Rainfall Alone Will Not Help Groundwater
In the last few decades, the rapid depletion of groundwater in north India has been the norm. About 95% of India’s groundwater was depleted in the north between 2002 and 2022. The two main factors that influence groundwater storage are groundwater use and the fluctuation of summer monsoon rainfall.
Points to Ponder:
- Groundwater depletion: Over the past few decades, groundwater depletion has been happening quickly in north India. In this area, groundwater was depleted by almost 95% between 2002 and 2022 in India.
- Groundwater depletion factors include: Groundwater use for agriculture and variation in summer monsoon rainfall are the two main causes of groundwater storage depletion.
- Impact of climate change: Groundwater sustainability faces increasing obstacles due to climate change. Increased groundwater pumping for agriculture and an increase in the frequency of hydroclimatic extremes like floods and droughts are both effects of global warming.
- Evapotranspiration’s role: As a result of a warmer climate, there is less water available for groundwater recovery, which restricts groundwater recharge.
- Uncertainty of increased rainfall: Increased summer monsoon rainfall in north India is anticipated to increase due to global warming, but it is unclear whether this will be enough to offset rising evapotranspiration rates and irrigation needs.
- Research findings: Research conclusions To evaluate groundwater storage variability in a warming environment, a study by IIT Gandhinagar used observational data, satellite observations, and hydrological model simulations. The study concluded that if groundwater consumption for irrigation remains at current levels, even with increasing rainfall, the recovery of depleted groundwater will not be sufficient.
- Partial recovery: Even when groundwater extraction is still taking place, periods of heavy precipitation can help with partial groundwater recovery. However, over time and at higher heat levels, enhanced evapotranspiration takes control.
- Inadequate recovery: Even in the most rosy scenario, the anticipated groundwater recovery in the near term (2021–2040) would only replace around 50% of the groundwater lost over the previous two decades. It is impossible to fully replenish the already reduced groundwater.
- Using less groundwater: It’s critical to limit the use of groundwater for irrigation to address the issue. The advantages of more precipitation may be outweighed by the expected rise in groundwater demand for irrigation. As a result, cutting back on groundwater use is essential for effective groundwater recovery.
- Effective irrigation and adaptation: It’s critical to concentrate on improving irrigation efficiency and to think about relocating crop-growing and crop-purchasing areas to lessen the effects of climate change. Even with increased rainfall, several years of drought can further decrease groundwater storage, so for long-term sustainability, adaptive strategies are required.