Over the last two decades, the rate of decline of groundwater across North India has been a source of high concern, directly impacting the food security of people in this region. A recent study led by Dr Vimal Mishra of the Indian Institute of Technology (IIT) Gandhinagar has now pinned weakening summer monsoons and rising winter temperatures—consequences of global warming—to be the main drivers of this worrisome trend in groundwater levels in North India.
Results published Monday in the journal Advancing Earth and Space Sciences said that from 2002 to 2021, North India is witnessing a groundwater depleting rate of 1.5 centimeters per year, which amounts to a net loss of about 450 cubic kilometers of groundwater. Dramatic depletion of the ground water levels has a cascading effect—raising irrigation water demands while reducing the natural replenishment of such vital resources. The implications for India’s food security are dire.
Groundwater is literally the lifeline for agriculture in North India, viewed as a hub of food production in the country that caters to the needs of more than one billion people. The research pointed out that if the present extraction rates of groundwater continue unchanged, the cropping intensity could fall by as much as 68% in this region. Such a steep fall in agricultural production would severely undermine food security across the entire nation.
The team focused on the contributions of declining summer monsoon rainfall and warming winter temperatures to groundwater storage. Indeed, their findings indicated that summer monsoon precipitation dropped by about 8% from 1951 to 2021, which helped contribute to further complications for farmers in the region. Over the same period, winters in North India have become perceptibly warm, adding to the strain on groundwater resources.
The multiplying impact of warmer winters on irrigation demand was also presented. In that, even a slight rise of 1°C in the winter temperature is likely to be linked with a 9% rise in irrigation water demand, whether summer monsoon conditions are normal, dry, or wet. This rapid increase in water demand is quite worrying due to the already diminishing groundwater levels, which will further complicate things in terms of maintaining agricultural productivity.
The findings emphasize that much more efficient groundwater management is required, especially in view of an uncertain climate. In view of this, the present study appeals to policymakers to take serious cognizance of the emergent threat of groundwater depletion to food security and strive for sustainable water management for saving the future of Indian agriculture.
The present study proves to be a rude reminder of the fine interface between natural resources and food security if climate change continues to influence North India. Unless intervened into immediately, huge agricultural setbacks are staring at the region, which will have long-term implications on the ability of the nation to feed its people.
Source: Indian Institute of Technology (IIT) Gandhinagar, Advancing Earth and Space Sciences
Credits: Content adapted from the research led by Dr. Vimal Mishra of IIT Gandhinagar.