Antarctic precipitation: distributed observations during the POPE and AWACA campaigns

Although the deployment of ground-based remote sensing instruments has made possible significant progress, Antarctic precipitation remains poorly understood, in particular away from the scientific stations where most field campaigns have taken place in the past. The PEA Orographic Precipitation Experiment (POPE) campaign took place at the Princess Elisabeth Antarctica station (Queen Maud Land, East Antarctica) during the austral summer 2019-2020. In this framework, a transect of three Doppler vertically profiling precipitation radars (MRR-PRO) was deployed from 20 to 30 km away from the station, in complete autonomy in the complex terrain of the Sor Rondane Mountains. The measurements collected during this campaign highlighted the complex interactions between the terrain and a dry layer likely due to katabatic winds, modulating the occurrence of precipitation in the area.
This POPE campaign also served as a test of the idea of deploying complex instruments dedicated to cloud and precipitation monitoring in complete autonomy to access relevant information away from stations, in areas poorly covered so far. This is a strong motivation for the AWACA project (ERC Synergy), which aims to study the atmospheric branch of the water cycle over Antarctica. AWACA started in September 2021 with the design and construction of autonomous observation platform units (4 in total) sheltering various sensors: surface meteorology, isotopic composition of water vapor and precipitation, and remote sensing of clouds and precipitation. The main deployment along a 1100-km transect between the Dumont d'Urville station at the coast and the Concordia station on the inner Plateau, is scheduled for the austral summer 2024-2025.
In this presentation, I will summarize the main results about precipitation from the POPE campaign as well as the main objectives of the AWACA project.