Improvement of reference crop evapotranspiration estimates using limited data for the Brazilian Cerrado.

ABSTRACT: Evapotranspiration (ET) is a key component of the hydrological cycle. Therefore, adequately estimating it is crucial to improving water resource planning and management. One of the most affordable methods of estimating ET is first to estimate reference crop evapotranspiration (ETo) and lat...

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Detalhes bibliográficos
Autores: ALTHOFF, D., RODRIGUES, L. N.
Formato: artículo
Estado:Versión publicada
Fecha de publicación:2022
País:Brasil
Recursos:Empresa Brasileira de Pesquisa Agropecuária (Embrapa)
Repositorio:Repositório Institucional da EMBRAPA (Repository Open Access to Scientific Information from EMBRAPA - Alice)
Idioma:inglés
OAI Identifier:oai:www.alice.cnptia.embrapa.br:doc/1147758
Acesso em linha:http://www.alice.cnptia.embrapa.br/alice/handle/doc/1147758
http://doi.org/10.1590/1678-992X-2021-0229
Access Level:acceso abierto
Palavra-chave:Evapotranspiração
Temperatura
Orvalho
Vento
Descrição
Resumo:ABSTRACT: Evapotranspiration (ET) is a key component of the hydrological cycle. Therefore, adequately estimating it is crucial to improving water resource planning and management. One of the most affordable methods of estimating ET is first to estimate reference crop evapotranspiration (ETo) and later associate it to crop and soil coefficients. The FAO Kc-ETo approach can be used only when ETo is computed with the FAO Penman-Monteith equation. However, low data availability may restict the equations used to estimate ETo. In this study, we assess and calibrate common methods used to estimate ETo under such conditions of limited data availability. Based on the annual calibration, the Makkink (NSE = 0.85) outperformed the Priestley-Taylor (NSE = 0.73), Hargreaves-Samani (NSE = 0.56), and Penman-Monteith temperature approach (NSE = 0.58). The seasonal calibration of parameters showed no significant improvement to the methods assessed (ΔNSE ≤ 0.01), except for the Priestley-Taylor (ΔNSE = 0.06). The performance of temperature-based equations was particularly limited due to the performance of the equation adopted to estimate global solar radiation. Thus, improving the representation of global solar radiation for limited data availability can also play a key role in improving ETo prediction. Keywords: Penman-Monteith temperature approach, tropical savannah, estimating dew-point temperature, average wind speed