Termodinâmica da camada limite atmosférica durante a estação chuvosa no oeste da Amazônia - LBA/TRMM 1999

Abstract

In this work are discussed the main aspects of the Atmospheric Boundary Layer (ABL) thermodynamics in the Western Amazonia (Rondonia State), during the wet season 1999. The data had obtained during the LBA/TRMM Wet Season Campaign (Large Scale Biosphere-Atmosphere Experiment in Amazonia / Tropical Rainfall Measurement Mission). The measures was made carried through in two experimental sites. The first one, inside the native Forest (10 5'S; 61° 55'W; 120m) and the other one, in área where the Forest was substituted by pasture (10° 45'S; 62° 21' W; 290m). The results had shown that, during the rainy season, the effect of the deforestation on the thermodynamic characteristics of the ABL is lower when it’s compared with other studies carried during the dry season. The CBL thickness was 749m in the pasture and 747m in the forest. The Convective Boundary Layet (CBL) in the deforested region (pasture) was 0,7K hotter, 07g.kg-1 more humid and the less turbulent. In both the sites the Wind direction was Southeast with force slightly superior in the pasture. During the night, the thickness of nocturnal Boundary Layer (NBL) in pasture was 31% minor, its more stable, hotter 0,2K and 0,5g.kg-1 more dries. Comparing the ABL characteristics observed during the wet season with the one of the dry season we verify that, over the Forest, it does not have significant difference and that the really important contrasts are observed over pasture.