THE FORMATION OF THE PRECIPITATION BASED ON THE LONG TIME SERIES OF THE METEOROLOGICAL OBSERVATION OF KESZTHELY

Almost all of the meteorological elements have influence on the success of the agricultural cultivation, but in Hungary among all of these elements precipitation is the most capricious one. The aim of our research is to detect the changes in the 130-year-long time series of precipitation. The precipitation at Keszthely shows a not significant decreasing trend of 42 mm less rainfall in a 100 year long period. The seasonal amounts of rainfall -except for winter- are decreasing. The significantly reduced amount of spring is an unfavorable factor for agriculture. The usual secondary maximum of the yearly precipitation in the autumn at Keszthely seems to vanish. Our farmers must count on at least one period of more than 15 days without rainfall, or two dry periods of 10-14 days length in a vegetation period.