TEMPORAL AND SPATIAL CHARACTERISTICS OF ANNUAL PRECIPITATION OVER THE BALKANS IN THE 20TH-CENTURY

A study of the annual totals of precipitation is presented for 12 stations in the Balkan area for a period of 92 years (1894–1985) The homogeneity of the precipitation series is examined, and their statistical characteristics are analysed. An abrupt climatic change is found at the station of Belgrad, and a statistically significant trend of annual precipitation is found for various periods for the stations of Kerkyra, Patras, Hvar, and Sarajevo. Persistence is only ascertained for the Belgrad station. The application of principal component analysis has yielded three groups of stations. Group A includes northern and continental stations, group B includes stations of the Ionian and Adriatic Seas, and group C includes the stations of Thessaloniki and Athens. The most important period of fluctuations covers the years 1933–1953, when a humid period is followed by a dry period. The most recent 5‐year period can be described as a very dry one. Finally, comparison between rainfall fluctuations and types of circulation shows that the predominance of meridional circulation over the Balkans results in an increase of precipitation, whilst a zonal circulation results in a decrease of precipitation. Copyright © 1990 John Wiley & Sons, Ltd