This study investigates ocean warming from 1961-2022 using a large ensemble reanalysis system (CIGAR). Results show a 62-year warming of 0.43 ± 0.08 W m⁻², with a statistically significant acceleration of 0.15 ± 0.04 W m⁻² dec⁻¹, peaking at high latitudes. 2022 saw the maximum yearly ocean heat content (OHC) in 11.6% of the global ocean area, nearly double any previous year. Major OHC uncertainty is found in the tropics, with global uncertainty around 40% before and 15% after the mid-2000s. Regional trend uncertainty is largely influenced by observation calibration (high latitudes) and sea surface temperature data uncertainty (low latitudes).

Andrea Storto, Chunxue Yang