New project –Turbulence and Supercool Clouds in Antarctica (T-SCAN) – to begin January 2025

A new project - Turbulence and Supercool Clouds in Antarctica (T-SCAN) - is funded by the National Weather Service of Argentina (SMN), the Argentine Antarctic Institute (IAA), and the Institute of Polar Science (ISP) within Italy’s National Research Council. T-SCAN will study supercool clouds and the role of turbulence using in-situ measurements across the Antarctic Peninsula and is set to begin 15 January 2025.

T-SCAN will be run by Dr. Paola Rodriguez Imazio from SMN and who is a PCAPS steering group member. T-SCAN is a local and more specific continuation of the Year of Polar Prediction in the Southern Hemisphere (YOPPSH), boosted by knowledge on new measurement techniques, new in-situ data post-processing, and coordination efforts with Adriana Gulisano from the IAA and Vito Vitale from ISP / CNR across the Antarctic Peninsula.

T-SCAN will occur during the austral summer of 2025, where the latest generation of supercooled liquid water content (SLWC) probes will be added to 30 flights outfitted with standard Väisälä radiosondes and will be launched daily from the Argentinian base Marambio, located north of the Antarctic Peninsula. Ground-based devices such as lidar ceilometers, a two-channel microwave radiometer, and an open sky camera will be used to determine cloud-environment related parameters, such as cloud phase, cloud base height, liquid water path (LWP) and precipitable water vapor (PWV).

Location of Marambio. Adapted from: Australian Antarctic Data Centre

The work conducted during T-SCAN will help to significantly improve our understanding of cloud processes in the Antarctic region. The phase of clouds (e.g., supercooled cloud droplets or ice crystals) is a major problem in cloud microphysical parametrisation in climate models. More specifically, the importance of identifying supercooled clouds (SC) droplets in polar regions is essential, since they exert substantial radiative impacts on the surface energy budget and therefore play an important role in Arctic amplification and solar absorption over the Southern Ocean.

Video from Marambio fieldwork. Video credits: Paola Rodriquez Imazio

On shorter time scales, the formation of SC drops generates in-flight icing, which poses a significant hazard to all types of aircraft. SC droplet detection is a high priority for Argentina’s Federal Aviation Administration. Due to the lack of observations of SC droplets, their identification is essential for both aviation and climate research. However, the complex coupling between turbulent fluid dynamics and micro-physical processes, in addition to the scarcity of measurements, currently yields an inadequate representation of cloud processes.

When considering Antarctica, the complexity of measurements is increased due to, but not limited to, extreme weather conditions, difficulties in equipment transportation and maintenance, and lack of suitable calibration. In addition, there is a substantial difference between the number of cloud related studies in the Arctic and Antarctica. This poses challenges for understanding the Antarctic context, given that it is unlikely that results from the Arctic are translatable to the Southern Ocean and coastal Antarctic region due to differences in aerosol concentrations, meteorology, and surface forcing.

Recently, The YOPP-SH, the flagship activity of the Polar Prediction Project within the WMO WWRP, was a major and successful effort to shorten this disparity. During this campaign, international collaboration of academia with meteorological and hydrological services achieved a milestone, when performing a large set of coordinated in-situ and remote measurements, along with numerical studies, which enabled both advanced fundamental knowledge and predictability across Antarctica and the Southern Ocean.

Collaboration efforts between scientists and operators of SMN, IAA and ISP during YOPP-SH, and further analysis of the SLWC data acquired across the Antarctic Peninsula lead to T-SCAN project, driven by the finding of novel results, knowledge on latest technology equipment, and the birth of a new and vibrant group of colleagues across the institutions.

T-SCAN also partners with other institutions in Argentina, such as Universidad de Buenos Aires (UBA) and FLiP (Faculty of Exact and Natural Sciences, UBA).