Extreme precipitation events in the Mediterranean area: contrasting two different models for moisture source identification

Abstract. Concern about heavy precipitation events has increasingly grown in the last years southern Europe, especially Mediterranean region. These occasional episodes can result more than 200 mm of rainfall less 24 h, producing flash floods with very high social and economic losses. To better understand these phenomena, a correct identification origin moisture must be found. However, contribution different sources is difficult to estimate from observational data; thus numerical models are usually employed this end. Here, we present comparison between two methodologies for quantification flooding that occurred during October November 1982 western area. A previous study, using online Eulerian Weather Research Forecasting (WRF) Model water vapor tracer (WRF-WVT) model, determined contributions evaporated over four sources: (1) Mediterranean, (2) central (3) North Atlantic Ocean (4) tropical subtropical Africa. In work use offline Lagrangian FLEXPART-WRF model quantify role played by same sources. Considering results provided WRF-WVT as “ground truth”, validated performance FLEXPART-WRF. Results show method an acceptable skill identifying local (western Mediterranean) medium-distance (central Atlantic) remote sources, like areas, underestimated it. Notably, event, area reported relative 6 times lower WRF-WVT. contrast, overestimates some over- underestimates should taken into account other authors when drawing conclusions widely used analysis.