Please note that eDoc will be permanently shut down in the first quarter of 2021!      Home News About Us Contact Contributors Disclaimer Privacy Policy Help FAQ

Quick Search
My eDoc
Session History
Support Wiki
Direct access to
document ID:

          Institute: MPI für Meteorologie     Collection: Ocean in the Earth System     Display Documents

ID: 20540.0, MPI für Meteorologie / Ocean in the Earth System
Reconciling two approaches to the detection of anthropogenic influence on climate
Authors:Gillett, N. P.; Hegerl, G. C.; Allen, M. R.; Stott, P. A.; Schnur, Reiner
Date of Publication (YYYY-MM-DD):2002
Title of Journal:Journal of Climate
Journal Abbrev.:J. Clim.
Issue / Number:3
Start Page:326
End Page:329
Review Status:Peer-review
Audience:Not Specified
Abstract / Description:Anthropogenic influences on surface temperature over the second half of the twentieth century are examined using output from two general circulation models (HadCM2 and ECHAM3). Optimal detection techniques involve the comparison of observed temperature changes with those simulated by a climate model, using a control integration to test the null hypothesis that all the observed changes are due to natural variability. Two recent studies have examined the influence of greenhouse gases and the direct effect of sulfate aerosol on surface temperature using output from the same two climate models but with many differences in the methods applied. Both detected overall anthropogenic influence on climate, but results on the separate detection of greenhouse gas and sulfate aerosol influences were different. This paper concludes that the main differences between the results can be explained by the season over which temperatures were averaged, the length of the climatology from which anomalies were taken, and the use of a time-evolving signal pattern as opposed to a spatial pattern of temperature trends. This demonstration of consistency increases confidence in the equivalence of the methodologies in other respects, and helps to synthesize results from the two approaches. Including information on the temporal evolution of the response to different forcings allows sulfate aerosol influence to be detected more easily in HadCM2, whereas focusing on spatial patterns gives better detectability in ECHAM3.
External Publication Status:published
Document Type:Article
Affiliations:MPI für Meteorologie/Physical Climate System/Ocean-Atmosphere Coupling
External Affiliations:Univ Oxford, Dept Phys, Clarendon Lab, Parks Rd, Oxford OX1; 3PU, England; Univ Oxford, Dept Phys, Clarendon Lab, Oxford OX1 3PU, England; Duke Univ, Dept Earth & Ocean Sci, Durham, NC USA; Met Off, Hadley Ctr Climate Predict & Res, Bracknell, Berks, England
The scope and number of records on eDoc is subject to the collection policies defined by each institute - see "info" button in the collection browse view.