Avaliação diária das características do vapor d'água atmosférico sobre o NE do Brasil.

Abstract

Northeast Brazil is subject to three main rainfall regimes: its northern part ("regime - 3") has a maximum in March, the eastern part has a maximum centered around May-June while in the southern part the maximum occurs in December . Monthly averages based on 60 years of data from 113 rainfall stations in the Northeast were used to identify the months of December 1977, March and June 1978 as rainy, relatively dry and normal, respectively. The daily behavior of atmospheric water vapor was analyzed for these months. The precipitable water content, the vertically integrated zonal and southern water vapor flows and their divergence were calculated using grid data from the National Meteorological Center, for the hours of 00:00 and 12:00 TMG. The results obtained indicate that the precipitable water content and the transport of water vapor are more favorable to precipitation at night. Flow of water vapor from the Northeast is the condition most conducive to precipitation in the "regime - 3", flow of water vapor from the Northeast-North-Northeast favors the occurrence of rain in the "regime - 5".