To determine the yearly trend terms, the Weibull parameters for each year from 1958 to 2007 are calculated. The linear best-fit functions of the parameters indicate very slight trend terms. For the scale parameter λ, the best-fit function is equation(8) y=0.0004X−0.03,y=0.0004X−0.03,where y   denotes the value of λ, and XX denotes the year (from 1958

to 2007). For the shape parameter k, the best-fit function is equation(9) y=0.0004X+1.447.y=0.0004X+1.447.These trend terms are too small to be considered on a decadal-to-centennial scale, so the yearly-scale trend term of wind strength is assumed to be zero. The cyclical term of wind series can be divided into a long-term (yearly) cyclical term (SL, n) and a short-term (hourly to daily) cyclical term (SL,h). The short-term cyclical term is obtained by calculating the autocorrelation coefficients of hourly wind speed and wind direction series with time lags from CYC202 1 hour to 8760 hours. Results show that the value of the autocorrelation coefficient decreases abruptly from 0.95 to 0.1 in the first 72 hours in both series, and is maintained in the range from –0.1 to 0.1 in lags from 72 to 8760 hours. The loss of correlation within a short time in both

series indicates that there are no short-term cyclical www.selleckchem.com/screening/anti-infection-compound-library.html terms in the wind series. The yearly cyclical term is shown in both class-averaged wind speed series and wind direction series, which indicates similarities of wind series within each class on a yearly scale.

Based on the results of the cyclical terms, each representative wind series can be regarded as an independent series not correlated with the others. With the information on trend and cyclical terms to hand, we can conclude a modelling strategy that the generated representative monthly wind series for each class, which serve as climate inputs for the model, is merely repeated in every cycle of model calculation (each cycle calculates one year’s Lck morphological change) without any trend correction. The same representative wind series are used in the hindcast of the last 300 years as well as the forward projection to the next 300 years. The use of the same wind input conditions in the future projection is based on the IPCC (2007), which indicates that there are no consistent agreements on the future change of average or extreme wind speeds in Europe. Most information about extreme wind events is filtered in the generation of representative wind series, as extreme wind events make up only a small percentage of the whole time period. The statistics of hindcast wind data from 1958 to 2007 indicate that extreme wind events are frequent in the southern Baltic area and may play an important role in reshaping the coastline of the Darss-Zingst peninsula. Normally, the definition of a storm is related to water level variation and wind speeds.

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