Wind persistence in Croatia

On the basis of mean hourly wind direction and wind speed data from 11 anemograph stations in the eastern part of the Adriatic sea and seven inland stations in Croatia, and records of different length, the basic characteristics of wind persistence are discussed. In continuation of our earlier work, which dealt with wind persistence regardless of wind direction, this paper presents the results of investigation on wind persistence for wind groups of three combined directions. On the Adriatic three dominant winds are analysed: Bora, ‘Jugo’, and Etesian winds. The mean run length, run duration for 90 per cent and 95 per cent of all cases, as well as the longest recorded duration for run levels of v ⩽ 3m s −1 , v 3 m s −1 , v > 5 m s −1 , v > 8 m s −1 , v > 12 m s −1 and v > 18 m s −1 , are elaborated. With regard to the potential utilization of wind, the most promising areas regarding wind persistence are the Velebit Channel in the northern Adriatic and the exposed islands in the southern Adriatic. The second part deals with different methods and analytical functions describing wind persistence depending on different parameters that could be assessed on the basis of observed wind runs or by using only the mean annual wind speed. The best results were achieved using the power exponential function, especially for long wind runs. The third part includes the testing of the methods used on the data for the station Sinj, with satisfactory results.