Irrigation (at some level) is essential for much of the US's agricultural production. In the Great Plains region irrigation is used to supply water during dry periods, encourage crop growth, and maximize yields. A new study looks at how irrigation may affect summer heat stress (a combination of temperature and humidity) and public health impacts. The study’s authors include faculty from the Daugherty Water for Food Global Institute at the University of Nebraska.
While irrigation can lower the air temperature it also increases humidity, which could impact heat stress in heavily irrigated areas and nearby regions. However, researchers found that the impact of irrigation strongly depends on the specific heat stress metric used for assessment.
For example, for metrics that heavily account for humidity, irrigation leads to significantly intensified humid heat extremes (up to 9°F increase) and an increased heatwave frequency (up to 3 additional events per year). Conversely, metrics that emphasize temperature more directly suggest that irrigation actually mitigates heat intensity (decreasing temperature metrics by up to 1.8°F).
The inconsistencies in how different heat metrics respond to irrigation underscore the critical need to connect these heat metrics directly with actual public health outcomes to provide a more accurate picture. This connection is vital for developing effective strategies to mitigate heat-related risks in rural communities, especially given the high importance of irrigation for agriculture in the US Great Plains.
