Development of a Virga Detection Tool and Associated Study of Arctic Virga and Precipitation

Abstract

Virga is a meteorological phenomenon in which precipitation does not reach the ground due to evaporation or sublimation well above the surface. This significantly influences Earth's energy budget, weather forecasting, climate prediction, hydrology, civilization, and vegetation. Despite its importance, studies of virga and it's quantification are rare and limited due to the lack of observations. This study proposes a novel virga detection tool using the reflectivity (Ze) and Doppler velocity (W) profiles of the vertically pointing Micro Rain Radar (MRR). The method incorporates height and season dependent thresholds and validates outcomes with ground-based disdrometer observations, ensuring reliability and robustness. The detection tool was tested in Ny-Ålesund, a rapidly warming place in the Arctic region where virga studies are limited. The results indicate that the occurrence of virga varies between 25% and 40% between seasons, with evaporation occurring at lower heights in the cold season compared to summer. Virga is often observed before precipitation and leads to a dryer surface condition. The use of the proposed tool is expected to improve the accurate estimation of precipitation and better understanding of the virga process. © 2026. American Geophysical Union. All Rights Reserved.