Observed solar dimming in the Wider Caribbean

Abstract

We present the results of a study of the dimming-brightening phenomena in the Wider Caribbean. The dataset consisted of time series of global radiation from 30 surface stations covering the period 1961-1990. The stations were distributed over the entire region: three in Florida, USA, five in the Caribbean, three in México 17 Venezuela and one in Honduras. Results showed in general a predominance of the dimming over this period, registered at 20 of the stations, while brightening was only noted at the remaining 10 sites. Associated trends were statistically significant, at 5% level, at 21 of the total 30 stations (70%). In particular 16 of the stations registering dimming and 5 of the ones showing brightening had statistically significant trends. Considering the physico-geographical distribution of the stations they were grouped in continental and insular-peninsular. The significant trends averaged –0.72 Wm^–2 per year for continental stations and –0.82 Wm^–2 per year for the insular-peninsular ones. Dimming was more frequent in continental areas, but more intense in the insular peninsular ones.