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The North Atlantic oscillation (NAO) is a large-scale seesawing movement of atmospheric mass between the North Atlantic subtropical high-pressure system and the Icelandic low-pressure system. This phenomenon has been acknowledged as the dominant mode of winter climate variability in the temperate latitudes of the North Atlantic region. In this study, an attempt is made to identify the effect of the NAO on the rainfall pattern in the Eastern Caribbean, based on data from a representative station in that subregion.Rainfall data taken from a southeastern coastal station in Barbados are used to explore the relationship between the behavior of the NAO (using standardized monthly indexes) and the rainfall pattern at that station. In the period considered , the NAO is shown to have a very significant effect on the monthly variability of rainfall in Barbados during both El Niño and La Niña periods.

This paper analyzes trends of temperatures over Africa and seeks to quantify the most significant processes. Observations of air temperature reveal significant warming trends in the 925-600 hPa layer over tropical west Africa and the east Atlantic. This is related to the influence of desert dust and biomass burning emissions on the atmospheric energy budget. We calculate a net radiative absorption of ∼−20 W m −2 . The southern (northern) plume is rich in short-lived greenhouse gases (dust aerosols), and the atmospheric response, according to a simplified radiative transfer model, is a >3 • C heating of the 2-4 km layer. The observed pattern of warming coincides with a mixture of dust, black carbon and short-lived greenhouse gases in space, time and height. Physical forcing provides a secondary source of regional warming, with sinking motions over the Sahel. The elevated warm layer stabilizes the lower atmosphere over and west of Africa, so drying trends may be anticipated.