Rising temperature is a challenge for developing countries like India as it impacts economic development. Studies have shown that economic growth of tropical developing countries might slow down by 1.3% per year with as little as one-degree rise in the mean temperature. Adding to this body of evidence, a recent study by researchers from the Indian Institute of Technology Delhi (IIT Delhi) has found that variations in temperature affect crop production and worker efficiency—two crucial pillars of our economy. The study is accepted for publication in the journal Environmental Research Letters.
Knowledge about the evolution of temperature variations and seasonal changes plays a role in designing effective strategies for reducing their impact. In this study, the researchers used data about daily maximum and minimum temperatures from 1951 to 2010. They then estimated the annual fluctuations in the temperatures extremes during the favourable ‘growing season’ for crops and studied the temperature trends during the transition period—the time of moderate weather between intense summer and winter and vice versa.
The study found an increasing trend in both night-time and day-time temperatures all over the country. This increase is prominent in the day-time temperature from October to November. “The drastic and joint increase in the day and night temperatures will be a major threat to crop cultivation in India. Especially, the largest wheat production states of Punjab, Haryana and Uttar Pradesh will be severely affected due to the increase in night-time temperature, particularly in winter,” a press release from IIT Delhi quotes the researchers.
The researchers also found that extreme cold temperatures have declined over the study period. However, hot extremes, where the maximum temperatures hover between 30-32o C, have intensified over central India and the Northeast.
The span of pleasant, comfortable days or transition period has reduced across the country, the study found. “The southern west coast – a region encompassing the Western Ghats and Kerala, termed as God’s own country, with natural landscapes and comfortable climate, shows a drastic reduction of comfortable days in recent decades. Though not this intense, similar changes are also observed in east-coast, central India, northeast and foot-hills of Himalayas”, say the researchers.
The findings reveal that summer is encroaching into the transition period. Comfortable days and nights are increasing in the semi-arid regions (northwest), which is otherwise known for the low and high-temperature extremes.
Quantification of temperature changes across India might help policymakers to design region-wise strategies for mitigating its impact.
“Our study highlights the importance of adopting adaptation options such as dynamic cropping pattern, change in crop variants and types, and flexible human working hours in tropical countries like India, to tackle its highly dynamic weather,” conclude the authors.