Articles | Volume 22, issue 20
https://doi.org/10.5194/bg-22-5741-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/bg-22-5741-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
21 Oct 2025
Research article |
| 21 Oct 2025
| 21 Oct 2025
Using GNSS-based vegetation optical depth, tree sway motion, and eddy covariance to examine evaporation of canopy-intercepted rainfall in a subalpine forest
Department of Geography, University of Colorado, Boulder, CO, USA
NSF National Center for Atmospheric Research, Boulder, CO, USA
Vincent Humphrey
Federal Office of Meteorology and Climatology MeteoSwiss, Zurich Airport, Switzerland
Department of Geography, University of Zürich, Zurich, Switzerland
Ethan D. Gutmann
NSF National Center for Atmospheric Research, Boulder, CO, USA
Mark S. Raleigh
College of Earth, Ocean, and Atmospheric Sciences, Oregon State University, Corvallis, OR, USA
David R. Bowling
School of Biological Sciences, University of Utah, UT, USA
Peter D. Blanken
Department of Geography, University of Colorado, Boulder, CO, USA
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Short summary
We compared two techniques that are affected by the amount of liquid water in a forest canopy. One technique relies on remote sensing (a pair of GPSs) and the other uses tree motion generated by the wind. Though completely different, these two techniques show strikingly similar changes when rain falls on an evergreen forest. We combine these measurements with eddy covariance fluxes of water vapor to provide insight into the evaporation of canopy-intercepted precipitation.
We compared two techniques that are affected by the amount of liquid water in a forest canopy....
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