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Abstract

Co-existence of ice and liquid clouds plays an important role in the cloud life cycle, as well as in precipitation formation and radiative balance. According to satellite observations, coastal regions show the most important proportion of supercooled liquid water (SLW) content in mixed-phase clouds (20-60%), while in the interior this proportion decreases significantly, up to less than 10% in the high Antarctic Plateau (Listowski, et al., 2019). This study is based on two field campaigns on King George Island, northern Antarctic Peninsula, at Escudero station (Portuguese Polar Program projects TULIP/APMAR, February 2022) and King Sejong station (APMAR2 project, February 2023). We present the results of the measurements of SLW content using a new instrument, the universal water content (UWC) sensor, capable to measure both the total and supercooled liquid water content in clouds, by using two vibrating wires sensible to the liquid droplets. We combine the UWC measurements with vertical profiles of tropospheric clouds using a mini-pulse lidar (data provided via MPLnet network) and a vertically-pointing micro rain radar (MRR-2 at Escudero, and a higher vertical resolution MRR-Pro at King Sejong), radiosonde measurements and ERA5 reanalysis data to characterize the tropospheric thermodynamic structure, the melting layer and the precipitation phase transitions. During preliminary case studies, ERA5 specific liquid cloud content vertical profiles showed an agreement with the UWC sensor in the detection of liquid water layers below 2 km altitude, however ERA5 still presents problems to represent the presence of liquid layer clouds at higher altitudes.