Valoración del producto MOD16A2 para su potencial aplicación en la Región Pampeana Argentina

DEGANO F.; NICLÓS R.; RIVAS R.; PUCHADES J.; CARMONA F.

Valladolid

Congreso; XVIII CONGRESO DE LA ASOCIACIÓN ESPAÑOLA DE TELEDETECCIÓN; 2020

AET

Evapotranspiration (ET) is the hydrological variable of greater relevance in the Argentina Pampas Region (APR) because through this process a large part of the water that enters as precipitation is lost from the system. The knowledge of the ET spatial variability is essential to introduce it in hydrological models and the use of satellite products is a key tool for this aim. In this study, the MOD16A2 product of potential ET (ETp) (version 6; MOD16A2.006) was evaluated comparing it with in situ data of 24 stations distributed in the RPA for the years 2012, 2013 and 2014. An overestimation greater than 50% was shown, proving the existence of a systematic error. Due to this finding, we proceeded to calibrate and subsequently correct the product with a linear adjustment equation, thus decreasing the root-mean square difference, from 2.31 to 0.51 mm day-1 and the mean absolute error from 2.08 to 0.37 mm day-1. After this correction, the MOD16A2.006 product improves significantly and can be used for hydrological purposes at the basin scale. It is recommended to evaluate the product in other regions of the world to determine if there are systematic errors, and eventually correct them following the methodology proposed here.