Here we present the climate change signals for the wind, for spatial and temporal scales ranging from hemispherical down to once-per-year exceeded local quantities.
Four state-of-the-art IPCC AR4 General Circulation Models (GCMs) do not indicate an increase of the extreme winds averaged over the Northern Hemisphere due to enhanced greenhousegas concentrations, although there are considerable spatial differences. Three of the four analyzed models show similar changes in mean sea level pressure (MSLP) patterns over the Northern Atlantic and Europe, resulting in a more zonal flow over Western Europe. This enhanced zonality is accompanied by once-per-year exceeded wind speeds that are several percents higher. The fourth model shows neither an increase in zonal flow over Western Europe, nor an increase in the annual extreme winds.
For the once-per-year extremes of the extra-tropical daily-mean winds in winter, the GCM results are as good as high-resolution Regional Climate Models (RCMs) nested in their domains, thus enabling to directly use the GCM output for studies for e.g. safety design levels and climate change signals.
Using MSLP as a proxy for the number and intensity of extra-tropical storms may be misleading, as more extreme MSLP do not necessarily correspond with increases in storm intensity.
HW van den Brink, BJJM van den Hurk. Future changes in winter wind-climate over Europe
Status: submitted, Journal: Clim. Dyn., Year: 2007