Distributed Hydrologic Modeling Using Satellite-Derived Potential Evapotranspiration

Abstract

Satellite-derived potential evapotranspiration (PET) estimates computed from Moderate Resolution Imaging Spectroradiometer (MODIS) observations and the Priestley-Taylor formula (M-PET) are evaluated as input to the Hydrology Laboratory Research Distributed Hydrologic Model (HL-RDHM). The HL-RDHM is run at a 4-km spatial and 6-h temporal resolution for 13 watersheds in the upper Mississippi and Red River basins for 2003-10. Simulated discharge using inputs of daily M-PET is evaluated for all watersheds, and simulated evapotranspiration (ET) is evaluated at two watersheds using nearby latent heat flux observations. M-PETderived model simulations are compared to output using the long-term average PET values (default-PET) provided as part of theHL-RDHMapplication. In addition, uncalibrated and calibrated simulations are evaluated for both PET data sources. Calibrating select model parameters is found to substantially improve simulated discharge for both datasets. Overall average percent bias (PBias) and Nash-Sutcliffe efficiency (NSE) values for simulated discharge are better from the default-PET than the M-PET for the calibrated models during the verification period, indicating that the time-varying M-PET input did not improve the discharge simulation in theHL-RDHM. M-PET tends to produce higher NSE values than the default-PET for the Wisconsin and Minnesota basins, but lower NSE values for the Iowa basins. M-PET-simulated ET matches the range and variability of observed ET better than the default-PET at two sites studied and may provide potential model improvements in that regard. Rights © Copyright 2015 American Meteorological Society (AMS). Permission to use figures, tables, and brief excerpts from this work in scientific and educational works is hereby granted provided that the source is acknowledged. Any use of material in this work that is determined to be "fair use" under Section 107 of the U.S. Copyright Act September 2010 Page 2 or that satisfies the conditions specified in Section 108 of the U.S. Copyright Act (17 USC §108, as revised by P.L. 94-553) does not require the AMS's permission. Republication, systematic reproduction, posting in electronic form, such as on a web site or in a searchable database, or other uses of this material, except as exempted by the above statement, requires written permission or a license from the AMS. Additional details are provided in the AMS Copyright Policy, available on the AMS Web site located at (http://www.ametsoc.org/) or from the AMS at 617-227-2425 or copyrights@ametsoc.org. Simulated discharge using inputs of daily M-PET is evaluated for all watersheds, and simulated evapotranspiration (ET) is evaluated at two watersheds using nearby latent heat flux observations. M-PET-derived model simulations are compared to output using the long-term average PET values (default-PET) provided as part of the HL-RDHM application. In addition, uncalibrated and calibrated simulations are evaluated for both PET data sources. Calibrating select model parameters is found to...

Comparison of Four Different Energy Balance Models for Estimating Evapotranspiration in the Midwestern United States

“…Water 2015, 8,9 acquired on 4 July, 5 August, 24 October, and 11 December (Landsat 5, Thematic Mapper: TM) and four images acquired on 13 August, 29 August, 30 September, and 16 October (Landsat 7, Enhanced Thematic Mapper Plus: ETM+) during the 2001 crop growing season (Figure 1). The Landsat images were processed using Erdas Imagine software (Hexagon Geospatial Inc., Norcross, GA, USA) based on standard procedure where digital number values are first converted to radiance and then to reflectance [20].…”

“…Water 2015, 8,9 to some extent in the METRIC model due to use of weather data in ETr [36]. Furthermore, instantaneous ET is upscaled using daily reference ET (Equation (4)) in the METRIC model, whereas upscaling is done using daily average net radiation (Equation (7)) in the SEBAL model.…”

“…Water 2015, 8,9 15 used for the full Landsat image of approximately 170 km north-south by 183 km east-west. Daily average net radiation was used for upscaling instantaneous ET to daily ET for the SEBAL and SEBS model, whereas GDAS-based ETo was used in the SSEBop model for the same purpose.…”

“…Modeling evapotranspiration (ET), the combined loss of water from soil through evaporation and from vegetation through transpiration, has many applications in agricultural management [1,2], carbon sequestration [3,4], climate modeling [5], drought monitoring [6], energy security [7], hydrological modeling [8], irrigation scheduling [9], and watershed development [10,11]. Various models and techniques are used for accurately estimating ET at field to global scales.…”

A review on evapotranspiration data assimilation based on hydrological models

“…Xie and Zhang (2010) assimilated flow into the Soil and Water Assessment Tool (SWAT) hydrological model, which did not significantly improve the accuracy of ET. The application of data assimilation based on hydrological models has made some progress (Xu et al, 2014) when the assimilated objects are primarily state variables; data assimilation for non-state variables, such as ET, is still being attempted (Spies et al, 2014). The potential of data assimilation in hydrological models should be further investigated.…”