High Resolution Three Dimensional Water Vapor Fields for Estimating Spatially Distributed Evapotranspiration Over A Riparian Corridor From a Scanning Raman Lidar
Abstract
The Los Alamos National Laboratory's scanning Raman lidar was used to measure the three dimensional water vapor field with 1.5 m spatial resolution over a Tamarisk forest. The water vapor measurements along with tower based wind field observations were used to estimate the spatially resolved evpotranspiration with 50 m resolution. The method is based upon Monin-Obukhov similarity theory applied to spatially and temporally averaged data. Data from the lidar is used to sense the location and orientation of the surface and the location of the water vapor measurements with respect to that surface. Maps of the spatial distribution of evaporation have been produced showing the evaporation rates at regular intervals throughout the day. The method was applied to a site in central New Mexico during the summers of 1999 and 2000. The estimates of evaporation rates made during the campaign compare favorably with estimates made using eddy covariance methods with differences of approximately 15 percent. While the method has certain limitations, the ability to map the spatial variability of consumptive water use by remote sensing techniques will help to better understand water resource issues.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2001
- Bibcode:
- 2001AGUFM.H41E0326C
- Keywords:
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- 1818 Evapotranspiration;
- 1894 Instruments and techniques;
- 3360 Remote sensing