Ocean atmosphere interaction dictates quantum of rain distribution over various parts of the globe. Anomalous warming of central and east Pacific Ocean every 2-7 years results in episodes of El Niño. Out of them, few are followed by La Niña.
Oceans when heated up, retain the warmth for a duration of 6-12 months and the atmosphere keeps responding to these changes in the due course. These interactions generate weather cycles over different parts of the globe. Warming of Pacific Ocean results in trade wind reversal and accordingly, the thunderstorm activity shifts from the West Pacific to East and Central Pacific.