Monsoon 18 Months Ahead: Where Predictability Hides
In 1884, British meteorologist Henry Blanford built the first model for forecasting the Indian monsoon. Nearly a century and a half later, seasonal forecast skill has barely improved.
The Dance of Two Pendulums: Why the Monsoon Can Be Predicted 18 Months Ahead
Two pendulums hang on the same wall, swinging out of sync, but suddenly they move as one, only with an 18-month delay. One pendulum is the Indian monsoon, the seasonal wind that brings rain to South Asian farmland. The other is the deep water of the tropical oceans, which slowly accumulates heat and remembers it for years.
Seasonal Climate Is Predictable Beyond Chaos
Two pendulums suspended from a single invisible spring swing in a shared air current. One always lags the other by exactly half a period: when the first swings left, the second is already returning from the right. By watching the first, you can tell where the second will be half a period later.