Navegando por Autor "GANDU, Adilson Wagner"

Agora exibindo 1 - 3 de 3

Acesso aberto (Open Access)
Interações entre nuvens, chuvas e a biosfera na Amazônia
(Instituto Nacional de Pesquisas da Amazônia, 2005-06) DIAS, Maria Assunção Faus da Silva; COHEN, Júlia Clarinda Paiva; GANDU, Adilson Wagner
A review of results obtained within the Physical Climate component of LBA with respect to the interaction between the biosphere and cloud and rain formation in the Amazon Basin, in different seasons and different regions within the Basin is presented. The deforestation effect and the effect of biomass burning are discussed and the physical processes highlighted based on the data collected in several LBA intensive field campaigns. The complex interactions and the progress in the understanding their evolution based on the new datasets is presented.
Acesso aberto (Open Access)
Radar-observed spatial and temporal rainfall variability near the Tapajós-Amazon confluence
(Universidade Federal do Pará, 2014-12) COHEN, Júlia Clarinda Paiva; FIZJARRALD, David Roy; D'OLIVEIRA, Flávio Augusto Farias; SARAIVA, Ivan; BARBOSA, Illelson Rafael da Silva; GANDU, Adilson Wagner; KUHN, Paulo Afonso Fischer
Standard Amazonian rainfall climatologies rely on stations preferentially located near river margins. River breeze circulations that tend to suppress afternoon rainfall near the river and enhance it inland are not typically considered when reporting results. Previous studies found surprising nocturnal rainfall maxima near the rivers in some locations. We examine spatial and temporal rainfall variability in the Santarém region of the Tapajós-Amazon confluence, seeking to describe the importance of breeze effects on afternoon precipitation and defining the areal extent of nocturnal rainfall maxima.We used three years of mean S band radar reflectivity from Santarém airport with a Z-R relationship appropriate for tropical convective conditions. These data were complemented by TRMM satellite rainfall estimates. Nocturnal rainfall was enhanced along the Amazon River, consistent with the hypothesis that these are associated with the passage of instability lines, perhaps enhanced by local channeling and by land breeze convergence. In the daytime, two rainfall bands appear in mean results, along the east bank of the Tapajós River and to the south of the Amazon River, respectively.
Acesso aberto (Open Access)
Weather forecasting for Eastern Amazon with OLAM model
(2014-12) SILVA, Renato Ramos da; GANDU, Adilson Wagner; COHEN, Júlia Clarinda Paiva; KUHN, Paulo Afonso Fischer; MOTA, Maria Aurora Santos da
The OLAM model has as its characteristics the advantage to represent simultaneously the global and regional meteorological phenomena using the application of a grid refinement scheme. During the REMAM project the model was applied for a few case studies to evaluate its performance on numerical weather prediction for the eastern Amazon region. Case studies were performed for the twelve months of the year of 2009. The model results for those numerical experiments were compared with the observed data for the region of study. Precipitation data analysis showed that OLAM is able to represent the average mean accumulated precipitation and the seasonal features of the events occurrence, but can't predict the local total amount of precipitation. However, individual evaluation for a few cases had shown that OLAM was able to represent the dynamics and forecast a few days in advance the development of coastal meteorological systems such as the squall lines that are one of the most important precipitating systems of the Amazon.