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Place 03 · The Galápagos · Chapter 5 of 7
The Whole World Feels It
A warm patch of sea off South America can empty Peru’s fishing nets, set Indonesia’s forests burning and soak the US Gulf Coast, all in the same winter.
About 15 minutes · 1 video · 1 live map · 2 quick activities
Start here
The ocean pulls, the sky answers
El Niño is only half the story. Warm water heats the air above it, the air rises and rains somewhere new, the winds shift, and the new winds change the ocean again. This back-and-forth between sea and sky is ENSO, and every two to seven years or so it swings from El Niño to its cold twin La Niña and back, rearranging the weather half a world away.
Watch this
See it move
NOAA Ocean Today — El Niño and La Niña Explained. Under two minutes, both twins, and the weather each one hands out.
While you watch, look for
- What the trade winds do in a La Niña year compared with an El Niño year
- Which places get wetter and which get drier
- Something you did not expect. Hold onto it.
The short version
Three things going on here
The twin
La Niña, the cold sister
La Niña is El Niño in reverse: the trade winds blow harder than usual, even more warm water piles up in the west, and extra-cold water wells up in the east. For the Galápagos, La Niña years are the feast after the famine.
The reach
Weather at a distance
When the Pacific’s rainiest air shifts east, the jet streams bend with it and carry the change around the planet. These long-distance links are teleconnections: an El Niño winter tends to be wet and stormy across the US South, dry in Indonesia and Australia, and quiet for Atlantic hurricanes. In 1972 an El Niño, on top of heavy fishing, crashed Peru’s anchoveta, then the biggest fishery on Earth.
The watch
One number for an ocean
NOAA watches the equatorial Pacific with moored buoys, floats and satellites, and boils it all down to the Oceanic Niño Index: how much warmer or colder than normal the central Pacific has been over three months. Plus 0.5 °C or more means El Niño conditions; minus 0.5 °C or less means La Niña. In June to August 2026 it reached +1.8 °C.
Photos: Francisco Davids, Josh Withers, Arnauld van Wambeke / Pexels
Play with it
Find the Pacific’s rain right now
This live map shows today’s rain and thunderstorms. Drag along the equator from Indonesia to South America and find where the heaviest tropical downpours are piling up.
Live map: Windy.com, using ECMWF forecast data.
Two questions to answer while you are in there
- Along the equator, is the heaviest rain over Indonesia in the west or out over the central and eastern Pacific today?
- In mid-2026 an El Niño was building. If it is still going, where would you expect the rain to have moved, and does the map agree?
Try it yourself
Check yourself
Try it
Spot the El Niño
Click every word that describes what happens in an El Niño year, and leave the La Niña ones alone.
Try it · interactive
ENSO Record Reader
Explore NOAA’s real Oceanic Niño Index from 1950 to today: pick any year to see whether it was El Niño, La Niña or neutral, and what happened around the world.
Open the ENSO Record Reader in its own window (opens in a new tab).
Words you will hear
Four terms, that is all
ENSO
Ocean–air cycle between El Niño and La Niña
La Niña
Cold phase: stronger trade winds, colder eastern Pacific
Teleconnection
A weather link between faraway places
Oceanic Niño Index
NOAA's measure of central Pacific warmth
Check your understanding
Practice the whole chapter
Everything in this chapter, in eight quick questions. Retry as often as you like. Read the feedback on every answer, right or wrong, because that is where the learning is.
Practice
Practice: The Whole World Feels It
Eight questions covering the video, the three cards, the four terms and the interactive above.
If you want more
Go deeper
- Oceanography 101 (MiraCosta) 9.12 — Impacts of ENSO Cycles — LibreTexts · 8 minutes
- Oceanography 101 (MiraCosta) 9.10 — Large Cycles in Ocean Climate Variability — LibreTexts · 8 minutes
- NOAA Climate.gov — El Niño & La Niña (ENSO) — NOAA · maps of typical impacts and the latest forecast · 10 minutes
Photo credits (Pexels): Zelch Csaba, Hendryson Taebenu, Francisco Davids, Josh Withers, Arnauld van Wambeke.