Satellite

A NASA satellite has spotted early signs of El Nino, a periodic climate phenomenon that affects weather patterns across the world.

'Record warming'

"We'll be watching this El Nino like a hawk," said Josh Willis, a project scientist at NASA. "If it's a big one, the globe will see record warming."

Kelvin waves

NASA's Sentinel-6 Michael Freilich satellite tracked Kelvin waves, which are a "potential precursor of El Nino conditions in the ocean."

Impact

El Nino causes trade winds to weaken, causing warm water to travel east across the Pacific Ocean instead of westward.

Observations

Satellite observations reveal the Kelvin waves were moving from west to east along the equator toward the west coast of South America.