Abstract
Conceptualizing the implications of climate change for crop evapotranspiration (ETc) and subsequent net irrigation water requirement (NIWR) is critical to sustaining Pakistan’s agriculture and food security. In this article, future ETc, NIWR, and design water requirements (DWR) were projected for the rice–wheat system of Punjab, Pakistan. Consistently increasing temperatures signify an impending hotter transition in the future thermal regime, accompanied by a substantial increase in monsoon rainfall. Future climate warming accelerated ETc and NIWR, which were compensated by 2–5 and 1–2 additional irrigations during the rice and wheat seasons, respectively. Future rice and wheat required 13–18 and 2–5 irrigations per season, respectively. Effective rainfall increments did not compensate for the warming-driven higher ETc and NIWR because of uneven and erratic rainfall distribution. Rainfall occurrence and the duration of peak irrigation demand were mismatched, resulting in surplus rainwater availability during the future rice season. The results suggest that DWR for 5- and 10-year return period droughts during the baseline period (965 and 1000 mm, respectively) should be revised to accommodate the additional 100–200 mm of irrigation water per season; otherwise, the study area will face an acute water shortage in the future.
Highlights
According to the recently released Sixth Assessment Report (AR6) of the Intergovernmental Panel on Climate Change (IPCC), human-induced anthropogenic interventions have unequivocally changed the Earth’s climate, which is evident from global surface warming, sporadic rainfall patterns, intensification of the water cycle, and an overall energy imbalance in the atmosphere [1]
Irrigation schedules were generated based on future water requirements of the wheat–rice system of Punjab, Pakistan
Future wheat and rice seasons were distinguished by distinctly high warming rates, with the Tmin remaining significantly higher than the Tmax
Summary
According to the recently released Sixth Assessment Report (AR6) of the Intergovernmental Panel on Climate Change (IPCC), human-induced anthropogenic interventions have unequivocally changed the Earth’s climate, which is evident from global surface warming, sporadic rainfall patterns, intensification of the water cycle, and an overall energy imbalance in the atmosphere [1]. Several studies have quantified the severity of the climate change phenomenon in Pakistan and its implications for crop production and water requirements [3,6,7,9,14,15,16]. The irrigation schedules and design water requirements (DWR) are projected to meet the future crop water requirements of the rice–wheat system of Punjab, Pakistan. Irrigation schedules were generated based on future crop water requirements while considering the composite effect of all influential climate variables, and the DWR were projected for 5and 10-year return period droughts. The study outcomes will contribute to developing an efficient irrigation scheduling strategy for tackling the climate change threats to the rice–wheat system in Punjab, Pakistan. We estimated the future DWR, which may be used to develop an integrated water resource policy for better distribution of limited water resources and canal water supply regulation
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
