CAVALCANTI, E. P.; http://lattes.cnpq.br/8091357561663457; CAVALCANTI, Enilson Palmeira.
Resumo:
In this study the spatial distribution and inter-annual variation of
precipitable water, atmospheric water vapour transport and water budget
over northeast Brazil (NEB) are investigated. The study is confined to the
months March, April and May which represent the rainiest period of the
year for the northern and eastern parts of the region. The inter-annual
variations of the atmospheric parameters is analysed by comparing
conditions during 1977 (normal), 1983 (dry) and 1986 (wet) years. The
Regional Atmospheric Modeling System (RAMS), was used for the
simulation of fields of precipitable water and water vapour flux. Soil and
vegetation data is included in the model and the climatic mean sea surface
temperature is used as the boundary over the ocean. To initialize the RAMS,
data from the National Center for Atmospheric Research/National Center
for Environmental Prediction (NCAR/NCEP) reanalysis is used. The results
reveal fluctuations in precipitable water content due to orographic effects
and characteristics of the ocean-continent interface. The vertically integrated
water vapour flux indicates a relation between the meridional component
and rains in northern part of region. In 1986 (wet year) the water vapour
influx was 1.7 mm/day while during 1983 (dry year) the out-flux was 1.8
mm/day. Rainfall rates derived from precipitable water content variation
agreed well with observed rainfall data. Results of the study suggest that
the RAMS model can provide a reliable tool for the study of atmospheric
water vapour content and transport over NEB.
