Conditions of intense heat (CCI) as an indicator of bioclimatic extremes in Havana, Cuba

Abstract

In this paper, the extreme conditions by excessive heat in Havana (Cuba) and their interannual, seasonal and intraseasonal variability are characterized. A new bioclimatic index (intense heat condition – IHC) is generated from the thermal sensations of people in contrasting hours (07:00 and 13:00 h – 75º W), according to effective temperature and equivalent effective temperature indexes. The calculations were made for the period 1975-2004, with climatic data from meteorological stations of Casablanca and Santiago de las Vegas and microclimate observations in different points inside the city. The results show that IHC illustrates cohesively so much the mean conditions as the climate variability of the extreme heat, when being compared with other bioclimatic indexes. A contrast in the behaviour of the number of days with IHC is established between the coastal area (higher values) and inland (lower values). Increasing trends of high statistical significance in the number of annual days with IHC; significant points of change in the series between 1980 and 1994; and the enlargement of the season where such conditions were present, more remarkable in Santiago de las Vegas station, are reported. Under IHC in Casablanca, important variations can take place inside the city, where the distance to the sea, the influence of the wind, the construction density, among other factors, seem to be decisive. This approach and methodology can be applied to other natural or political-administrative units, with similar climatic conditions.