According to this criterion, 57 storms

occurred in the Darss-Zingst area during 1958–2007, 8 of which were from the east and the rest from the west. Statistical results indicate that January and November can be described as storm months: 31 storms took place in this period. The distribution Selleckchem EPZ5676 of storm directions indicates that WNW is the most probable direction for a storm in this area, with a percentage of 43%. The most probable direction for an easterly storm is NE, with a percentage of 65% in the 8 storms. The annual maximum wind speed profile indicates that storms occur almost every year and that there is no distinct trend in the variation of the storm strength in this 50-year period. Extreme value theory is applied to analyse the storms. The Gumbel distribution is used to calculate the return period of storms. The probability

density function of the Gumbel distribution is equation(10) f(X)=1σexp[μ−Xσ−exp(μ−Xσ)],Where CYC202 supplier σ   is the scale parameter, μ   is the location parameter, and XX is the maximum wind speed of the year. The cumulative distribution function of the Gumbel distribution is given by equation(11) F(X)=exp[−exp(μ−Xσ)].Following a double logarithmic transformation, eq. (11) can be written as equation(12) ln[−lnF(X)]=μ−Xσ. Knowing F  (XX) and XX from the statistics of the annual maximum wind speed, the values of σ and μ can be obtained by least squares fitting using eq. (12). The best-fit Gumbel

distribution of the annual maximum wind speed for the period of 1958–2007 is given by σ = 1.498 and Isotretinoin μ = 20.49. The resultant Gumbel fitting curve is shown in Figure 6a. The return period of the thus given by equation(13) R(X)=11−F(X). The curve of R  (XX) is shown in Figure 6b. Some maximum wind speeds with their return periods and probability of occurrence are listed in Table 3. It is not realistic for the morphodynamic model to include every wind storm with a different return period. According to the distribution of wind storm directions and the frequency of the storms that blew in the research area in the period of 1958–2007, one annual storm from the WNW and a once-every-n-years storm from the NE are included in the model. Here, n is a variable (which should range between 5 and 10 according to the statistical result) that results from correction of the wind-induced wave spectrum aiming at inducing similar coastline change to the measured data. The maximum wind speed is 21.5 m s−1 in both storms and the duration is 48 hours (wind speed above 14 m s−1, according to the definition of a storm), which is the typical duration of a storm in the southern Baltic Sea according to the statistical results of wind storms in 1958–2007. The wind speed is assumed to increase linearly from 14 m s−1 to 21.