Observations, Analysis and Modeling of Lightning Activity in Thunderstorms, for use in

- Flash floods are a serious problem in the Mediterranean region in particular, and in Europe in general. These floodsresult from large weather systems with embedded severe thunderstorms that deposit large amounts of rainfall in shortperiods of time. Since lightning activity can be detected and monitored continuously from thousands of kilometers away,we propose the use of lightning data to better nowcast (3-hour prediction) and forecast (24-48 hour prediction) thelocation, intensity and timing of heavy convective precipitation events. For this we plan to develop rainfall-lightning relationships using lightning and precipitation data sets in the Mediterranean region, and to use lightning information in conjunction with infrared / microwave observations from geostationary / low Earth orbiting satellites to improve cloud characterization, convection detection and precipitation retrieval from space.

- With the help of cloud and meso-scale models we plan to simulate numerous cases studies of past flash flood events in Europe to better understand the connection between intense precipitation and lightning activity. Once we have established a methodology to use lightning to help estimate rainfall location and intensity, we plan to develop algorithms for short-term nowcasting, to allow for the short-term flash flood warnings via the internet for the entire Mediterranean region, and perhaps later Europe. Furthermore, using assimilated lightning data in mesoscale meteorological models we plan to investigate the possibility of improving the 24-48 hour forecasts of severe precipitation events. We will validate the new rainfall retrieval algorithms as well as the nowcasting algorithms and forecasting procedures by means of radar and raingauge measurements at several locations across the Mediterranean. The societal benefits of such advanced warnings will be investigated, especially in relation to risk management.