Álvaro Corral

In 1960, a meteorologist at a station in Peru records water temperature, while a farmer in India watches the sky waiting for the monsoon. There is no direct link between these two events, but months later one will echo in the other.

An invisible relay race runs through Earth's tropics: a wave of heavy rain and winds, which meteorologists call the Madden–Julian Oscillation, travels eastward at about five meters per second. Most runners tire quickly, but rare marathoners carry the torch all the way across the Pacific.