Upper-layer ocean heat content variability in the Southern Atlantic from reanalysis data

doi:10.3969/j.issn.1001-909X.2019.03.002

Abstract

Abstract: The South Atlantic Ocean (SAO) connects the North Atlantic, Indian and Southern Oceans. The variability of SAO Ocean Heat Content (OHC) would improve our understandings of the heat redistribution among global ocean basins in a warming climate. In is study, we analyze the spatial and temporal variability of the upper-layer OHC of SAO from European Centre for Medium-Range Weather Forecasts Ocean Reanalysis System 4 data sets and temperature data sets of Institute of Atmospheric Physics of the Chinese Academy of Sciences. Using empirical orthogonal function (EOF) analysis, the OHC of upper 700 m in the Southern Atlantic shows a basin wide warming during the past 60 years. This warming trend is even more apparent and have longer fluctuation cycle with a deeper integration depth for OHC. Correlation analysis shows that leading EOF mode of SAO OHC is dominated by decadal or longer time scale variabilities, with a 9-12 years leading of AMO, suggesting SAO OHC contribute to the North Atlantic climate variation. The SAO OHC-AMO correlation increases with the increased OHC integration depth while SAO OHC-PDO correlation decreases. Besides, it is found that variation of OHC in the whole basin is positively correlated with variation of thermocline depth, and the variation of OHC reflects the dynamical fluctuation in the thermocline.

Key words: Southern Atlantic Ocean, upper layer ocean heat content, spatial and temporal variability, AMO, PDO

CLC Number:

P733.4

DENG Shao-kun, WU Xiang-bai. Upper-layer ocean heat content variability in the Southern Atlantic from reanalysis data[J]. Journal of Marine Sciences, 2019, 37(3): 12-20.

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