Josse, B., additional, Young, P. J., additional, Cionni, I., additional, Eyring, V., additional, Bergmann, D., additional, Cameron-Smith, P., additional, Collins, W. J., additional, Doherty, R., additional, Dalsoren, S., additional, Faluvegi, G., additional, Folberth, G., additional, Ghan, S. J., additional, Horowitz, L. W., additional, Lee, Y. H., additional, MacKenzie, I. A., additional, Nagashima, T., additional, Naik, V., additional, Plummer, D., additional, Righi, M., additional, Rumbold, S., additional, Schulz, M., additional, Skeie, R. B., additional, Stevenson, D. S., additional, Strode, S., additional, Sudo, K., additional, Szopa, S., additional, Voulgarakis, A., additional, and Zeng, G., additional
- Published
- 2012
- Full Text
- View/download PDF
37. Supplementary material to "Evaluation of preindustrial to present-day black carbon and its albedo forcing from ACCMIP (Atmospheric Chemistry and Climate Model Intercomparison Project)"
- Author
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Lee, Y. H., primary, Lamarque, J.-F., additional, Flanner, M. G., additional, Jiao, C., additional, Shindell, D. T., additional, Berntsen, T., additional, Bisiaux, M. M., additional, Cao, J., additional, Collins, W. J., additional, Curran, M., additional, Edwards, R., additional, Faluvegi, G., additional, Ghan, S., additional, Horowitz, L. W., additional, McConnell, J. R., additional, Myhre, G., additional, Nagashima, T., additional, Naik, V., additional, Rumbold, S. T., additional, Skeie, R. B., additional, Sudo, K., additional, Takemura, T., additional, and Thevenon, F., additional
- Published
- 2012
- Full Text
- View/download PDF
38. Evaluation of preindustrial to present-day black carbon and its albedo forcing from ACCMIP (Atmospheric Chemistry and Climate Model Intercomparison Project)
- Author
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Lee, Y. H., primary, Lamarque, J.-F., additional, Flanner, M. G., additional, Jiao, C., additional, Shindell, D. T., additional, Berntsen, T., additional, Bisiaux, M. M., additional, Cao, J., additional, Collins, W. J., additional, Curran, M., additional, Edwards, R., additional, Faluvegi, G., additional, Ghan, S., additional, Horowitz, L. W., additional, McConnell, J. R., additional, Myhre, G., additional, Nagashima, T., additional, Naik, V., additional, Rumbold, S. T., additional, Skeie, R. B., additional, Sudo, K., additional, Takemura, T., additional, and Thevenon, F., additional
- Published
- 2012
- Full Text
- View/download PDF
39. Supplementary material to "Pre-industrial to end 21st century projections of tropospheric ozone from the Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP)"
- Author
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Young, P. J., primary, Archibald, A. T., additional, Bowman, K. W., additional, Lamarque, J.-F., additional, Naik, V., additional, Stevenson, D. S., additional, Tilmes, S., additional, Voulgarakis, A., additional, Wild, O., additional, Bergmann, D., additional, Cameron-Smith, P., additional, Cionni, I., additional, Collins, W. J., additional, Dalsøren, S. B., additional, Doherty, R. M., additional, Eyring, V., additional, Faluvegi, G., additional, Horowitz, L. W., additional, Josse, B., additional, Lee, Y. H., additional, MacKenzie, I. A., additional, Nagashima, T., additional, Plummer, D. A., additional, Righi, M., additional, Rumbold, S. T., additional, Skeie, R. B., additional, Shindell, D. T., additional, Strode, S. A., additional, Sudo, K., additional, Szopa, S., additional, and Zeng, G., additional
- Published
- 2012
- Full Text
- View/download PDF
40. Pre-industrial to end 21st century projections of tropospheric ozone from the Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP)
- Author
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Young, P. J., primary, Archibald, A. T., additional, Bowman, K. W., additional, Lamarque, J.-F., additional, Naik, V., additional, Stevenson, D. S., additional, Tilmes, S., additional, Voulgarakis, A., additional, Wild, O., additional, Bergmann, D., additional, Cameron-Smith, P., additional, Cionni, I., additional, Collins, W. J., additional, Dalsøren, S. B., additional, Doherty, R. M., additional, Eyring, V., additional, Faluvegi, G., additional, Horowitz, L. W., additional, Josse, B., additional, Lee, Y. H., additional, MacKenzie, I. A., additional, Nagashima, T., additional, Plummer, D. A., additional, Righi, M., additional, Rumbold, S. T., additional, Skeie, R. B., additional, Shindell, D. T., additional, Strode, S. A., additional, Sudo, K., additional, Szopa, S., additional, and Zeng, G., additional
- Published
- 2012
- Full Text
