In their contribution to PNAS, Penner et al. (1) used a climate model to estimate the radiative forcing by the aerosol first indirect effect (cloud albedo effect) in two different ways: first, by deriving a statistical relationship between the logarithm of cloud droplet number concentration, ln Nc, and the logarithm of aerosol optical depth, ln AOD (or the logarithm of the aerosol index, ln AI) for present-day and preindustrial aerosol fields,
a method that was applied earlier to satellite data (2), and, second, by computing the radiative flux perturbation between two simulations with and without anthropogenic aerosol sources. They find a radiative forcing that is a factor of 3 lower in the former approach than in the latter [as Penner et al. (1) correctly noted, only their “inline” results are useful for the comparison].
Identifer | oai:union.ndltd.org:DRESDEN/oai:qucosa.de:bsz:15-qucosa-189545 |
Date | 24 November 2015 |
Creators | Quaas, Johannes, Boucher, Olivier, Bellouin, Nicolas, Kinne, Stefan |
Contributors | Universität Leipzig, Institut für Meteorologie, Université Pierre et Marie Curie, Centre National de la Recherche Scientifique, Met Office Hadley Centre,, Max-Planck-Institut für Meteorologie,, National Acadamy of Sciences, |
Publisher | Universitätsbibliothek Leipzig |
Source Sets | Hochschulschriftenserver (HSSS) der SLUB Dresden |
Language | English |
Detected Language | English |
Type | doc-type:article |
Format | application/pdf |
Source | Proceedings of the National Academy of Sciences of the United States of America (2011), 108, 46, E1099 |
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