%0 Conference Proceedings
%4 sid.inpe.br/marte2/2017/10.27.12.41.14
%2 sid.inpe.br/marte2/2017/10.27.12.41.15
%@isbn 978-85-17-00088-1
%F 59260
%T Comparison of energy balance values estimated with METRIC model with eddy covariance data for soybean and maize in irrigation and rainfed system
%D 2017
%A Gaso, Deborah Viviana,
%A Walter-Shea, Elizabeth,
%A Kilic, Ayse,
%@electronicmailaddress dgaso@inia.org.uy
%E Gherardi, Douglas Francisco Marcolino,
%E Aragão, Luiz Eduardo Oliveira e Cruz de,
%B Simpósio Brasileiro de Sensoriamento Remoto, 18 (SBSR)
%C Santos
%8 28-31 maio 2017
%I Instituto Nacional de Pesquisas Espaciais (INPE)
%J São José dos Campos
%P 2423-2430
%S Anais
%1 Instituto Nacional de Pesquisas Espaciais (INPE)
%X This study assessed the performance of the METRIC model for estimation of instantaneous actual evapotranspiration and energy balance components in dry and humid years for soybean and maize, under irrigated and rainfed environments in northeastern of Nebraska. Eddy covariance energy and mass fluxes from three AmeriFlux Nebraska were used to compare METRIC estimates during four growing seasons (twenty one scenes). Additionally, energy balance closure for each day was analyzed. The influence of the reference ET on estimates was investigated. Reference ET for grassland (ETo) and an alfalfa (ETr) were used in METRIC to estimate actual ET. Results indicate that energy balance closure for the estimated fluxes was poor. A linear regression between the sum of net radiation and soil flux (Rn + G) to the sum of sensible and latent heat fluxes (H + LE) yielded a slope of 0.75, intercept of 55.6 and R2 = 0.76. METRIC overestimated actual ET, but results differed depending on the reference ET used (RMSE = 1.66 mm d-1 and 0.97 for ETr and ETo respectively). Estimation of sensible heat flux was poor (RMSE = 92 W m-2), while net radiation (Rn) and soil flux (G) were acceptably estimated (RMSE of 63 and 42 W m-2 respectively). Errors in actual ET estimated for METRIC could be attributed to bias in actual ET measure with eddy covariance or reference ET used in METRIC. These results suggest that would be necessary study which reference ET is more appropriate to use within METRIC depending on the climatic zone.
%9 Uso e qualidade da água
%@language en
%3 59260.pdf