Evaluation of Global Daily Reference ET Using Oklahoma’s Environmental Monitoring Network—MESONET

Abstract

The objective of this study is to evaluate the potential utility of the USGS Global Data Assimilation System (GDAS) 1-degree, daily reference Evapotranspiration (ET 0 ) products by comparing them with observed Oklahoma mesonet daily ET 0 over a 2 year period (2005)(2006). The comparison showed a close match between the two independent ET 0 products, with bias within a range of 10% for most of the sites and the overall bias of −2.80%. The temporal patterns are strongly correlated, with a correlation coefficient above 0.9 for all groups. In summary, we conclude that (1) the consistent low bias shows the original GDAS ET 0 products have high potentials to be used in land surface modeling; (2) the high temporal correlations demonstrate the capability of GDAS ET 0 to represent the major atmospheric processes that control the daily variation of surface hydrology; (3) The temporal W. Liu et al. and spatial correspondences in trend between independent datasets (GDAS and MESONET) were good. The finding in Oklahoma, a different hydro-climate region from a similar regional study conducted in California by Senay et al. (J Am Water Res Assoc 44(4): [969][970][971][972][973][974][975][976][977][978][979] 2008), reconfirms the reliability and potential of using GDAS reference ET for regional energy balance and water resources management in many parts of the world.

Water balance‐based actual evapotranspiration reconstruction from ground and satellite observations over the conterminous United States

“…As one of the major components of the global hydrologic cycle, evapotranspiration (ET) is a complicated process and composed of evaporation from land surface and water bodies, and transpiration from vegetation to the atmosphere [ Allen et al ., ]. Evaporation and transpiration processes occur simultaneously and are difficult to separate [ Anderson et al ., ; Liu et al ., ; Mallick et al ., ]. Accurately estimating actual ET is of great importance because it is a crucial variable in water resources management, agriculture, and ecology [ Khan et al ., ], and an important process in the fields of hydrology, meteorology and atmospheric sciences [ Chauhan and Shrivastava , ].…”

Intercomparison and evaluation of ten global ET products at site and basin scales

“…The use of Global Modeling and Assimilation Office (GMAO) meteorological measurements with coarse resolution and misclassification of land cover types was identified as the contributor to the error in MOD16 (Ruhoff et al, 2013). The negative higher MBE from SSEBop can be partially attributed to the bias in the absolute magnitude of reference ET (up to 20 %; Senay et al 2013) as well as extraterrestrial solar radiation (Chen et al, 2016;Liu et al, 2011), while the negative MBE in MOD16 could be due to the underlying algorithm (Michel et al, 2016). The substantially different performance between SSEBop and SynthesisET suggests a weak finding that the PML product could be a good product despite the PML not being directly evaluated against the EC tower.…”

Water, Agriculture and Food: Challenges and Issues

“…Recent approaches to estimate ET o from remotely sensed data include those by de Bruin et al ( 2010) and Cammalleri and Ciraolo (2013) which adopted a radiationtemperature equation to estimate daily ET o using radiation and temperature data from the LANDSAF geostationnary satellite. Another innovative approach refers to using the USGS Global Data Assimilation System (GDAS) daily reference evapotranspiration products (Liu et al 2011). Of particular interest is the use of reanalysis products for computing with the PM-ET o equation at various time and space scales (Srivastava et al 2013;Martins et al 2016;Paredes et al 2017).…”