Climate Change and its Impact on Groundwater Resources in India with Special Reference to Punjab

Climate change is commonly discussed at national and international levels. Changes in global climate are expected to affect the hydrological cycle, altering surface-water levels and groundwater recharge to aquifers with various other associated impacts on natural ecosystems and human activities. The effect of climate change is significantly more on the semiarid, arid and coastal aquifers of the world. In India, the vulnerability is extremely high because of overexploitation of the groundwater and accompanied land subsidence in urbanized areas. The water tables in Punjab have been in continuous decline on a widespread basis, with aquifer depletion rates currently in the range 0.7–1.2 meters per year (approximately equivalent to a net 100–200 millimeters per year of excessive extraction. The cost of extracting groundwater depends on the depth of water table. The fixed cost of extracting groundwater at around 8 meters shows sharp increase. At 8 meters, surface pumps become infeasible to extract water and farmers have to invest in more expensive technologies such as submersible pumps to extract groundwater. Punjab had the largest area experiencing such decline. What is alarming is that the decline has accelerated over time. Measures such as behavioural and structural adaptations, promoting groundwater governance, defining groundwater risk zones and climate change mapping, promoting afforestation, Co₂ sequestration can be adapted for the sustainable utilization of the groundwater reserves.