Convective and stratiform precipitation events have fundamentally differentphysical causes. Using a radar composite over Germany, this study separatesthese precipitation types and compares extremes at different spatial andtemporal scales, ranging from 1 to 50 km and 5 min to 6 h, respectively.Four main objectives are addressed. First, we investigate extremeprecipitation intensities for convective and stratiform precipitation eventsat different spatial and temporal resolutions to identify type-dependentspace and time reduction factors and to analyze regional and seasonaldifferences over Germany. We find strong differences between the types, withup to 30% higher reduction factors for convective compared to stratiformextremes, exceeding all other observed seasonal and regional differenceswithin one type. Second, we investigate how the differences in reductionfactors affect the contribution of each type to extreme events as a whole,again dependent on the scale and the threshold chosen. A clear shift occurstowards more convective extremes at higher resolution or higher percentiles.For horizontal resolutions of current climate model simulations,i.e., ~10 km, the temporal resolution of the data as well as thechosen threshold have profound influence on which type of extreme will bestatistically dominant. Third, we compare the ratio of area to durationreduction factor for convective and stratiform events and find thatconvective events have lower effective advection velocities than stratiformevents and are therefore more strongly affected by spatial than by temporalaggregation. Finally, we discuss the entire precipitation distributionregarding data aggregation and identify matching pairs of temporal andspatial resolutions where similar distributions are observed. The informationis useful for planning observational networks or storing model data atdifferent temporal and spatial scales.
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