Extreme precipitation vulnerability in the Upper Thames River basin: uncertainty in climate model projections.

This study provides an assessment of possible future climate conditions for the Upper Thames River (UTR) basin. The interpretation of future climate from widely used global climate models has a large impact on the comparison of the simulated daily extreme precipitations. Unfortunately, literature relevant to analyzing precipitation extremes is limited and more work is necessary to develop strategies for assessing the vulnerability of extreme precipitation events on water resources and communities at both local and regional levels. The present study deals with six different atmosphere-ocean coupled general circulation models (AOGCMs) with up to three emission scenarios in order to generate a precipitation series for the 2050s. The data has been downscaled using a principal component analysis-integrated stochastic weather generator (WG-PCA) to produce a synthetic dataset for 54 years. The variability between the AOGCMs and their emission scenarios are investigated, as well as the performance of the WG-PCA generator in producing extreme precipitation events. The comparative analysis of 14 different scenarios shows that the AOGCM results are variable and need to be carefully screened before using them for future climate change impact assessments in the UTR basin. Future work is needed on regional studies to explore local characteristics of precipitation extremes and improve the model quality by introducing more input variables relevant to the precipitation extremes. Copyright © 2010 Royal Meteorological Society [ABSTRACT FROM AUTHOR]