Evapotranspiration estimates derived using thermal-based satellite remote sensing and data fusion for irrigation management in California vineyards

Authors: Knipper, Kyle; Kustas, William - Bill; Anderson, Martha; Alfieri, Joseph; Prueger, John; HAIN, C. - Goddard Space Flight Center; Gao, Feng; Yang, Yun; McKee, Lynn; NIETO, H. - Agrifood Research And Technology Center Of Aragon; HIPPS, L.E. - Utah State University; AISHA, M. - E & J Gallo Winery; SANCHEZ, L. - E & J Gallo Winery

Submitted to: Irrigation Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/25/2018
Publication Date: 10/10/2018
Citation: Knipper, K.R., Kustas, W.P., Anderson, M.C., Alfieri, J.G., Prueger, J.H., Hain, C., Gao, F.N., Yang, Y., McKee, L.G., Nieto, H., Hipps, L., Aisha, M., Sanchez, L. 2018. Evapotranspiration estimates derived using thermal-based satellite remote sensing and data fusion for irrigation management in California vineyards. Irrigation Science. https://doi.org/10.1007/s00271-018-0591-y.
DOI: https://doi.org/10.1007/s00271-018-0591-y

Interpretive Summary: Water management is a critical aspect of successful grape production in California’s Central Valley, which represents nearly 1 million acres of vineyards valued at approximately 6 billion dollars. With reductions in water availability in much of California due to drought and competing water use interests in much of California, it is important to optimize irrigation management strategies. To allocate water more efficiently requires reliable estimates of evpotranspiration (ET) from field to regional scales. In the current study, we investigate the utility of satellite-derived maps of ET using a data fusion approach that combines ET time series retrievals from multiple satellite platforms to generate estimates at both the high spatial (30 meters) and temporal (daily) resolution required for field-scale irrigation management. Comparisons with ET measurements collected over two vineyard sites over multiple years indicate good model performance, with small but persistent seasonal bias patterns. Spatial analyses illustrate the ability of the satellite-based data fusion package to map spatial heterogeneity in seasonal ET over the region as well as within each vineyard. This will enable the development of strategies for integrating these ET mapping time series into an operational irrigation management framework, providing reliable and actionable information regarding vineyard water use and crop stress at field and regional spatial scales and daily to annual timescales.

Technical Abstract: Irrigation in the Central Valley of California is essential for successful wine grape production. With reductions in water availability in much of California due to drought and competing water use interests in much of California, it is important to optimize irrigation management strategies. In the current study, we investigate the utility of satellite-derived maps of evapotranspiration (ET) and the ratio of actual to reference ET (fRET) based on remotely sensed land surface temperature (LST) imagery for monitoring crop water use and stress in vineyards. The multi-scale Disaggregated Atmosphere Land EXchange Inverse (ALEXI/DisALEXI) surface energy balance model, a remote sensing-based ET modeling approach with operational capabilities, is evaluated over two Pinot noir vineyard sites in central California that are being monitored as part of the Grape Remote sensing Atmospheric Profile and Evapotranspiration eXperiment (GRAPEX). A data fusion approach is employed to combine ET timeseries retrievals from multiple satellite platforms to generate estimates at both the high spatial (30m) and temporal (daily) resolution required for field-scale irrigation management. Comparisons with micrometeorological data collected in each vineyard for years 2013 to 2016 indicate reasonable model performance, with small but persistent seasonal bias patterns. Spatial analyses illustrate the ability of ALEXI/DisALEXI/data fusion package to map spatial heterogeneity in seasonal ET and fRET over the region as well as within each vineyard.This will enable the development of strategies for integrating ET mapping time series into operational irrigation management framework, providing actionable information regarding vineyard water use and crop stress at the field and regional scale and daily to annual timescales.