Rights statement: Copyright 2003 by the American Geophysical Union
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Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
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TY - JOUR
T1 - Radiative forcing in the 21st century due to ozone changes in the troposphere and the lower stratosphere
AU - Gauss, M
AU - Myhre, G
AU - Pitari, G
AU - Prather, M J
AU - Isaksen, I S A
AU - Berntsen, T K
AU - Brasseur, G P
AU - Dentener, F J
AU - Derwent, R G
AU - Hauglustaine, D A
AU - Horowitz, L W
AU - Jacob, D J
AU - Johnson, M
AU - Law, K S
AU - Mickley, L J
AU - Muller, J F
AU - Plantevin, P H
AU - Pyle, J A
AU - Rogers, H L
AU - Stevenson, D S
AU - Sundet, J K
AU - van Weele, M
AU - Wild, O
PY - 2003/5/13
Y1 - 2003/5/13
N2 - 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.
AB - 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.
KW - CHEMICAL-TRANSPORT MODEL
KW - GENERAL-CIRCULATION MODEL
KW - SEMI-LAGRANGIAN TRANSPORT
KW - AIRCRAFT MOZAIC DATA
KW - TRACER TRANSPORT
KW - ATMOSPHERIC TRANSPORT
KW - 3-DIMENSIONAL MODEL
KW - PHOTOCHEMICAL MODEL
KW - GLOBAL TROPOSPHERE
KW - NITROGEN-OXIDES
U2 - 10.1029/2002JD002624
DO - 10.1029/2002JD002624
M3 - Journal article
VL - 108
SP - -
JO - Journal of Geophysical Research: Atmospheres
JF - Journal of Geophysical Research: Atmospheres
SN - 0747-7309
IS - D9
M1 - 4292
ER -