A decade of remote sensing and evapotranspiration research at USDA-ARS Conservation and Production Research Laboratory

Authors: Gowda, Prasanna; HOWELL, TERRY - Retired ARS Employee; CHAVEZ, JOSE - Colorado State University; PAUL, GEORGE - Texas Agrilife Research; Moorhead, Jerry; HOLMAN, DANIEL - Texas Agrilife Extension; MAREK, THOMAS - Texas Agrilife Research; PORTER, DANA - Texas Agrilife Extension; Marek, Gary; Colaizzi, Paul; Evett, Steven - Steve; Brauer, David

Submitted to: ASABE Annual International Meeting
Publication Type: Proceedings
Publication Acceptance Date: 6/22/2015
Publication Date: 11/10/2015
Citation: Gowda, P., Howell, T.A., Chavez, J.L., Paul, G., Moorhead, J.E., Holman, D., Marek, T.H., Porter, D.O., Marek, G.W., Colaizzi, P.D., Evett, S.R., Brauer, D.K. 2015. A decade of remote sensing and evapotranspiration research at USDA-ARS Conservation and Production Research Laboratory. ASABE Annual International Meeting. CDROM: Paper#152141015.

Interpretive Summary: Farmers need timely information on crop conditions and projected drought. It is widely recognized that remote sensing can provide spatial and temporally distributed information on crop conditions. Timely distribution of this information to producers and water managers in usable form would greatly assist in managing crop production systems efficiently. In the last decade, the USDA-ARS Conservation and Production Research Laboratory's Soil and Water Management Research Unit have conducted numerous remote sensing and evapotranspiration studies to develop methods and tools to assist producers and water managers on irrigation management in the Ogallala Aquifer Region and beyond. This paper discusses the ongoing studies and highlights numerous contributions that have been made by the Soil and Water Management Research Unit to remote sensing and evapotranspiration literature in the last decade.

Technical Abstract: It is widely recognized that image-based remote sensing can provide spatially and temporally distributed information on soil and crop characteristics including tillage and evapotranspiration (ET) from plot to regional scales. ET is an important component of the water balance and the major consumptive use of irrigation water and precipitation on cropland. Numerous ET models have been developed in the last three decades to make use of visible, near-infrared (NIR), shortwave infrared (SWIR), and most importantly, thermal data acquired by sensors on airborne and satellite platforms. However, there are numerous challenges related to spatial and temporal resolutions of remotely sensed data. These include the need for a comprehensive database for model development, enhancement, and testing; availability of cloud-free images; high quality weather data; accurate estimation and partitioning of evaporation and transpiration; and user-friendly platforms for distributing ET maps for irrigation scheduling and groundwater management purposes in arid and semiarid regions such as the Texas High Plains. In the last decade (2005-2015), researchers at the USDA-ARS Conservation and Production Research Laboratory, home of four large monolithic weighing lysimeters, in collaboration with Texas A&M AgriLife Research and Extension and other research institutions in the U.S., have conducted extensive research on ET remote sensing to address the aforementioned challenges. Research accomplishments include development of a comprehensive database consisting of high spatial and temporal resolution remote sensing datasets; measurements of turbulent fluxes with eddy covariance and Bowen ratio systems, sensible heat flux induced light intensity scintillations, net radiation and soil heat fluxes, crop growth parameters, and ET by mass balance. This has allowed the development, enhancement, and testing of numerous remote sensing ET models; development of a framework to generate daily time series ET maps; and development of ET mapping and reference ET software. In this paper, we discuss these accomplishments and the status of ongoing research projects in detail.