Using observational data of precipitation and air temperature from1967 to 2008,
which drafted the climatology of these variables and analyzed the weather influenced
by ENOS, were made an identification, characterization and analysis of spatial
thermal effects in Belem (PA), from surface meteorological data and MODIS sensor
images (which is prepared on a platform of the Aqua satellite). The average annual
precipitation was 2978.6 mm/year, and presented an upward trend over the years,
similar behavior has proved to the air temperature. In General, the results show two
centers of greater intensity of surface temperatures: a center in Belem and another
center in nearby town, Ananindeua. These centers vary spatially and temporally in
intensity. During La Niña events, the center of heat island is located in the
neighborhoods closest to Guajara Bay, while in the El Niño events, these
neighborhoods have milder temperatures than the neighborhoods farther from water
sources. The thermal amplitude of surface temperature between urban and rural
areas varies greatly, with largest variation of 30,8°C and the lowest of 16,8°C. Thus,
the highest surface temperatures were observed in neighborhoods with low NDVI,
which is a consequence of a denser urbanization. Urban areas and most vegetated
surfaces show cause/effect relationships very close, especially during the dry
season, this can be realized by correlation that has value greater than 50%. This
study presents results that assist in better understanding of behavior and spatial and
temporal thermal effects in Belem, because the use of satellite images is important
for the identification and characterization of climatic environmental conditions and
urban heat islands.
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