- View/download PDF
41. Anthropogenic radiative forcing time series from pre-industrial times until 2010
- Author
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Skeie, R. B., primary, Berntsen, T. K., additional, Myhre, G., additional, Tanaka, K., additional, Kvalevåg, M. M., additional, and Hoyle, C. R., additional
- Published
- 2011
- Full Text
- View/download PDF
42. Black carbon in the atmosphere and snow, from pre-industrial times until present
- Author
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Skeie, R. B., primary, Berntsen, T., additional, Myhre, G., additional, Pedersen, C. A., additional, Ström, J., additional, Gerland, S., additional, and Ogren, J. A., additional
- Published
- 2011
- Full Text
- View/download PDF
43. Implications of Climate Change on Health Impact of Forest Fires in Europe
- Author
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Mestl, H, primary, Berntsen, T, additional, Myhre, G, additional, and Skeie, R B, additional
- Published
- 2007
- Full Text
- View/download PDF
44. Multi-model evaluation of short-lived pollutant distributions over East Asia during summer 2008.
- Author
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Quennehen, B., Raut, J.-C., Law, K. S., Ancellet, G., Clerbaux, C., Kim, S.-W., Lund, M. T., Myhre, G., Olivié, D. J. L., Safieddine, S., Skeie, R. B., Thomas, J. L., Tsyro, S., Bazureau, A., Bellouin, N., Daskalakis, N., Hu, M., Kanakidou, M., Klimont, Z., and Kupiainen, K.
- Abstract
The ability of six global and one regional model to reproduce distributions of tropospheric ozone and its precursors, as well as aerosols over Asia in summer 2008 is evaluated using satellite and in-situ observations. Whilst ozone precursors (NO
2 and CO) are generally underestimated by the models in the troposphere, surface NO2 concentrations are overestimated, suggesting that emissions of NOx are too high. Ozone integrated columns and vertical profiles are generally well modeled, but the global models face difficulties simulating the ozone gradient at the surface between urban and rural environments, pointing to the need to increase model resolution. The accuracy of simulated aerosol patterns over eastern China and northern India varies between the models, and although most of the models reproduce the observed pollution features over eastern China, significant biases are noted in the magnitude of optical properties (aerosol optical depth, aerosol backscatter). These results have important implications for accurate prediction of pollution episodes affecting air quality and the radiative effects of these short-lived climate pollutants over Asia. [ABSTRACT FROM AUTHOR]- Published
- 2015
- Full Text
- View/download PDF
45. A lower and more constrained estimate of climate sensitivity using updated observations and detailed radiative forcing time series.
- Author
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Skeie, R. B., Berntsen, T., Aldrin, M., Holden, M., and Myhre, G.
- Subjects
- *
CLIMATE sensitivity , *RADIATIVE forcing , *OCEAN temperature , *EFFECT of human beings on weather , *TIME series analysis , *BAYESIAN analysis - Abstract
The equilibrium climate sensitivity (ECS) is constrained based on observed nearsurface temperature change, changes in ocean heat content (OHC) and detailed radiative forcing (RF) time series from pre-industrial times to 2010 for all main anthropogenic and natural forcing mechanism. The RF time series are linked to the observations of OHC and temperature change through an energy balance model and a stochastic model, using a Bayesian approach to estimate the ECS and other unknown parameters from the data. For the net anthropogenic RF the posterior mean in 2010 is 2.1Wm-2 with a 90% credible interval (C.I.) of 1.3 to 2.8Wm-2, excluding present day total aerosol effects (direct+indirect) stronger than -1.7Wm-2. The posterior mean of the ECS is 1.8 °C with 90%C.I. ranging from 0.9 to 3.2°C which is tighter than most previously published estimates. We find that using 3 OHC data sets simultaneously substantially narrows the range in ECS, while using only one set and similar time periods can produce comparable results as previously published estimates including the heavy tail in the probability function. The use of additional 10 yr of data for global mean temperature change and ocean heat content data narrow the probability density function of the ECS. In addition when data only until year 2000 is used the estimated mean of ECS is 20% higher. Explicitly accounting for internal variability widens the 90%C.I. for the ECS by 60 %, while the mean ECS only becomes slightly higher. [ABSTRACT FROM AUTHOR]
