Australia: The Land Where Time Began

A biography of the Australian continent 

Atlantic Ocean - Multiple Causes for Equatorial Surface Interannual Temperature Variability

Sea surface temperatures of the eastern equatorial Atlantic Ocean fluctuate interannualy, and these temperature changes lead to climatic changes on the surrounding continents (Carton & Huang, 1994; Carton et al., 1996; Folland et al., 2001). According to the author¹ it is believed the dynamic mechanism underlying variability of Atlantic surface waters is similar to that underlying the El Niño/Southern Oscillation, ENSO, that occurs in the equatorial Pacific Ocean (Zebiak, 1993; Keenlyside & Latif, 2007), with air-sea coupling in both oceans resulting in a positive feedback between, the western basin, surface winds, and in the eastern basin, temperature of the sea surface, and in equatorial regions, heat content of the ocean. In this article the authors¹ reassess the factors that drive this interannual variability, using a suite of observational data, climate reanalysis products and simulations with general circulation models. According to the results of their study not all of the warm events involving wind stress forcing in the equatorial region that have previously been identified can be explained  by ENSO-like dynamics. Their results indicate that a mechanism involving wind forcing just north of the equator induces warm ocean temperature anomalies and these anomalies are subsequently advected towards the equator. The authors¹ conclude that the patterns of surface wind that are associated with anomalies, that are long-lived, of subtropical sea surface temperatures, would indicate a link between Atlantic variability in equatorial and subtropical regions.

Sources & Further reading

1. Richter, Ingo, Swadhin K. Behera, Yukio Masumoto, Bunmei Taguchi, Hideharu Sasaki, and Toshio Yamagata. "Multiple Causes of Interannual Sea Surface Temperature Variability in the Equatorial Atlantic Ocean." Nature Geosci 6, no. 1 (01//print 2013): 43-47.