Description: Das Projekt "Small-scale variability of the raindrop size distribution" wird/wurde gefördert durch: Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung. Es wird/wurde ausgeführt durch: Ecole Polytechnique Federale de Lausanne (EPF), Institut d'Amenagement des Terres et des Eaux (IATE).Precipitation is of crucial importance for the water cycle and the climate system. It is strongly variable in space and time because of the complex interactions between atmospheric dynamics and cloud microphysics. Remote sensing techniques, and weather radar especially, provide high resolution data over extended areas, enabling appropriate investigation of the strong dynamics of precipitation. But these are indirect measurements, and the accurate understanding and characterization of the small-scale variability of the raindrop size distribution (DSD) is of primary importance for the quantitative interpretation of weather radar measurements in terms of rainfall intensity. The present proposal is a 1-year prolongation of an on-going project with similar objectives, and aims first to experimentally characterize and analyze the DSD variability at small scale and then to develop a stochastic tool to simulate intermittent 2D fields of DSDs in time. A network of 16 disdrometers has been deployed over a typical operational radar pixel (about 1x1 km^2) collecting DSD observations every 30 s. This unique data set will be used to quantify the variability of the DSD (and its moments like rain rate and radar reflectivity), to identify its spatial and temporal structure, and to investigate the links with the microphysical processes involved. Using a geostatistical approach, an existing simulation framework will be further developed and generalized in order to be able to reproduce the intermittent nature of rainfall fields as well as their temporal correlation. Such a simulation framework will be useful to quantitatively investigate the uncertainty associated with radar rain retrieval techniques. The overall project will contribute to improve the understanding of the small-scale dynamics of rainfall and its microstructure, as well as to reduce the uncertainty affecting radar rain-rate estimates.
SupportProgram
Origins: /Bund/UBA/UFORDAT
Tags: Wolkenbildung ? Wolke ? Regen ? Bewölkung ? Messstellennetz ? Radar ? Brunnen ? Fernerkundungsdaten ? Gebäude ? Regenwasser ? Duales System ? Messung ? Ackerland ? Bewässerung ? Größenverteilung ? Regen ? Simulation ? Technik ? Wasserkreislauf ? Verwitterung ? Klima ? Niederschlag ? Fahrradfahren ? Raumstruktur ? Wetter ? Gebiet ? Wasser ? DATENSATZ ? PRAEZIPITATION ? STARK ? BETRACHTUNG ? BESCHREIBUNG ? UNTERSUCHUNG ? VERARBEITEN ? VORSCHLAEGE ? Erlass [Recht] ? GEGENWART ? GEMISCHT ? BESTEHEND ? VORSCHLAG ? Werkzeug ? DAUER ? PROJEKT ? PIXEL ?
License: cc-by-nc-nd/4.0
Language: Englisch/English
Time ranges: 2011-02-01 - 2012-01-31
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