Polarimetric Radar Analysis of PISTON Field Campaign Convective Events

Abstract:

During the 2018 and 2019 PISTON field campaign in the open waters of the West Pacific, a wide variety of convection was sampled by the Colorado State University SEAPOL radar on board the R/V’s Thomas G. Thompson (2018) and Sally Ride (2019). In addition to traditional radar measurements such as reflectivity and radial velocity, the polarimetric capabilities of SEAPOL (unique amongst ship-based radars) allow for further insights into the microphysical properties of storms. Over the course of both cruises, SEAPOL observed convection across a spectrum of sizes and organizations – from small, short-lived, isolated convective cells to organized mesoscale convective systems hundreds of kilometers across with embedded convective lines and features. Through analysis of SEAPOL data, the microphysical evolution of several convective case studies is examined in this research. In particular, the rapid RHI scanning strategy employed during the 2019 cruise is used to analyze the evolution of the vertical structure of storms at a high temporal resolution. Sounding profiles and air-sea flux measurements are also used to examine the local environmental conditions which these storms were observed in. The larger scale context under which storms occurred (i.e. typhoons, monsoon flow) is also considered.