Comparison of precipitation and incident solar radiation products for South America: observed data and reanalysis / Comparação de produtos de precipitação e radiação solar incidente para a América do Sul: dados observados e reanálises

AUTOR(ES)
DATA DE PUBLICAÇÃO

2007

RESUMO

The goal of this study was to compare nine databases of precipitation and four databases of incident solar radiation of the South America, considering the meridional variation, and the variation across the main continental watersheds (Amazonas, Tocantins, São Francisco, Orinoco, Paraná/Prata, in addition to the main Patagônia basins) and across the main vegetation types (tropical evergreen forest, tropical deciduous forest, woodland, savanna and grassland/steppe). For the precipitation assessment, it was used three products derived from the interpolation of the observed data (CRU; Legates and Wilmott; Leemans and Cramer), three databases based on the composition of rain gauges with remote sensing (TRMM, CMAP and GPCP) and three reanalysis databases (NCEP/NCAR, ERA-40 and CPTEC). For the incident solar radiation assessment, in addition to the reanalysis products, the product generated by the algorithm GL1.2 was also included in the comparison. This product estimates the incident solar radiation from the GOES satellite images. The results show that the annual average precipitation fields of the different products present differentiated behavior between themselves. For example, the CPTEC reanalysis does not represent the main regimes of precipitation in the continent, overestimating the precipitation in the interior of northeast Brazil and underestimating the precipitation in the rest of the continent. There is a substantial agreement among annual mean rain gauge interpolation products, particularly between the products CRU and Leemans and Cramer, which tend to better represent the rainfall regime of Northeast Brazil, for example. The combined rain gauge remote sensing products obtained similar patterns, mainly CMAP and GPCP. Both represent the South Atlantic Convergence Zone (SACZ), a band of higher precipitation that spans from northwestern South America to the southeast of Brazil, extending itself over the Atlantic Ocean. The monthly average values of the incident solar radiation products of the NCEP/NCAR, ERA-40 reanalyses and the GOES estimates were similar for all vegetation types and watershed, while the CPTEC reanalysis presented higher values.

ASSUNTO(S)

precipitação reanalysis incident solar radiation reanálise radiação solar incidente meteorologia precipitation

ACESSO AO ARTIGO

Documentos Relacionados