Extreme Rainfall Events in Lund 1979–1980

Abstract

All raingauge measurements give only one-point values. Since the practical applications of rain data always deal with areal measures, the knowledge of areal distribution of rain is very important for correct evaluation of the rain volumes. Two types of rainfall input data are generally used: design rainfall hyetographs and long historical rainfall records. The third type of input data has to be recognized: the observed single rainfall event, during which the consequences such as runoff, flooding or pollution loads have been observed and recorded. Good areal characterization of such single event is necessary if the results are to be generalized. In the paper a set of extreme rainfall events observed in Lund during a period of two years is presented. Point and areal intensities are presented for ten extreme events. Storm centered Areal Reduction Factors (AFR-s) calculated for different durations are also presented. Size, shape and movement of the raincells is discussed in the context of the meteorological background observed.