Summary:

The paper presents an attempt to evaluate rainfall in the context of expected climate changes for the purposeof irrigating. Total precipitation for a chosen meteorological station in Central Poland was simulated for current and expected conditions according by means of GISS Model E, HadCM3 and GFDL R15 scenarios (doubling the CO2 concentration is assumed as typical for Poland and it is expected for years 2050-2060). Four 500-year daily rainfall series were com-pared among themselves so as to analyse the crucial irrigating periods from May to September. For simulated data probability density function of total rainfall were estimated in examined periods, and next used for tail area approximation. The presented results show changes of average sums of rainfall (a 30 per cent drop) in the considered periods and scenario, as well as much greater vari-ance (a 20-per cent increase). In the context of irrigation it implies a greater risk of drought and shows the need for ensuring water requirements for plants in critical periods.The results stress the need for using the comprehensive model taking en bloc meteorological variables into account.