Articolo in rivista, 2024, ENG, 10.1038/s41467-024-44749-7

Acceleration of the ocean warming from 1961 to 2022 unveiled by large-ensemble reanalyses

Storto, Andrea; Yang, Chunxue

Consiglio Nazionale delle Ricerche

Long-term changes in ocean heat content (OHC) represent a fundamental global warming indicator and are mostly caused by anthropogenic climate-altering gas emissions. OHC increases heavily threaten the marine environment, therefore, reconstructing OHC before the well-instrumented period (i.e., before the Argo floats deployment in the mid-2000s) is crucial to understanding the multi-decadal climate change in the ocean. Here, we shed light on ocean warming and its uncertainty for the 1961-2022 period through a large ensemble reanalysis system that spans the major sources of uncertainties. Results indicate a 62-year warming of 0.43 ± 0.08 W m, and a statistically significant acceleration rate equal to 0.15 ± 0.04 W m dec, locally peaking at high latitudes. The 11.6% of the global ocean area reaches the maximum yearly OHC in 2022, almost doubling any previous year. At the regional scale, major OHC uncertainty is found in the Tropics; at the global scale, the uncertainty represents about 40% and 15% of the OHC variability, respectively before and after the mid-2000s. The uncertainty of regional trends is mostly affected by observation calibration (especially at high latitudes), and sea surface temperature data uncertainty (especially at low latitudes).

Nature communications 15 (1)

Keywords

reanalysis, ocean warming

CNR authors

Yang Chunxue, Storto Andrea

CNR institutes

ISMAR – Istituto di scienze marine