The interannual variability of the tropical Atlantic Ocean is analyzed with series of altimetric dynamic topography data, sea surface temperatures, and wind stress between Ocotobre 1992 and January 2011 using Empirical Orthogonal Functions and Singular Value Decompositions. Three regions of maximum variability are evidenced: a northern one, between 10 and 20°N, where altimetry, sea surface temperature and wind stress are strongly connected through thermosteric and Ekman pumping effects in 2010 but also in 1998 and in 2005; A southern region, along 20°S, where dynamic topography decreases in 1997 and in 2010 in agreement with surface cooling and southern tradewinds intensification; An equatorial region whose variability appears either as an Est-West slope of the topography and temperature all along the equator (2005 and 2010) or as a (cold) tongue in the Gulf of Guinea (1997 and 2002). Both local wind (meridional component) and western remote (zonal component) effects can be involved in this oceanic triggering. First results of the teleconnections between this tropical Atlantic interannual variability and the tropical Pacific El Ni?o–Southern Oscillation indicate a possible connection of the tropical Atlantic between 10- 20°N with a 19 weeks delay, and in the Gulf of Guinea with a 70-80 weeks one.
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