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Goal: Apply Knowledge Globally International Collaborators Develop Easy-to-Use Formulas for Water and Carbon Accounting

Map of the world showing research locations

The network of monitoring sites that provided data for this study. The USCCC allows scientists to share data across the United States and China. Image by Yuan Fang, North Carolina State University.


Ecosystem water use is closely coupled with ecosystem productivity, water availability, and water supplies, but accurate water use accounting remains challenging because of model deficiencies or difficulty of model use in practice. Researchers combined global water use or evapotranspiration measurements with remote sensing products to create a series of simple formulas that can accurately estimate water use and thus water and carbon budgets for seven different land cover types. This work improves understanding of the connections between forest management practices, carbon and water cycles, and changing climate conditions.


Ecosystem water use through evapotranspiration is closely coupled with ecosystem productivity, water availability, and water supply. Although numerous hydrological models exist, accurately estimating water use remains challenging because of model deficiency or difficulty of model use in practice. To improve model accuracy and user experience, researchers (including Eastern Forest Environmental Threat Assessment Center scientists) working together through the U.S.-China Carbon Consortium combined water use or evapotranspiration data from global eddy covariance flux measurements at more than 200 monitoring sites, multiple year remote sensing products, and statistical modeling. Their results produced a new set of formulas that can help models better quantify landscape-level water and carbon balances with readily available meteorological and biophysical information. Scientists world-wide are applying these easy-to-use formulas to map water supply and ecosystem productivity for large basins or regions. In addition, the formulas can help users understand water stress and carbon-water tradeoffs in different ecosystems under climate change and variability and management scenarios.

Principal Investigator
Ge Sun, Research Hydrologist
4854 - Eastern Forest Environmental Threat Assessment Center
Strategic Program Area
Water, Air, and Soil
Environmental controls on seasonal ecosystem evapotranspiration/potential evapotranspiration ratio as determined by the global eddy flux measurements
Monthly land cover-specific evapotranspiration models derived from global eddy flux measurements and remote sensing data
External Partners
U.S.-China Carbon Consortium (USCCC)
North Carolina State University
College of Applied Meteorology, Nanjing University of Information Science and Technology