Hydrological extremes induced by global warming for transient and stabilized climates

Abstract

This study evaluates whether at identical levels of global warming, extreme precipitation and extreme discharge events are identical for transient and stabilized climates.
Using four Global Circulation Models and a global hydrological model (H08), four extreme-value series were computed on the 0.5 by 0.5 resolution grid, for all land surface. The series were then individually fitted to generalized extreme value (GEV) distributions using the L-moments method.
The statistical behaviors and the GEV distributions fitted to the extreme-value-series revealed that globally, all extreme indices presented large deviations. Differences in extreme indices between the transient and stabilized climates where small but significant while considering the influence of natural variability.
Since differences in extreme indices between the transient and stabilized climate are rather small and only affect a marginal portion of the land surface, relying on only the transient climate for assessing the impact of climate change on extreme events seams acceptable.