Efficient irrigation leads to reduction in moist heat stress: IIT Gandhinagar research

Transitioning from traditional irrigation to drip irrigation systems decreases water use and has less of an impact on humidity

Irrigated agriculture areas have expanded greatly throughout the Indo-Gangetic plain, and water use has consequently increased, contributing to an increase in summer wet-bulb temperature. A study in the AGU journal Earth’s Future, by researchers at the Indian Institute of Technology, looks into improved water savings and reduction in moist heat stress caused by efficient irrigation.

The researchers used observations and simulations from the Weather Research Forecasting (WRF) model to examine the impact of efficient (drip) irrigation on moist heat stress and water savings over the Indo-Gangetic Plain. Irrigated area has increased more than 20 per cent over the Indo-Gangetic Plain during the 1970-2005 period.

The study highlights:
From 1970 to 2005, irrigated agricultural areas in the Indo-Gangetic plain grew by 20 per cent.
Greater irrigation use has increased humidity, leading to higher wet-bulb summer temperatures and greater heat stress, and contributing to declines in groundwater.
Heat stress is a primary hazard for agricultural workers.
Transitioning from traditional irrigation to drip irrigation systems decreases water use and has less of an impact on humidity.
The irrigation expansion partly contributed to the rise of 0.46 °C (P-value < 0.05) in the summer (April-May) season wet-bulb temperature over the Indo-Gangetic Plain, which is a measure of moist heat stress.