OS Ocean Science OS Ocean Sci. 1812-0792 Copernicus Publications Göttingen, Germany 10.5194/os-7-755-2011 An empirical stochastic model of sea-surface temperatures and surface winds over the Southern Ocean Kravtsov S. 1 Kondrashov D. 2 Kamenkovich I. 3 Ghil M. 2 4 University of Wisconsin-Milwaukee, Dept. of Mathematical Sciences, Atmospheric Science group, P.O. Box 413, Milwaukee, WI 53201, USA University of California at Los Angeles, USA University of Miami, USA Ecole Normale Supérieure, Paris, France 14 11 2011 7 6 755 770 Copyright: © 2011 S. Kravtsov et al. 2011 This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/3.0/ This article is available from https://os.copernicus.org/articles/7/755/2011/os-7-755-2011.html The full text article is available as a PDF file from https://os.copernicus.org/articles/7/755/2011/os-7-755-2011.pdf

This study employs NASA's recent satellite measurements of sea-surface temperatures (SSTs) and sea-level winds (SLWs) with missing data filled-in by Singular Spectrum Analysis (SSA), to construct empirical models that capture both intrinsic and SST-dependent aspects of SLW variability. The model construction methodology uses a number of algorithmic innovations that are essential in providing stable estimates of the model's propagator. The best model tested herein is able to faithfully represent the time scales and spatial patterns of anomalies associated with a number of distinct processes. These processes range from the daily synoptic variability to interannual signals presumably associated with oceanic or coupled dynamics. Comparing the simulations of an SLW model forced by the observed SST anomalies with the simulations of an SLW-only model provides preliminary evidence for the ocean driving the atmosphere in the Southern Ocean region.

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