Introducing Thirstwaves - New Tool for Crop Water Management

New Metric to Track High Evaporative Demand in Agriculture

The University of Idaho and University of Colorado Boulder have introduced a new agricultural concept known as 'thirstwaves.' This innovative metric helps in understanding and preparing for prolonged periods of extreme evaporative demand, which significantly affects agricultural water use.

Developed by Meetpal Kukal from the University of Idaho and Mike Hobbins from the University of Colorado Boulder, thirstwaves focus on prolonged high evaporative demand periods—critical times when plants experience increased water stress. The research was detailed in their recently published paper in "Earth’s Future."

Thirstwaves are defined by instances when evaporative demand exceeds the 90th percentile for at least three consecutive days, based on the gridMET dataset covering the U.S. from 1981 through 2021. This new perspective shifts the focus from average daily values to extremes, which are crucial for understanding and managing water use in agriculture efficiently.

"We’ve been sort of obsessed about heat and heatwaves," said Kukal, stressing the importance of recognizing other environmental factors such as humidity, wind speed, and solar radiation that also drive evaporative demand.

The study highlights how regions like the Midwest, traditionally not considered extreme from an average evaporative demand standpoint, can emerge as hotspots when examining extremes. This insight is crucial for regions where traditional irrigation practices may not suffice under changing climate conditions.

Kukal is also developing a decision-support dashboard to assist farmers in southern Idaho, integrating these findings to optimize irrigation practices amidst these extreme conditions.

Thirstwaves offer a new layer of precision in water management, allowing for more informed decisions that could safeguard agricultural productivity against the backdrop of increasing climate variability.

"This idea of thirstwaves I think is really going to catch on," expressed Hobbins, recognizing the potential of thirstwaves to transform agricultural water management practices significantly.