How natural and anthropogenic influences alter global and regional surface temperatures: 1889 to 2006
Article first published online: 16 SEP 2008
Copyright 2008 by the American Geophysical Union.
Geophysical Research Letters
Volume 35, Issue 18, September 2008
How to Cite
2008), How natural and anthropogenic influences alter global and regional surface temperatures: 1889 to 2006, Geophys. Res. Lett., 35, L18701, doi:10.1029/2008GL034864., and (
- Issue published online: 16 SEP 2008
- Article first published online: 16 SEP 2008
- Manuscript Accepted: 8 AUG 2008
- Manuscript Revised: 1 AUG 2008
- Manuscript Received: 2 JUN 2008
- surface temperature;
- natural forcing;
- anthropogenic forcing
 To distinguish between simultaneous natural and anthropogenic impacts on surface temperature, regionally as well as globally, we perform a robust multivariate analysis using the best available estimates of each together with the observed surface temperature record from 1889 to 2006. The results enable us to compare, for the first time from observations, the geographical distributions of responses to individual influences consistent with their global impacts. We find a response to solar forcing quite different from that reported in several papers published recently in this journal, and zonally averaged responses to both natural and anthropogenic forcings that differ distinctly from those indicated by the Intergovernmental Panel on Climate Change, whose conclusions depended on model simulations. Anthropogenic warming estimated directly from the historical observations is more pronounced between 45°S and 50°N than at higher latitudes whereas the model-simulated trends have minimum values in the tropics and increase steadily from 30 to 70°N.