CCN Variability During LBA-SMOCC-EMfiN! 2002 and Its Role on Precipitation Initiation Over the Amazon Basin
Alexandre
Araújo
Costa, Yale University/Funceme, alexandre.costa@yale.edu
(Presenting)
Antonio
Charles
Silvério, Universidade Estadual do Ceará/Universidade Federal do Ceará, silverio@fisica.ufc.br
Gerson
Almeida
Paiva, Universidade Estadual do Ceará, gerson@uece.br
One of the main goals of the LBA-SMOCC-EMfiN! 2002 was to collect data to investigate the impact of biomass burning on regional climate during the “dry-to-wet” transition season over the Amazon basin, Brazil. During the field campaign, a large amount of material coming from fires was released in the atmosphere, producing high cloud condensation nuclei (CCN) concentrations. A wide range of instruments was used to characterize the aerosols and the cloud microphysics during the experiment. Preliminary results suggest that many factors may lead to significant changes in the onset of precipitation over the Amazon, including the increase of the CCN concentration due to forest fires, the presence of giant and/or ultragiant particles in the atmophere and changes in the environmental humidity associated with the large-scale circulation. In case of a moderately poluted environment, as during the transition to the rainy season, observations suggest that giant and ultragiant CCN can, in fact, collaborate with the increase of precipitation efficiency in convective clouds.
Submetido por Antonio Charles Silvério em 23-MAR-2004