Explain how climate change affects the water cycle. Illustrate with examples.

Climate change, occurs primarily by the greenhouse effect due to rising levels of CO₂ and other greenhouse gases, significantly disrupts the water cycle in several interconnected ways:

(1) Increased Evaporation and Atmospheric Moisture: A warmer atmosphere holds more moisture. Warmer temperatures accelerate the rate of evaporation from oceans, lakes, and rivers. This results in a more water-vapour-laden atmosphere. For example, the warming of the Arabian Sea has been observed to cause greater evaporation, which intensifies the southwest monsoon over India, leading to heavier and unpredictable rainfall in some regions.

(2) Changes in Rainfall Patterns: Climate change causes irregular rainfall. Some regions receive very heavy rainfall and floods, while others experience droughts and water shortages.

(3) Melting of Glaciers and Ice: Higher temperatures lead to the melting of glaciers and polar ice caps, increasing river flow initially. However, in the long term, this may reduce the supply of freshwater. Melting ice also raises sea levels and threatens coastal cities like Mumbai and Chennai.

(4) Reduced Groundwater Recharge: Intense, sudden bursts of rainfall lead to increased surface runoff, leaving less time for water to infiltrate the soil. This reduces groundwater recharge, making it difficult to sustain agriculture during dry months.