Validation of reanalysis Southern Ocean atmosphere trends using sea ice data

• Published in: Atmospheric chemistry and physics Vol. 20; no. 23; pp. 14757 - 14768
• Main Authors: Hobbs, William R, Klekociuk, Andrew R, Pan, Yuhang
• Format: Journal Article
• Language: English
• Published: Katlenburg-Lindau Copernicus GmbH 02-12-2020; Copernicus Publications
• Subjects: Air temperature; Atmosphere; Comparative analysis; Coupling; Data reanalysis; Energy (Physics); Energy budget; Heat; Heat flux; Heat transfer; Ice cover; Oceans; Polar waters; Satellite observation; Sea ice; Sea ice data; Sea ice temperatures; Sea ice trends; Sea level; Sea level pressure; Surface energy; Surface properties; Surface temperature; Surface-air temperature relationships; Temperature trends; Trends; Wind; Southern Ocean; Southern Hemisphere; Antarctica; Antarctic Peninsula
• ISSN: 1680-7324; 1680-7316; 1680-7324
• DOI: 10.5194/acp-20-14757-2020

Reanalysis products are an invaluable tool for representing
variability and long-term trends in regions with limited in situ data, and especially the Antarctic. A comparison of eight different reanalysis products
shows large differences in sea level pressure and surface air temperature trends over the high-latitude Southern Ocean, with implications for studies of the atmosphere's role in driving ocean–sea ice changes. In this study, we use the established close coupling between sea ice cover and surface
temperature to evaluate these reanalysis trends using the independent,
30-year sea ice record from 1980 to 2010. We demonstrate that sea ice trends are a reliable validation tool for most months of the year, although the sea
ice–surface temperature coupling is weakest in summer when the surface energy budget is dominated by atmosphere-to-ocean heat fluxes. Based on our
analysis, we find that surface air temperature trends in JRA55 are most
consistent with satellite-observed sea ice trends over the polar waters of
the Southern Ocean.