Data/hora: 04/06/2024 03:24:19

Biblioteca(s): | Embrapa Territorial.
Tipo da produção científica: | Artigo em Periódico Indexado
Circulação/Nível: | B - 2
Data corrente: | 11/11/2013
Data da última atualização: | 01/06/2017
Autoria: | TEIXEIRA, A. H. de C.; SCHERER-WARREN, M.; LOPES, H. L.; HERNANDEZ, F. B. T.; ANDRADE, R. G.; NEALE, C. M. U.
Afiliação: | ANTONIO HERIBERTO DE C TEIXEIRA, CNPM; MORRIS SCHERER-WARREN, ANA; HÉLIO L. LOPES, UNIVERSIDADE DO VALE DO SÃO FRANCISCO; FERNANDO B. T. HERNANDEZ, UNESP; RICARDO GUIMARAES ANDRADE, CNPM; CHRISTOPHER M. U. NEALE, UTAH STATE UNIVERSITY.
Título: | Application of MODIS images for modelling the energy balance components in the semi-arid conditions of Brazil.
Ano de publicação: | 2013
Fonte/Imprenta: | Remote Sensing for Agriculture, Ecosystems and Hydrology, v. 8887, p. 888719-1-888719-11, 2013.
ISBN: | 1996-756X
Idioma: | Inglês
Conteúdo: | In the semi-arid areas of Petrolina municipality, Northeast Brazil, irrigated agriculture has replaced the natural vegetation, thus the quantification of the energy exchanges between the plants and the low atmosphere is important. MODIS satellite images and agro-meteorological data for the years of 2010 and 2011 were used together, for modelling the energy balance components under these conditions. Surface albedo (0), NDVI and surface temperature (T0) were ther emote sensing parameters required to calculate the latent heat flux (E) and the surface resistance to evapotranspiration (rs) on a large scale. The daily net radiation (Rn) was retrieved from 0, air temperature (Ta) and transmissivity (sw), allowing the quantification of the sensible heat flux (H) by residual in the energy balance. With threshold values for rs, it was possible to do a simplified vegetation classification. The incident solar radiation (RS) partitioned as Rn ranged from 0.40 to 0.51, corresponding respectively to periods after the rainy season and the driest conditions of the year, with the observed differences between irrigated crops and natural ecosystem not significant. Considering all periods along the year, the averaged fractions of Rn partitioned as H, were 31 and 78%, for irrigated crops and natural vegetation, respectively, while as E the corresponding ratios were 69 and 22%. Heat advection from the dry areas surrounding irrigated plots was observed with E exceeding Rn by 9% during the coldest periods. The models tested herein can be used for monitoring the energy exchanges in agro-ecosystems under conditions of land use and climate change.
Palavras-Chave: | Latent heat flux; NDVI; Sensible heat flux; Surface albedo.
Thesaurus Nal: | Surface temperature.
Categoria do assunto: | --
Registro original: | Embrapa Territorial (CNPM)
Exemplares: | CNPM - (3647-1) - UPC - AP - PP - 13/050 - AP - 2013.050 - DIS