- Published
- 2013
- Full Text
- View/download PDF
46. Black carbon vertical profiles strongly affect its radiative forcing uncertainty.
- Author
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Samset, B. H., Myhre, G., Schulz, M., Balkanski, Y., Bauer, S., Berntsen, T. K., Bian, H., Bellouin, N., Diehl, T., Kinne, S., Kirkåvag, A., Lamarque, J.-F., Lin, G., Liu, X., Penner, J., Easter, R. C., Ghan, S. J., Marque, T. Iversen, Seland, Ø, and Skeie, R. B.
- Abstract
The impact of black carbon (BC) aerosols on the global radiation balance is not well constrained. Here twelve global aerosol models are used to show that at least 20% of the present uncertainty in modeled BC direct radiative forcing (RF) is due to diversity in the simulated vertical profile of BC mass. Results are from phases 1 and 2 of the global aerosol model intercomparison project (AeroCom). Additionally, a significant fraction of the variability is shown to come from high altitudes, as, globally, more than 40% of the total BC RF is exerted above 5 km. BC emission regions and areas with transported BC are found to have differing characteristics. These insights into the importance of the vertical profile of BC lead us to suggest that observational studies are needed to better characterize the global distribution of BC, including in the upper troposphere. [ABSTRACT FROM AUTHOR]
- Published
- 2012
- Full Text
- View/download PDF
47. Tropospheric ozone changes, radiative forcing and attribution to emissions in the Atmospheric Chemistry and Climate Model Inter-comparison Project (ACCMIP).
- Author
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Stevenson, D. S., Young, P. J., Naik, V., Lamarque, J.-F., Shindell, D. T., Voulgarakis, A., Skeie, R. B., Dalsoren, S. B., Myhre, G., Berntsen, T. K., Folberth, G. A., Rumbold, S. T., Collins, W. J., MacKenzie, I. A., Doherty, R. M., Zeng, G., van Noije, T. P. C., Strunk, A., Bergmann, D., and Cameron-Smith, P.
- Abstract
Ozone (O
3 ) from 17 atmospheric chemistry models taking part in the Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP) has been used to calculate tropospheric ozone radiative forcings (RFs). We calculate a value for the pre-industrial (1750) to present-day (2010) tropospheric ozone RF of 0.40Wm-2 . The model range of pre-industrial to present-day changes in O3 produces a spread (±1 standard deviation) in RFs of ±17%. Three different radiation schemes were used -- we find differences in RFs between schemes (for the same ozone fields) of ±10%. Applying two different tropopause definitions gives differences in RFs of ±3%. Given additional (unquantified) uncertainties associated with emissions, climate-chemistry interactions and land-use change, we estimate an overall uncertainty of ±30% for the tropospheric ozone RF. Experiments carried out by a subset of six models attribute tropospheric ozone RF to increased emissions of methane (47%), nitrogen oxides (29%), carbon monoxide (15%) and non-methane volatile organic compounds (9%); earlier studies attributed more of the tropospheric ozone RF to methane and less to nitrogen oxides. Normalising RFs to changes in tropospheric column ozone, we find a global mean normalised RF of 0.042Wm-2 DU-1 , a value similar to previous work. Using normalised RFs and future tropospheric column ozone projections we calculate future tropospheric ozone RFs (Wm-2 ; relative to 1850 -- add 0.04Wm-2 to make relative to 1750) for the Representative Concentration Pathways in 2030 (2100) of: RCP2.6: 0.31 (0.16); RCP4.5: 0.38 (0.26); RCP6.0: 0.33 (0.24); and RCP8.5: 0.42 (0.56). Models show some coherent responses of ozone to climate change: decreases in the tropical lower troposphere, associated with increases in water vapour; and increases in the sub-tropical to mid-latitude upper troposphere, associated with increases in lightning and stratosphere-to-troposphere transport. [ABSTRACT FROM AUTHOR]- Published
- 2012
- Full Text
- View/download PDF
48. Evaluation of preindustrial to present-day black carbon and its albedo forcing from ACCMIP (Atmospheric Chemistry and Climate Model Intercomparison Project).
