Estimation of evapotranspiration over northeast Asia using modis products and MM5 FDDA data

Evapotranspiration (ET) is significant and necessary to understand the hydrological cycle and to assess water resource at any region. The Moderate Resolution Imaging Spectroradiometer (MODIS) offers promising techniques to monitor regional or global ET patterns. Under cloudy conditions, however, some pixels contain missing data that hamper the continuous monitoring of ET. In this study, MODIS atmospheric and land products were used ET estimates under clear and partial clear sky condition, and atmospheric data produced by the Four-Dimensional Data Assimilation (FDDA) between MODIS products and the Fifth Generation Meso-scale Meteorological Model (MM5) and MODIS land products were used ET estimates under cloudy sky condition. MODIS ET under clear and cloudy sky conditions showed a good agreement with nine flux tower observations in Northeast Asia. These results indicate that MODIS can be applied to monitor ET with reasonable accuracy.