Login

The preceding decades have witnessed a gradual shift in normal weather events, alarmingly affecting rainfall intensity, pattern, frequency and heat events. Across the world, climate patterns are influenced by various natural phenomena, including El Niño and La Nina. Both originate in the Pacific Ocean, which covers nearly 46 per cent of the earth’s water surface and 32 per cent of its total surface area. It has far-reaching consequences on global weather patterns, including India’s monsoon season. El Niño weakens moisture-laden winds, causes erratic, deficit rainfall across the Indian subcontinent and occurs every two to seven years, lasting for several months. On the contrary, La Niña results in normal to above-normal rainfall in India during the southwest monsoon season and below-normal temperatures during the winter. High pressure (cool air) over the eastern Pacific and low pressure (warm air) over the Indian Ocean push moisture-laden winds toward India. Under normal conditions, the southwest monsoon accounts for about 75 per cent of the country’s annual rainfall.