Time evolution of observed July – September sea surface

6 [1] Using sea surface temperature (SST), precipitation, and atmospheric information, this 7 statistical study revisits the questions of the July–September SST‐Sahel teleconnection 8 variability after removing impact of quasi‐global SSTs over the period 1900–2008. The 9 eastern Mediterranean and the Indian Ocean dominate the relationship, both in terms of 10 intensity and time stability, with significant values in 52% and 47% of years, respectively. 11 More than two thirds of the rainy seasons classified as dry (wet) and 16 out of 18 (12 out 12 of 15) of those classified as very dry (very wet) are concomitant of negative (positive) 13 differences between the Mediterranean and the Indian Ocean. Correlations with the 14 tropical Atlantic, the Niño area, and the western Pacific region are generally lower and less 15 robust, although, in some periods, they can be high with the southern tropical Atlantic. 16 Teleconnection observed with continental precipitation and the 950 hPa moisture flux field 17 confirmed these results. Positive SST differences between the eastern Mediterranean and 18 the Indian Ocean are synchronous of in‐phase rainfall excess over the whole Sudan‐ 19 Sahel due to a strengthening of the convergence between the northeasterly moisture 20 transport from the eastern Mediterranean and the monsoon southwesterly moisture 21 transport from the eastern equatorial Atlantic. This is associated with changes in the 22 atmospheric circulation along the meridional and zonal planes, mainly (1) a subsidence 23 departure from midlevels above 10°N–18°N associated with air ascents above the Saharan 24 thermal lows, (2) upward anomalies on the western and eastern Sahel reinforcing the 25 atmospheric ascents in upper levels, (3) a low‐level subsidence anomaly by 30°E–40°E in 26 agreement with the Indian cooling weakening the normal uplifts, and (4) a reinforcement 27 of the tropical easterly jet over 0°−20°E.