Monsoon season rain cycle

For millennia, farmers, especially small-scale ones, have anxiously anticipated the monsoon rains between June and September to irrigate their crops. Knowing the chances of drought and the timing of rainfall, instead of guessing when to plant and harvest, would offer a boon for yields and a bulwark against disaster. Monsoon rains also supply essential hydroelectric power. It’s not an overstatement to say that the economy and welfare of the entire subcontinent hinge on the monsoon.

Yet the monsoon has remained stubbornly hard to predict. The rains are intimately tied to the rise of the monsoon winds. Both rains and winds are connected to water at the surface of the Indian Ocean. It is this crucial, but less understood, link in the monsoon system that oceanographers are exploring.(Illustration by Gualitiero Spiro Jaeger, © Woods Hole Oceanographic Institution)