[1] Intraseasonal variability (10-50 days) in the equatorial Atlantic Ocean is analyzed from multiyear (1999)(2000)(2001)(2002)(2003)(2004)(2005) satellite gridded products of sea-level anomalies (SLA) and sea-surface temperature (SST). Two regions with distinct intraseasonal variability have been identified. The first one, west of 10°W, is dominated by westward-propagating anomalies, with maximum values in SLA along 5°N and in SST along 2°N: They occur in boreal summer with periods of 25-50 days and are known to correspond to tropical instability waves (TIWs). We show that TIWs have also a signature, though weaker, south of the equator, especially along 5°S, in SLA. Northern and southern anomalies propagate together westward, being mostly out of phase, suggesting that equatorial wave dynamics is involved in TIWs variability. An SST signature of TIWs is also observed near 2°S, in quadrature with SST anomalies detected in the Northern Hemisphere. The interannual modulations of the TIW signature in SLA and SST are compared and discussed. The second dominant intraseasonal signal is only seen east of 10°W in SST and corresponds to an equatorially trapped variability, confined to the Gulf of Guinea with periods between 10 and 20 days. This signal is present in boreal summer when an intense SST front is observed just north of the equator. Intraseasonal variability with comparable periods is also observed in the meridional wind stress throughout the year. Comparison of SST and meridional wind stress anomalies suggests that the 10-to 20-day variability in SST is forced by the wind stress but seasonally modulated by the presence of the SST front.Citation: Athie, G., and F. Marin (2008), Cross-equatorial structure and temporal modulation of intraseasonal variability at the

Four years (September 2012 to August 2016) of simultaneous current observations across the Yucatan Channel (~21.5°N) and the Straits of Florida (~81°W) have permitted us to investigate the characteristics of the flow through the Gulf of Mexico. The average transport in both channels is 27.6 Sv (1 Sv = 106 m3 s−1), in accordance with previous estimates. At the Straits of Florida section, the transport related to the astronomical tide explains 55% of the observed variance with a mixed semidiurnal/diurnal character, while in the Yucatan Channel tides contribute 82% of the total variance and present a dominant diurnal character. At periods longer than a week the transports in the Yucatan and Florida sections have a correlation of 0.83 without any appreciable lag. The yearly running means of the transport time series in both channels are well correlated (0.98) and present a 3-Sv range variation in the 4 years analyzed. This long-term variability is well related to the convergence of the Sverdrup transport in the North Atlantic between 14.25° and 18.75°N. Using 2 years (July 2014–July 2016) of simultaneous currents observations in the Florida section, the Florida Cable section (~26.7°N), and a section across the Old Bahama Channel (~78.4°W), a mean northward transport of 28.4, 31.1, and 1.6 Sv, respectively, is obtained, implying that only 1.1 Sv is contributed by the Northwest Providence Channel to the mean transport observed at the Cable section during this 2-yr period.