The MODIS-derived Evapotranspiration (ET) is widely used in hydrology, agriculture, and climate research to monitor water availability, assess drought conditions, and evaluate vegetation health. In our lab, the monthly ET data at a 0.01 degree (about 1 km) resolution over Asia and 0.005 degree (about 500 m) over Thailand is derived by aggregating the original 8-day data (with a spatial resolution of 500 meters), providing a comprehensive view of water flux dynamics across various ecosystems. Its high spatial and temporal coverage makes it especially valuable for regional and global studies, providing insights into the impacts of land use change, climate variability, and water resource management. By offering consistent and reliable ET measurements, MODIS ET supports efforts to address water sustainability challenges and improve our understanding of the Earth’s hydrological cycle. 

Figure 1: The monthly total evapotranspiration (ET), aggregated from MODIS ET products at approximately 1 km resolution, is presented for October 2024. ET, representing the combined processes of soil evaporation and plant transpiration, is visualized using a color gradient, with reddish tones indicating higher ET values. This data provides valuable insights for analyzing water cycle dynamics, assessing vegetation health, and managing water resources.

Figure 2: The monthly total evapotranspiration (ET) derived from MODIS ET products at approximately 500 m resolution over Thailand. ET, which represents the combined processes of soil evaporation and plant transpiration, is visualized using a color gradient. Reddish tones indicate higher ET values. These maps highlight the temporal variation in ET over the three months, providing valuable insights into water cycle dynamics, vegetation health, and water resource management.

The MODIS-derived Evapotranspiration (ET) product provides global estimates of evapotranspiration, which is the combined process of water evaporation from the Earth’s surface and transpiration from vegetation. Derived from the Moderate Resolution Imaging Spectroradiometer (MODIS) aboard NASA’s Terra and Aqua satellites, this dataset is based on the Penman-Monteith equation. It integrates remote sensing observations with meteorological inputs such as temperature, humidity, solar radiation, and vegetation characteristics.

More information of the MODIS product can be found at https://lpdaac.usgs.gov/products/mod16a2v061/

Asia
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Spatial Resolution: 0.01 equal-area grid (~1 km)
Temporal Resolution: 1 month
Time span: 2000 – Present
File format: NetCDF
Latency: 2 – 4 Weeks

Thailand
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Spatial Resolution: 0.005 equal-area grid (~500 m)
Temporal Resolution: 1 month
Time span: 2000 – Present
File format: NetCDF
Latency: 2 – 4 Weeks