Tropical island rainfall : a study of the rainfall distribution of Trinidad, West Indies

Abstract

The study is based upon the concept that climatology cannot be divorced from the dynamics of weather. An attempt is made to outline the meteorological framework of this region of the tropics. The rainfall of Trinidad is then discussed within this framework. The mean annual distribution of rainfall over the island forms a basis for the discussion of monthly distributions. Seasonal variation is pointed out and related to broad scale migrations of the subtropical anticyclones and the equatorial trough. The dual rainfall maximum occurring during the wet season is, in turn, related to the synoptic scale patterns of this season. Distribution is then examined with reference to the moist layer, wind direction and speed. Diurnal distribution is treated in detail and the mechanisms giving rise to the well-defined distribution patterns are discussed. Finally some attention is paid to shower amounts and distribution. In conclusion the rainfall of the island is summarized by relating the seasonal variations to the broadscale meteorological background and the actual distribution to the local scale influences.