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1. Chemical transport model ozone simulations for spring 2001 over the western Pacific: Comparisons with TRACE-P lidar, ozonesondes, and Total Ozone Mapping Spectrometer columns

Author

Wild, Oliver, Sundet, J. K., Prather, M. J., Isaksen, I. S. A., Akimoto, H., Browell, E. V., and Oltmans, S. J.

Subjects
atmospheric chemistry, ozone, photochemistry, troposphere, atmospheric transport, Physical Sciences and Mathematics, marine atmosphere
Abstract

Two closely related chemical transport models (CTMs) employing the same high-resolution meteorological data (∼180 km × ∼180 km × ∼600 m) from the European Centre for Medium-Range Weather Forecasts are used to simulate the ozone total column and tropospheric distribution over the western Pacific region that was explored by the NASA Transport and Chemical Evolution over the Pacific (TRACE-P) measurement campaign in February-April 2001. We make extensive comparisons with ozone measurements from the lidar instrument on the NASA DC-8, with ozonesondes taken during the period around the Pacific Rim, and with TOMS total column ozone. These demonstrate that within the uncertainties of the meteorological data and the constraints of model resolution, the two CTMs (FRSGC/UCI and Oslo CTM2) can simulate the observed tropospheric ozone and do particularly well when realistic stratospheric ozone photochemistry is included. The greatest differences between the models and observations occur in the polluted boundary layer, where problems related to the simplified chemical mechanism and inadequate horizontal resolution are likely to have caused the net overestimation of about 10 ppb mole fraction. In the upper troposphere, the large variability driven by stratospheric intrusions makes agreement very sensitive to the timing of meteorological features. Copyright 2003 by the American Geophysical Union.

Published
2003
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2. Chemical transport model ozone simulations for spring 2001 over the western Pacific:comparisons with TRACE-P lidar, ozonesondes, and Total Ozone Mapping Spectrometer columns

Author

Wild, O, Sundet, J K, Prather, M J, Isaksen, I S A, Akimoto, H, Browell, E V, and Oltmans, S J

Abstract

Two closely related chemical transport models (CTMs) employing the same high-resolution meteorological data (similar to180 km x similar to180 km x similar to600 m) from the European Centre for Medium-Range Weather Forecasts are used to simulate the ozone total column and tropospheric distribution over the western Pacific region that was explored by the NASA Transport and Chemical Evolution over the Pacific (TRACE-P) measurement campaign in February-April 2001. We make extensive comparisons with ozone measurements from the lidar instrument on the NASA DC-8, with ozonesondes taken during the period around the Pacific Rim, and with TOMS total column ozone. These demonstrate that within the uncertainties of the meteorological data and the constraints of model resolution, the two CTMs (FRSGC/UCI and Oslo CTM2) can simulate the observed tropospheric ozone and do particularly well when realistic stratospheric ozone photochemistry is included. The greatest differences between the models and observations occur in the polluted boundary layer, where problems related to the simplified chemical mechanism and inadequate horizontal resolution are likely to have caused the net overestimation of about 10 ppb mole fraction. In the upper troposphere, the large variability driven by stratospheric intrusions makes agreement very sensitive to the timing of meteorological features.

Published
2003
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3. Radiative forcing in the 21st century due to ozone changes in the troposphere and the lower stratosphere

Author

Gauss, M., Myhre, G., Pitari, G., Prather, M. J., Isaksen, I. S. A., Berntsen, T. K., Brasseur, G. P., Dentener, F. J., Richard Derwent, Hauglustaine, D. A., Horowitz, L. W., Jacob, D. J., Johnson, M., Law, K. S., Mickley, L. J., Müller, J. -F, Plantevin, P. -H, Pyle, J. A., Rogers, H. L., Stevenson, D. S., Sundet, J. K., Weele, M., Wild, O., University of Oslo (UiO), Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), 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), Modelling the Earth Response to Multiple Anthropogenic Interactions and Dynamics (MERMAID), 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), 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), and 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)

Subjects
[SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, ozone, radiative forcing, troposphere, stratosphere, Physical Sciences and Mathematics, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, ComputingMilieux_MISCELLANEOUS
Abstract

