Estimating the value of satellite-derived measurements of evapotranspiration to inform irrigation scheduling in California almond orchards

Authors: LAPIDUS, DANIEL - Rti International, Usa; MILLIKEN, CALEB - Rti International, Usa; Knipper, Kyle; SAA, SEBASTIAN - Almond Board Of California; DEVOL, TOM - Almond Board Of California; Kustas, William - Bill; McElrone, Andrew; GALLAHER, MICHAEL - Rti International, Usa; BAMBACH, NICOLAS - University Of California, Davis; Anderson, Martha

Submitted to: Precision Agriculture
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/30/2024
Publication Date: 5/22/2024
Citation: Lapidus, D., Milliken, C., Knipper, K.R., Saa, S., Devol, T., Kustas, W.P., Mcelrone, A.J., Gallaher, M., Bambach, N., Anderson, M.C. 2024. Estimating the value of satellite-derived measurements of evapotranspiration to inform irrigation scheduling in California almond orchards. Precision Agriculture. 1-18. https://doi.org/10.1007/s10961-024-10093-7.
DOI: https://doi.org/10.1007/s10961-024-10093-7

Interpretive Summary: Researchers are developing an "ET Toolkit," utilizing satellite advancements to enhance irrigation practices in California's drought-stricken Central Valley. This innovative approach, targeting precise water use for crops like almonds, promises significant economic and environmental benefits. The toolkit's projected impact is substantial. It's set to boost farmers' annual earnings by $43.7 million through optimized water usage, with a societal economic gain of $122.5 million expected between 2028 and 2033. More than just monetary benefits, the initiative is poised to save a staggering 219,000 acre-feet of water annually. This crucial step towards sustainable agriculture underscores the toolkit's potential in revolutionizing water conservation, with implications extending far beyond agriculture to broader environmental preservation.

Technical Abstract: Advances in satellite remote sensing have led to the development of improved methods and tools for scheduling irrigation. Researchers have been working closely with industry groups for the last decade on developing an “ET Toolkit” that could be used operationally to improve irrigation scheduling for specialty crops in California’s increasingly drought prone Central Valley. A unique collaboration has developed between academic researchers and the Almond Board of California to develop and refine the ET Toolkit to improve water use efficiency through irrigation scheduling for almond growers. In this study, the monetary value of applying the ET Toolkit to improve water use efficiency through irrigation scheduling for almonds is estimated. Benefits are valued by comparing existing irrigation scheduling methods, which rely on calculating crop ET in grower fields based on nearby weather station measurements, to future adoption of a field scale satellite-based actual ET tool. As the tool is not yet commercially available for almonds, the benefits estimated are prospective. Two valuations are conducted; one that captures private benefits to farmers, and another that captures the social value for other water users, based on the price that buyers are paying in active California water markets. Given assumptions on scaling pathways and drought’s impact on values of water, the average annual value to farmers is estimated to be $43.7M, while economic benefits reach $122.5M over the period 2028-2033. Average annual water savings are estimated to be 219,000 acre-feet or the equivalent to fill around 108,000 Olympic sized swimming pools.