Global land surface evapotranspiration estimation from meteorological and satellite data using the support vector machine

Evapotranspiration (ET) is the combination process of the surface evaporation and plant transpiration which occur simultaneously, and it links the terrestrial water cycles, carbon cycles and energy exchange. In this study, based on the observations from 242 global FLUXnet sites, with daily average temperature, relative humidity, wind speed, incident solar radiation, NDVI and observed ET as input data, we used a support vector machine to estimate the land surface daily ET at nine different vegetation type sites. The results show that, for all vegetation type sites, when the predicted ET was validated with the eddy covariance measurements, the support vector machine algorithm underestimates the ET and probably could explain 71%-86% of the land surface ET change.

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