Radiative forcing due to changes in ozone is expected for the 21st century. An assessment on changes in the tropospheric oxidative state through a model intercomparison ("OxComp'') was conducted for the IPCC Third Assessment Report (IPCC-TAR). OxComp estimated tropospheric changes in ozone and other oxidants during the 21st century based on the "SRES'' A2p emission scenario. In this study we analyze the results of 11 chemical transport models (CTMs) that participated in OxComp and use them as input for detailed radiative forcing calculations. We also address future ozone recovery in the lower stratosphere and its impact on radiative forcing by applying two models that calculate both tropospheric and stratospheric changes. The results of OxComp suggest an increase in global-mean tropospheric ozone between 11.4 and 20.5 DU for the 21st century, representing the model uncertainty range for the A2p scenario. As the A2p scenario constitutes the worst case proposed in IPCC-TAR we consider these results as an upper estimate. The radiative transfer model yields a positive radiative forcing ranging from 0.40 to 0.78 W m(-2) on a global and annual average. The lower stratosphere contributes an additional 7.5-9.3 DU to the calculated increase in the ozone column, increasing radiative forcing by 0.15-0.17 W m(-2). The modeled radiative forcing depends on the height distribution and geographical pattern of predicted ozone changes and shows a distinct seasonal variation. Despite the large variations between the 11 participating models, the calculated range for normalized radiative forcing is within 25%, indicating the ability to scale radiative forcing to global-mean ozone column change.

Published
2003
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4. Fresh air in the 21st century?

Author

Prather, M., Gauss, M., Berntsen, T., Isaksen, I., Sundet, J., Bey, I., Brasseur, G., Dentener, F., Derwent, R., Stevenson, D., Grenfell, L., Hauglustaine, D., Horowitz, L., Jacob, D., Mickley, L., Mark Lawrence, Kuhlmann, R., Muller, J. -F, Pitari, G., Rogers, H., Johnson, M., Pyle, J., Law, K., Weele, M., Wild, O., Department of Earth System Science [Irvine] (ESS), University of California [Irvine] (UC Irvine), University of California (UC)-University of California (UC), Department Geophysics [Oslo], Faculty of Mathematics and Natural Sciences [Oslo], University of Oslo (UiO)-University of Oslo (UiO), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), Max-Planck-Institut für Meteorologie (MPI-M), Max-Planck-Gesellschaft, European Commission - Joint Research Centre [Ispra] (JRC), Met Office Hadley Centre for Climate Change (MOHC), United Kingdom Met Office [Exeter], Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), 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), Modelling the Earth Response to Multiple Anthropogenic Interactions and Dynamics (MERMAID), 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), NOAA Geophysical Fluid Dynamics Laboratory (GFDL), National Oceanic and Atmospheric Administration (NOAA), Department of Earth and Planetary Sciences [Cambridge, USA] (EPS), Harvard University, Max-Planck-Institut für Chemie (MPIC), Belgian Institute for Space Aeronomy / Institut d'Aéronomie Spatiale de Belgique (BIRA-IASB), Dipartimento di Fisica [L'Aquila], Università degli Studi dell'Aquila = University of L'Aquila (UNIVAQ), Centre for Atmospheric Science [Cambridge, UK], University of Cambridge [UK] (CAM), Royal Netherlands Meteorological Institute (KNMI), Frontier Research System for Global Change (FRSGC), Japan Agency for Marine-Earth Science and Technology (JAMSTEC), University of California [Irvine] (UCI), University of California-University of California, 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)-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), Harvard University [Cambridge], and Università degli Studi dell'Aquila (UNIVAQ)

Subjects
[SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, ComputingMilieux_MISCELLANEOUS
Abstract

Ozone is an air quality problem today for much of the world's population. Regions can exceed the ozone air quality standards (AQS) through a combination of local emissions, meteorology favoring pollution episodes, and the clean-air baseline levels of ozone upon which pollution builds. The IPCC 2001 assessment studied a range of global emission scenarios and found that all but one projects increases in global tropospheric ozone during the 21st century. By 2030, near-surface increases over much of the northern hemisphere are estimated to be about 5 ppb (+2 to +7 ppb over the range of scenarios). By 2100 the two more extreme scenarios project baseline ozone increases of >20 ppb, while the other four scenarios give changes of -4 to +10 ppb. Even modest increases in the background abundance of tropospheric ozone might defeat current AQS strategies. The larger increases, however, would gravely threaten both urban and rural air quality over most of the northern hemisphere.

Published
2003
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5. Fresh air in the 21st century?

