OCO-3 Meets ECOSTRESS: Insights Into Ecosystem Diurnal Water-Use Efficiency From Co-Located Solar-Induced Fluorescence and Thermal Observations

Authors

• Zoe Amie Pierrat, University of California, Santa Barbara
• Thomas P. Kurosu, NASA Jet Propulsion Laboratory
• Abhishek Chatterjee, NASA Jet Propulsion Laboratory
• Joshua B. Fisher, Chapman UniversityFollow
• Maggie Johnson, NASA Jet Propulsion Laboratory
• Le Kuai, NASA Jet Propulsion Laboratory
• Kanishka Mallick, Université de Toulouse
• Nicholas Parazoo, NASA Jet Propulsion Laboratory
• Benjamin Wiebe, Northern Arizona University
• Kerry Cawse-Nicholson, NASA Jet Propulsion Laboratory

Document Type

Article

Publication Date

9-28-2026

Abstract

Terrestrial ecosystem regulation of carbon and water fluxes is critical for constraining climate–biosphere feedbacks but remains poorly quantified across space and time. Here, we evaluate whether co-located observations from NASA's Orbiting Carbon Observatory-3 (OCO-3) and the ECOsystem Spaceborne Thermal Radiometer Experiment on Space Station (ECOSTRESS) can reproduce ecosystem water use efficiency (WUE) dynamics observed at FLUXNET sites across temporal scales, vegetation types, climates, and drought conditions. We created the ECOCO3 data set, which harmonizes OCO-3 and ECOSTRESS observations in space and time. ECOCO3 captures broad seasonal and diurnal carbon and water flux patterns including midday drought responses. Sampling sensitivity analysis shows that ECOCO3 is primarily limited by available sample size for distinguishing vegetation and climate driven differences in WUE. Our findings highlight both the promise and limitations of remote sensing for resolving sub-daily carbon–water coupling.

Plain Language Summary

Plants regulate both carbon uptake and water loss through their leaves, and the balance between these two processes, known as water-use efficiency, reveals how ecosystems respond to climate change. Yet measuring this balance continuously across diverse landscapes remains a fundamental challenge. Here, we tested whether satellites can capture these dynamics by combining remotely sensed carbon and water data from two International Space Station instruments, NASA's Orbiting Carbon Observatory-3 (OCO-3) and ECOsystem Spaceborne Thermal Radiometer Experiment on Space Station (ECOSTRESS), and comparing them against ground-based measurements from the global FLUXNET network. We find that satellites can successfully capture seasonal and daily patterns and drought responses across ecosystems and climates, and that ∼1,000 samples are necessary for resolving sub-daily timing in WUE.

Comments

This article was originally published in Geophysical Research Letters, volume 53, in 2026. https://doi.org/10.1029/2026GL124105

Recommended Citation

Pierrat, Z. A., Kurosu, T. P., Chatterjee, A., Fisher, J. B., Johnson, M., Kuai, L., et al. (2026). OCO-3 meets ECOSTRESS: Insights into ecosystem diurnal water-use efficiency from co-located solar-induced fluorescence and thermal observations. Geophysical Research Letters, 53, e2026GL124105. https://doi.org/10.1029/2026GL124105

Copyright

The authors

Creative Commons License

This work is licensed under a Creative Commons Attribution 4.0 License.