MAXIMUM PRECIPITATION FOR DIFFERENT SHORT-TERM INTERVALS

A time series and extreme value analysis of maximum precipitation for distinct time intervals from 10 minutes to 1 day have been deduced for the observatory Zagreb-Grič (φ{symbol} = 45°49′ and λ = 15°59′, Hs = 157 m) for the period between 1908 and 1985. The Spearman rank correlation test revealed that the short-term precipitation maxima series for the time intervals of 10 to 30 minutes and 8 to 24 hours indicate no significant trend for the 95 percent probability level. The 40-minute to 4-hour precipitation maxima exhibited an increaese in recent time. Annual maximum t-minute precipitation was estimated using the Gumbel distribution for sets of data gradually prolonged with 10-year steps towards the past. The ratios (q) of maximum precipitation estimates for the shorter periods and of estimates for the reference period (1908-1985) have been calculated. Their positions according to the confidence interval on the reference estimates were determined. Confident extreme value estimates could be obtained using at least the 50-60 year data series. © 1990 Springer-Verlag.