State of polar climate (2024)

The year 2024 has become the warmest year on record globally. As key indicators of global warming, the Antarctic and Arctic have shown heightened sensitivity and experienced more frequent climate anomalies. In this study, using various observations, reanalysis CMA-RA and remote sensing data, we reported detailed 2024 polar climate changes, including air and sea surface warming, sea ice, atmospheric composition and extreme events. In 2024, the air temperature of the Antarctic continent (–31.79 °C) from CMA-RA was slightly higher than the 1991–2020 average, with strong differences between the eastern and western regions and distinct seasonal variations. A persistent warm event occurred in Queen Maud Land, while Wilkes Land remained continuously cold. The inland Dome and Victoria Land showed a ‘cold summers and warm winters’ pattern. The average winter temperature anomaly at Vostok station (+4.34 °C) set a new historical record. The Arctic region continued its warming trend (–6.89 °C, on annual average), with the Canadian Arctic experiencing persistent extreme warmth in CMA-RA. CMA-RA shows that the warming rate in the Arctic (0.52°C per decade, p < 0.01) was 2.9 times the global average since 1979. In August 2024, the Barents Sea surface temperature reached a record high, while the Chukchi Sea reached a record low. The Antarctic sea ice extent remained historically low in 2024, and both the Antarctic and Arctic set new records for sea ice melt. The minimum extent of Antarctic sea ice was 1.97 × 10 6 km 2 (on 20 February), the third lowest on record. The sea ice extent in November set a 46-year low for that month since 1979. The minimum extent (4.21 × 10 6 km 2 ) of Arctic sea ice in 2024 ranked seventh lowest in history. The development of the Antarctic ozone hole in 2024 was relatively stable, showing some alleviation in the previous four years. In the Arctic region, the weakened polar vortex led to an abnormal increase in ozone. The concentrations of greenhouse gases in the polar atmosphere show a similar trend to global changes, all showing a stable upward trend. This investigation and summary of the 2024 polar climate status will help people better understand global and polar climate change.