On the value of thermal infrared remote sensing for water and land management

Thermal infrared (TIR) and visible/near-infrared (VNIR) surface reflectance imagery from remote sensing can be effectively combined in surface energy balance models to map evapotranspiration (ET) and vegetation stress, with broad applications in agriculture, forestry, and water resource management. Particularly valuable are ET retrievals at medium resolution (100 m or finer), resolving scales at which water and land are actively managed over much of the Earth’s surface. At this scale, TIR and VNIR data in the Landsat archive provide a 40-year and growing global record of coupled land and water use change.  In this presentation we will discuss the unique information content conveyed by the land-surface temperature signal regarding the surface moisture status and vegetation health. We will explore applications for field-scale temperature and ET retrievals in promoting sustainable water use, forest health, and regenerative agricultural practices. Widespread and routine generation of ET data at this scale has been enabled by cloud computing technologies, with the OpenET ensemble modeling platform as an example of collaborative geospatial information development.  Looking forward, integration of Landsat with new sources of medium-resolution TIR imagery (e.g., ECOSTRESS, LSTM, TRISHNA, SBG, Landsat-Next, and Hydrosat), as well as all-sky microwave-based temperature retrievals, will improve our ability to detect rapid changes in water use and availability – a key factor in real-time decision making.