El Niño The monsoon is a climate cycle where the temperature of the Atlantic Indian Pacific Ocean changes because of movements of air and ocean currents. During this period, the trade winds in the south reverse strengthen weaken, causing the cold warm water to move from the eastern western region to the eastern western region.

During El Niño, trade winds weaken or may even reverse, allowing the area of warmer water to move into the central and eastern tropical Pacific Ocean. During El Niño, the surface winds across the entire tropical Pacific are weaker than usual. Ocean temperatures in the central and eastern tropical Pacific Ocean are warmer than average, and rainfall is below average over Indonesia and above average over the central or eastern Pacific.