Fresh water resources on our planet are now drastically becoming scarce natural resources. The fresh water resources stress may be more deteriorated by increasing climate change and population growth scenarios in the world including East Asia. To better understanding of fresh water availability linked to the land surface and the atmosphere, accurate estimation of the water and energy fluxes should be conducted. Dr. Choi’s research interests are based on an incessant desire to understand those natural hydrologic phenomena that frequently cause floods and droughts and significant damage to people and property. A main research goal is to improve knowledge of land surface hydrologic processes and modeling by integrating remotely sensed data and ground-based data with an emphasis on the soil-vegetation-atmosphere dynamics over a range of scales. Toward this goal, the role of soil moisture and evapotranspiration directly related to many hydrometeorological variables considering spatial-temporal variability and the quantification of uncertainty within the context of the satellite footprint have been sought.