This $396,599 federal Project Grant award under the National Science Foundation (NSF) Biological Sciences program (CFDA 47.074) aims to harness advances in remote sensing of solar-induced chlorophyll fluorescence (SIF) to jointly partition ecosystem evapotranspiration (ET) and net ecosystem exchange (NEE) fluxes. The research team from Indiana University will develop a mechanistic approach to partition ET and NEE into their component fluxes, disentangle the mechanisms controlling temporal and spatial dynamics of component fluxes, and improve the Community Land Model (CLM5) by embedding ecophysiological mechanisms into a deep learning framework. This work will provide valuable datasets on individual component fluxes, transpiration-to-ET ratio, and water use efficiency across diverse biomes and hydroclimatic regimes to enhance the fidelity of terrestrial biosphere models in predicting climate change impacts. The grant will also support student training and educational initiatives.