Tourre Yves Marcel author Columbia University. Lamont-Doherty Earth Observatory Paz Shlomit author Kushnir Yochanan author Columbia University. Lamont-Doherty Earth Observatory White Warren B. author Columbia University. Lamont-Doherty Earth Observatory originator text Articles 2010 English From joint sea surface temperature/sea level pressure (SST/SLP) EOF analyses, lowfrequency variability modes are compared. The multi-decadal oscillation (MDO) changed phases twice during the 20th century, with its north Atlantic SST patterns resembling the Atlantic multi-decadal oscillation (AMO). The quasi-decadal oscillation (QDO) SST patterns displayed a double tripole configuration over the entire Atlantic basin, leading to tropical inter-hemispheric out-of-phase relationship. From the mid-1960s onward, while ST anomalies were negative to the north (negative phases of MDO/AMO), the Sahelian drought persisted with a weaker hurricane power dissipation index (PDI). During that period, the QDO modulated the intensity of the Sahelian drought. Physical oceanography 11 3 180 185 2010 http://dx.doi.org/10.1002/asl.265 http://hdl.handle.net/10022/AC:P:15030 NNC NNC 2012-10-22 11:55:00 -0400 2012-10-22 16:58:25 -0400 9033 eng