Actual Evapotranspiration (Water Use) Assessment of the Colorado River Basin at the Landsat Resolution Using the Operational Simplified Surface Energy Balance Model

Remote Sensing

Ramesh K. Singh¹  Gabriel B. Senay³  Naga M. Velpuri¹  Stefanie Bohms²  Russell L. Scott⁴ 

[1] ASRC Federal InuTeq, Contractor to the US Geological Survey Earth Resources Observation and Science Center, 47914 252nd Street, Sioux Falls, SD 57198, USA; E-mail:;Stinger Ghaffarian Technologies Inc., Contractor to the US Geological Survey Earth Resources Observation and Science Center, Sioux Falls, SD 57198, USA; E-Mail:;US Geological Survey Earth Resources Observation and Science Center, 47914 252nd Street, Sioux Falls, SD 57198, USA; E-Mails:;Southwest Watershed Research Center, US Department of Agriculture, Tucson, AZ 85719, USA; E-Mail:

关键词: evapotranspiration;    energy balance;    geospatial analysis;    hydrologic cycle;    irrigation;    Landsat;    remote sensing;    water use;   

DOI  :  10.3390/rs6010233

来源: mdpi

【 摘 要 】

Accurately estimating consumptive water use in the Colorado River Basin (CRB) is important for assessing and managing limited water resources in the basin. Increasing water demand from various sectors may threaten long-term sustainability of the water supply in the arid southwestern United States. We have developed a first-ever basin-wide actual evapotranspiration (ET_a) map of the CRB at the Landsat scale for water use assessment at the field level. We used the operational Simplified Surface Energy Balance (SSEBop) model for estimating ET_a using 328 cloud-free Landsat images acquired during 2010. Our results show that cropland had the highest ET_a among all land cover classes except for water. Validation using eddy covariance measured ET_a showed that the SSEBop model nicely captured the variability in annual ET_a with an overall R² of 0.78 and a mean bias error of about 10%. Comparison with water balance-based ET_a showed good agreement (R² = 0.85) at the sub-basin level. Though there was good correlation (R² = 0.79) between Moderate Resolution Imaging Spectroradiometer (MODIS)-based ET_a (1 km spatial resolution) and Landsat-based ET_a (30 m spatial resolution), the spatial distribution of MODIS-based ET_a was not suitable for water use assessment at the field level. In contrast, Landsat-based ET_a has good potential to be used at the field level for water management. With further validation using multiple years and sites, our methodology can be applied for regular production of ET_a maps of larger areas such as the conterminous United States.

【 授权许可】

CC BY   
© 2014 by the authors; licensee MDPI, Basel, Switzerland