4.7 Article

Evaluation of a CONUS-Wide ECOSTRESS DisALEXI Evapotranspiration Product

Publisher

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC
DOI: 10.1109/JSTARS.2021.3111867

Keywords

Atmospheric modeling; Land surface temperature; Land surface; Temperature sensors; Stress; Soil; Heating systems; ECOSTRESS; evapotranspiration (ET); validation

Funding

  1. Jet Propulsion Laboratory, California Institute of Technology
  2. National Aeronautics and Space Administration
  3. ROSES ECOSTRESS ScienceTeam grant
  4. 2021 California Institute of Technology. Government

Ask authors/readers for more resources

The DisALEXI algorithm uses land surface temperature to estimate evapotranspiration and incorporates LST products from ECOSTRESS. This study demonstrates the accuracy of DisALEXI-JPL in the contiguous United States and shows good correlation with the original DisALEXI-USDA implementation.
The atmosphere-land exchange inverse disaggregation (DisALEXI) algorithm is a multi-scale energy balance model that estimates evapotranspiration (ET) using land-surface temperature (LST) as a driving remote sensing input. Using LST products from ECOSTRESS, a thermal radiometer mounted on the International Space Station, DisALEXI ET products have been produced over the contiguous United States (CONUS) at 70 m resolution. The goal of this study is to demonstrate the accuracy of the CONUS-wide ET produced by the Jet Propulsion Laboratory (JPL) and to compare the results with the original DisALEXI ET produced by researchers at the United States Department of Agriculture (USDA). DisALEXI-USDA has been produced ad-hoc using Landsat LST, and is routinely produced over six target sites using ECOSTRESS LST. DisALEXI-JPL was implemented in order to expand the spatial coverage. DisALEXI-JPL was evaluated at 26 CONUS eddy covariance sites, showing good correlation, with R-2 = 0.80 and RMSE = 0.81 mm/day, which is comparable to previous DisALEXI validation studies (RMSE similar to 1 mm/day). The two DisALEXI implementations compared well, with R-2 = 0.92. This article evaluates DisALEXI-JPL and shows that the algorithm is valid over a larger segment of CONUS. We also show the impact of quality flags, as pixels with high view zenith angles or high aerosol optical depth showed greater deviation from field measurements. As a product demonstration, we show a regional map of fine-scale ET, where the fine-scale variation over wider areas can detect small areas of stress much sooner than products with coarse resolution representing average conditions.

Authors

I am an author on this paper
Click your name to claim this paper and add it to your profile.

Reviews

Primary Rating

4.7
Not enough ratings

Secondary Ratings

Novelty
-
Significance
-
Scientific rigor
-
Rate this paper

Recommended

No Data Available
No Data Available