On the use of multiple sensors to characterize the spatial gradients of the vertical structure of rainfall in mountainous regions

Mechanisms of mountain precipitation are not yet well understood. In particular the effects of complex terrain on the modification of microphysical and dynamical processes of large weather systems and on the onset of more localized convective storms are widely unknown. In order to understand those mechanisms, a high-spatial resolution rain gauge network is deployed in the Southern Appalachians since summer 2007. Up to date, this network includes 32 raingauge locations installed from mid- to high-elevation along exposed ridges. Along with continuous raingauge records, intense observation campaigns were conducted in July-August 2008, October-November 2008, and June-July 2009 by deploying two Micro Rain Radars (MRR) providing microphysical observations. The work presented here is two-fold. The first aspect of this study will present an integrated analysis of raingauge records and vertically pointing radars (MRR) with an emphasis on characterizing the diurnal cycle of rainfall, seasonality of precipitation, and ridge-valley gradients in vertical structure of rainfall with a focus on microphysical properties. The second aspect of this work, concerns a comparison of raingauge and vertically pointing radars (MRR) records with TRMM 2A25 precipitation products. A long term (from 6 months to more than two years and depending on the rain gauge installation) systematic statistical analysis is performed in order to quantify differences between ground based and remotely sensed observations for precipitation events at the time of satellite overpass. The presentation will provide a synthesis of data analysis and sensor intercomparison.