Groundwater levels in North India have been plummeting at an alarming rate over the past two decades, raising serious concerns about the region's food security. A recent study led by Dr. Vimal Mishra from the Indian Institute of Technology (IIT) Gandhinagar has uncovered that consistent weakening of summer monsoons and increasing winter temperatures—both consequences of global warming—are major factors behind this troubling trend.
The research, published in Advancing Earth and Space Sciences, reveals that from 2002 to 2021, the region has experienced a groundwater depletion rate of 1.5 centimetres per year. This depletion has resulted in a staggering net loss of 450 cubic kilometres of groundwater. Such a significant reduction in groundwater levels has had a domino effect, leading to increased irrigation water demands while simultaneously reducing the rate at which groundwater is replenished. The implications of this trend are dire for India’s food security.
Advertisement
Groundwater is a crucial resource for agriculture in North India, a region that is integral to the nation’s food production system, supporting over one billion people. The study highlights that if current rates of groundwater depletion continue, the cropping intensity in the region could decline by a drastic 68 percent. This would severely undermine the agricultural output, threatening the food security of the entire country.
The research team focused on examining the impact of summer monsoon drying and winter warming on groundwater storage. Their findings indicate a significant decline in summer monsoon precipitation, which has decreased by approximately 8 percent between 1951 and 2021. Simultaneously, winters in North India have become noticeably warmer over the same period.
Advertisement
The study also underscores the compounding effect of warmer winters on irrigation demands. It was found that a rise in winter temperatures by just 1°C could increase the irrigation water demand by about 9 percent, irrespective of whether the summer monsoon is normal, dry, or wet. This surge in demand exacerbates the already strained groundwater resources, further complicating efforts to sustain agricultural productivity.
The research sheds light on the urgent need for strategies to manage groundwater resources more effectively, particularly in the context of climate change. The findings underscore the necessity for policymakers to address the growing threat to food security posed by groundwater depletion, emphasising the importance of sustainable water management practices in safeguarding the future of agriculture in India.
As North India continues to grapple with the impacts of climate change, the study serves as a stark reminder of the delicate balance between natural resources and food security. Without immediate intervention, the region risks severe agricultural setbacks, with far-reaching consequences for the nation’s ability to feed its population.