Variability of biothermal conditions in the vicinity of the Polish Antarctic station in the South Shetlands, West Antarctica

Abstract

There are nine year-round and 11 seasonal scientific stations in the South Shetland Islands, an area often visited by cruise ships and sailing yachts. Although this is the warmest part of Antarctica, the weather conditions may be demanding for humans. We analysed the variability of biothermal conditions near Henryk Arctowski Station Polish Antarctic Station, on King George Island, during the period 2013–2021, using the wind chill index (WCI), which combines air temperature and wind speed, to determine thermal sensation. WCI values were interpreted using two cold sensation categorisations. Hourly WCI values were assigned to thermal sensation classes that ranged from “comfortable” to “frosty.” The most favourable biothermal conditions occurred from December to February. The “cold” sensation was dominant in all months, its average occurrence frequency ranging from 56.4% (in January) to 84.4% (in July). From November to March, there was no risk of frostbite to uncovered body parts. Such conditions occurred only from April to October, with a frequency of 0.2–6.8%; biothermal conditions were also the most variable in this period. Maximal WCI hourly values show that dangerous weather conditions may occur throughout the day in June and for most of the day from July to September. An abrupt change in biothermal conditions was more often caused by wind speed change than by air temperature change. The most marked WCI changes occurred from April to September, on average five times per year. Our results indicate that biothermal conditions in the vicinity of Arctowski Station are predominantly favourable for outdoor work only if a person wears proper winter clothing.