Memory of irrigation effects on hydroclimate and its modeling challenge

However, current earth-system models, used for weather prediction and climate projection, are still in their infancy stage to consider irrigation effects. This study used long-term data collected from two contrasting (irrigated and rainfed) nearby maize-soybean rotation fields, to study the effects of irrigation memory on local hydroclimate.

For a 12 year average, irrigation decreases summer surface-air temperature by less than 1 degrees C and increases surface humidity by 0.52 g kg(-1). The irrigation cooling effect is more pronounced and longer lasting for maize than for soybean. Irrigation reduces maximum, minimum, and averaged temperature over maize by more than 0.5 degrees C for the first six days after irrigation, but its temperature effect over soybean is mixed and negligible two or three days after irrigation.