- Author
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Lee, Y. H., Lamarque, J.-F., Flanner, M. G., Jiao, C., Shindell, D. T., Berntsen, T., Bisiaux, M. M., Cao, J., Collins, W. J., Curran, M., Edwards, R., Faluvegi, G., Ghan, S., Horowitz, L. W., McConnell, J. R., Myhre, G., Nagashima, T., Naik, V., Rumbold, S. T., and Skeie, R. B.
- Abstract
As part of the Atmospheric Chemistry and Climate Model Intercomparison Project (AC-CMIP), we evaluate the historical black carbon (BC) aerosols simulated by 8 ACCMIP models against observations including 12 ice core records, long-term surface mass concentrations and recent Arctic BC snowpack measurements. We also estimate BC albedo forcing by performing additional simulations using offline models with prescribed meteorology from 1996-2000. We evaluated the vertical profile of BC snow concentrations from these offline simulations using the recent BC snowpack measurements. Despite using the same BC emissions, the global BC burden differs by approximately a factor of 3 among models due to differences in aerosol removal parameterizations and simulated meteorology: 34 Gg to 103 Gg in 1850 and 82 Gg to 315 Gg in 2000. However, the global BC burden from preindustrial to present-day increases by 2.5-3 times with little variation among models, roughly matching the 2.5-fold increase in total BC emissions during the same period. We find a large divergence among models at both Northern Hemisphere (NH) and Southern Hemisphere (SH) high latitude regions for BC burden and at SH high latitude regions for deposition fluxes. The ACCMIP simulations match the observed BC surface mass concentrations well in Europe and North America except at Jungfraujoch and Ispra. However, the models fail to predict the Arctic BC seasonality due to severe underestimations during winter and spring. The simulated vertically resolved BC snow concentrations are, on average, within a factor of 2-3 of the BC snowpack measurements except for Greenland and the Arctic Ocean. For the ice core evaluation, models tend to capture both the observed temporal trends and the magnitudes well at Greenland sites. However, models fail to predict the decreasing trend of BC depositions/ice-core concentrations from the 1950s to the 1970s in most Tibetan Plateau ice cores. The distinct temporal trend at the Tibetan Plateau ice cores indicates a strong influence from Western Europe, but the modeled BC increases in that period are consistent with the emission changes in Eastern Europe, the Middle East, South and East Asia. At the Alps site, the simulated BC suggests a strong influence from Europe, which agrees with the Alps ice core observations. Models successfully simulate higher BC concentrations observed at Zuoqiupu during the non-monsoon season than monsoon season, but models underpredict BC in both seasons. Despite a large divergence in BC deposition at two Antarctic ice core sites, models are able to capture the relative increase from preindustrial to present-day seen in the ice cores. In 2000 relative to 1850, globally annually averaged BC surface albedo forcing from the offline simulations ranges from 0.014 to 0.019 W m
-2 among the ACCMIP models. Comparing offline and online BC albedo forcings computed by some of the same models, we find that the global annual mean can vary by up to a factor of two because of different aerosol models or different BC-snow parameterizations and snow cover. The spatial distributions of the offline BC albedo forcing in 2000 show especially high BC forcing (i.e. over 0.1 W m-2 ) over Manchuria, Karakoram, and most of the Former USSR. Models predict the highest global annual mean BC forcing in 1980 rather than 2000, mostly driven by the high fossil fuel and biofuel emissions in the Former USSR in 1980. [ABSTRACT FROM AUTHOR]- Published
- 2012
- Full Text
- View/download PDF
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