 |
| Titel |
Anthropogenic radiative forcing time series from pre-industrial times until 2010 |
| VerfasserIn |
R. B. Skeie, T. K. Berntsen, G. Myhre, K. Tanaka, M. M. Kvalevåg, C. R. Hoyle |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
1680-7316
|
| Digitales Dokument |
URL |
| Erschienen |
In: Atmospheric Chemistry and Physics ; 11, no. 22 ; Nr. 11, no. 22 (2011-11-29), S.11827-11857 |
| Datensatznummer |
250010223
|
| Publikation (Nr.) |
 copernicus.org/acp-11-11827-2011.pdf |
|
|
|
|
|
| Zusammenfassung |
| In order to use knowledge of past climate change to improve our
understanding of the sensitivity of the climate system, detailed knowledge
about the time development of radiative forcing (RF) of the earth atmosphere
system is crucial. In this study, time series of anthropogenic forcing of
climate from pre-industrial times until 2010, for all well established
forcing agents, are estimated. This includes presentation of RF histories of
well mixed greenhouse gases, tropospheric ozone, direct- and indirect
aerosol effects, surface albedo changes, stratospheric ozone and
stratospheric water vapour. For long lived greenhouse gases, standard
methods are used for calculating RF, based on global mean concentration
changes. For short lived climate forcers, detailed chemical transport
modelling and radiative transfer modelling using historical emission
inventories is performed. For the direct aerosol effect, sulphate, black
carbon, organic carbon, nitrate and secondary organic aerosols are
considered. For aerosol indirect effects, time series of both the cloud
lifetime effect and the cloud albedo effect are presented. Radiative forcing
time series due to surface albedo changes are calculated based on prescribed
changes in land use and radiative transfer modelling. For the stratospheric
components, simple scaling methods are used. Long lived greenhouse gases
(LLGHGs) are the most important radiative forcing agent with a RF of
2.83±0.28 W m−2 in year 2010 relative to 1750. The two main aerosol
components contributing to the direct aerosol effect are black carbon and
sulphate, but their contributions are of opposite sign. The total direct
aerosol effect was −0.48±0.32 W m−2 in year 2010. Since
pre-industrial times the positive RF (LLGHGs and tropospheric O3) has
been offset mainly by the direct and indirect aerosol effects, especially in
the second half of the 20th century, which possibly lead to a decrease
in the total anthropogenic RF in the middle of the century. We find a total
anthropogenic RF in year 2010 of 1.4 W m−2. However, the uncertainties
in the negative RF from aerosols are large, especially for the cloud
lifetime effect. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|