A new method for estimating maximum wind gust speed with a given return period and a high areal resolution

Abstract We propose a new method for estimating maps of extreme wind gust speed. This method uses observed wind data and maps of general wind climate (GWC). The GWC consists of parameter values for the Weibull distribution of the observed wind speeds in 8 wind sectors and the wind frequencies of these sectors. The proposed method assumes that the maximum annual wind gust speeds have a Gumbel distribution. It consists of two steps. In the first step, the parameters of the Gumbel distribution are estimated using observations at single stations. In the second step, a relationship between the Gumbel parameters and the GWC is derived and applied to maps of the GWC. The GWC permits areal estimates of extreme wind speeds with high horizontal resolution. The resolution is dependent on the resolution of the GWC. A map of the maximum wind gust speeds, for a return period of 50 years, was calculated for the Czech Republic with a horizontal resolution of 100 m using the proposed method and its error was estimated. The results showed that only mean wind speeds and sector frequencies from the GWC are the important parameters for the target area.