India faces threat of groundwater depletion Science

Depletion of water availability in India due to groundwater depletion and climate change; It threatens the livelihoods of a third of the country’s 1.4 billion people and has global implications.

A new study by an international team led by the University of Michigan has found that farmers in India have adapted to higher temperatures by draining groundwater used for irrigation. If the trend continues, the rate of groundwater loss will triple by 2080, threatening India’s food and water security.

According to a press release published on the website “Vis.org” yesterday Friday, groundwater depletion in India and depletion of water reserves due to climate change could affect the livelihoods of one-third of the country’s 1.4 billion people.

Largest consumer of ground water

“We found that farmers are actually increasing irrigation use in response to rising temperatures, an adaptation strategy not considered in previous predictions of groundwater depletion in India, and this is worrisome,” said lead study author Maha Jain, assistant professor. The University’s School of Environment and Sustainability. “Because India is the world’s largest consumer of groundwater and an important supplier to regional and global food supplies.”

The study, published in the journal Science Advances, examines historical data on groundwater levels, climate and crop water stress to identify recent changes in withdrawal rates due to rising temperatures. The researchers also used temperature and precipitation projections from 10 climate models to estimate future rates of groundwater loss across India.

Previous studies have focused on the individual impacts of climate change and groundwater depletion on crop production in India. These studies do not take into account farmers’ decision-making, including how farmers adapt to climate change through changes in irrigation decisions.

Increased demand for groundwater

The new study takes into account the fact that warmer temperatures may increase water demand from stressed crops, leading to increased irrigation by farmers.

“Using our model estimates, under a business-as-usual scenario, rising temperatures could double rates of groundwater depletion in the future and expand hotspots of groundwater depletion to include southern and central India,” said Bhattarai, a former postdoctoral researcher. In Jain’s lab, “Without policies and interventions to protect groundwater, rising temperatures could exacerbate India’s groundwater depletion problem and further challenge India’s food and water security in the face of climate change.”

Previous studies have found that climate change could reduce the productivity of India’s staple crops by up to 20% by mid-century. Meanwhile, the country’s groundwater is depleting at an alarming rate, primarily because water is withdrawn for irrigation.

Create a data set

For the newly published study, the researchers compiled a dataset of groundwater depth, high-resolution satellite observations measuring crop water stress, and records of temperature and rainfall from thousands of wells across India.

A research team led by the University of Michigan found that high temperatures with low winter precipitation are not offset by groundwater recharge during months of increased seasonal precipitation, leading to rapid groundwater decline.

Under different climate change scenarios, estimates of groundwater depletion between 2041 and 2080 average three times the currently estimated depletion rates.