Research Progress on Quantitative Inversion of Evapotranspiration based on Remote Sensing Technology

Evapotranspiration (ET) is the link between water circulation and energy exchange in the hydrosphere, atmosphere and biosphere. At the global scale, ET accounts for about 60% of the total land precipitation. With the development of flux observation technology, the global long-term continuous observation data can be acquired and shared, and the remote sensing inversion method of ET based on remote sensing technology has made good progress in recent years. In this paper, the existing research progress of remote sensing inversion method for ET is sorted out, summarized, and concluded from the aspects of domestic and international research progress, technical challenges and solutions, application areas, and future development trends. In the future, it is still necessary to carry out research on remote sensing ET inversion methods with high spatial and temporal resolution, effectively consider important information such as surface temperature and soil moisture that can indicate short-term changes in surface ET, and at the same time, strengthen the combination of process-driven physical models and data-driven models, so that the two types of models can complement each other and give full play to each other, which will jointly promote the research level of remote sensing inversion of ET.