THE INFLUENCE OF STORM CHARACTERISTICS AND CATCHMENT CONDITIONS ON EXTREME FLOOD RESPONSE - A CASE-STUDY BASED ON THE BRUE RIVER BASIN, UK

Methods for estimating the magnitude of extreme floods are reviewed. A method which combines a probabilistic storm transposition technique w ith a physically-based distributed rainfall-runoff model is described. Synthetic storms with detailed spatial and temporal distributions are generated and applied to the calibrated model of the Brue river basin , U.K. (area 135 km(2)). The variability of catchment response due to storm characteristics (storm area, storm duration, storm movement, sto rm shape and within storm variation) and initial catchment wetness con ditions is investigated. A probabilistic approach to estimating the re turn periods of extreme catchment responses is suggested.