Author

Prather, Michael, Gauss, M, Berntsen, T, Isaksen, I, Sundet, J, Bey, I, Brasseur, G, Dentener, F, Derwent, R, Stevenson, D, Grenfell, L, Hauglustaine, D, Horowitz, L, Jacob, D, Mickley, L, Lawrence, M, von Kuhlmann, R, Muller, J.-F., Pitari, G, Rogers, H, Johnson, M, van Weele, M, and Wild, O

Subjects
ozone, atmospheric pollution, Physical Sciences and Mathematics, air quality
Abstract

Two sets of sea surface temperature/sea ice changes are used to test the sensitivity of tracer transport to the pattern of warming in the doubled CO2 climate. One set (2CO2WT) has greater tropical and high latitude sea surface temperature changes than the other (2CO2), although both fall within the range of plausible response. Simulations were done both with and without interactive ozone. Results show that the SST pattern affects the circulation change throughout the troposphere and middle atmosphere; the ozone interaction affects primarily the upper stratosphere, but through wave-mean flow interaction has effects that extend down into the upper troposphere. Both experiments feature increased tropospheric/stratospheric exchange at low latitudes and greater vertical mixing within the troposphere; only the WT experiments result in increased interhemispheric transport and a more direct circulation in the high latitude stratosphere. Ozone increases in the upper stratosphere and decreases in the lower stratosphere in all the simulations, with greater transport of high latitude ozone into the troposphere in the WT runs. At sea level there is a more positive phase of the Arctic Oscillation (AO)-type oscillation, and this is also true at 100 mbar, but there is no significance in the middle troposphere and the sign is different in the middle stratosphere. Many of these results differ from those generated in older versions of the GISS GCMAM despite the same SST forcing due to differences in control run characteristics, which has implications for model intercomparison experiments.

Published
2003
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7. Atmospheric Chemistry and Greenhouse Gases

Author

Ehhalt, D., Prather, M., Dentener, F., Derwent, R., Dlugokencky, E., Holland, E., Isaksen, I., Katima, J., Kirchhoff, V., Matson, P., Midgley, P., Wang, M., Berntsen, T., Bey, I., Brasseur, G., Buja, L., Collins, W.J., Daniel, J., DeMore, W.B., Derek, N., Dickerson, R., Etheridge, D., Feichter, J., Fraser, P., Friedl, R., Fuglestvedt, J., Gauss, M., Grenfell, L., Grübler, A., Harris, N., Hauglustaine, D., Horowitz, L., Jackman, C., Jacob, D., Jaeglé, L., Jain, A., Kanakidou, M., Karlsdottir, S., Ko, M., Kurylo, M., Lawrence, M., Logan, J.A., Manning, M., Mauzerall, D., Mcconnell, J., Mickley, L., Montzka, S., Müller, J.F., Olivier, J., Pickering, K., Pitari, G., Roelofs, G.J., Rogers, H., Rognerud, B., Smith, S., Solomon, S., Staehelin, J., Steele, P., Stevenson, D., Sundet, J., Thompson, A., Van Weele, M, Von Kuhlmann, R, Wang, Y., Weisenstein, D., Wigley, T., Wild, O., Wuebbles, D., Yantosca, R., Joos, F, Mcfarland, M, 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), 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 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)

Subjects
[SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, 2 Trace Gases: Current Observations, 2 Atmospheric measurements and modelling of photochemistry 264, 6 Tropospheric OH and Photochemical Modelling 263 4, 1 Non-CO 2 Kyoto Gases 248 4, 1 Laboratory data and the OH lifetime of greenhouse gases 263 4, 1 Methane (CH 4 ) 248 4, 3 Reactive Gases 256 4, 3 Hydrofluorocarbons (HFCs) 253 4, 4 Tropospheric O 3 260 4, 5 Stratospheric H 2 O 263 4, 2 Nitrous oxide (N 2 O) 251 4, 3 Nitrogen oxides (NO x ) 259 4, 2 Montreal Protocol Gases and Stratospheric Ozone (O 3 ) 255 4, 1 Carbon monoxide (CO) and hydrogen (H 2 ) 256 4, Trends and Budgets 248 4, 2 Volatile organic compounds (VOC) 257 4, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, 4 Perfluorocarbons (PFCs) and sulphur hexafluoride (SF 6 ) 254 4, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2001

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