Fig. 2: Temperature, pressure and moisture extremes during the February 2022 hot spell.

Anomalies of a near-surface temperature (°C, shaded) and 500-hPa geopotential height (gpm, contours) and b integrated water vapor (IWV, kg m⁻²) for 7 and 8 February 2022 wrt. summer 1959–2021 over the AP. Thick black line in (a, b) outlines the [55°–78°S; 120–40°W] region used to calculate the analogs based on the 500-hPa geopotential heights (shown in Fig. 10). c–e Percentiles of the 7 and 8 February 2022 anomalies wrt the climatological distribution of 2-day running means (based on 6-hourly values) from summer 1959–2021 for c temperature, d 500-hPa geopotential height, and e IWV. Hatched areas indicate values higher than the 99th percentile, and dots indicate the absolute record values. Thick black line in (c) outlines the [62–70°S 76–55°W] region used to calculate the analog-like temperature anomalies (shown in Fig. 10). White squares indicate the locations of King George Island and Vernadsky. f, g Time series of hourly 2-m air temperature during 1–10 February 2022 for f stations located on King George Island (AWS measurements at Escudero, Frei, Carlini and King Sejong, colored lines) and g Vernadsky station (AWS measurements, purple line) compared to the ERA5 nearest grid-average during the event (bold black), Polar-WRF 1.2-km domain output nearest grid to Carlini (black dash-dot) and King Sejong (black dash), ERA5 climatology (thin black, mean 1959–2021), observed climatology at King Sejong (red, mean 1981–2021) and range based on ERA5 (black dotted line, min/max 1959–2021) and observations at King Sejong (red dotted line, min/max 1989–2021).