A Pacific SST anomaly: El Niño as a warm tongue. Coupled ocean–atmosphere state of the tropical Pacific. Source: Wikimedia Commons / NASA / USGS / NOAA, public domain or CC.Wikimedia Commons / NASA / USGS / NOAA, public domain or CCWhy this matters
El Niño is a Pacific ocean–atmosphere state, not a storm that hits London. Florida’s wet season, Pacific fisheries and an east-Pacific upwelling coast feel the warm-pool shift more clearly than a British playground. Teleconnections exist: they can bias the odds of a UK winter pattern. They do not write December in advance, and they do not promise snow. A tabloid ENSO is the wrong machine. The Walker cell is an east–west tropical loop; when it sloshes, rainfall and upwelling in the equatorial Pacific move with it. US exam language (APES) and UK A-level both need that honesty. Holderness gales and a Thames flood have their own machines. This lab is the Pacific cell and the refusal to overclaim. Same planet, different teleconnection strength. Stay on the physical state: warm pool, rise, sink, return flow.
A second photograph for the projector script — not the lab cover.Wikimedia Commons / NASA / USGSThe mechanism
The Walker cell is an east–west tropical Pacific circulation. Neutral cartoon: air rises over the warm west Pacific, travels east aloft, sinks over the cooler east, and returns west at the surface — trade-wind sense. El Niño: the warm pool slides east; the rise shifts with it; the east Pacific warms; upwelling there weakens in the school story. La Niña: the opposite extra, a stronger Walker-like pattern, cooler east. ENSO is that coupled ocean–atmosphere state, not a personality and not a UK storm. Teleconnections are remote statistical links. They may bias UK winter odds; they do not schedule a White Christmas. Florida and Pacific fisheries are closer to the engine. This is a school cartoon of an equatorial trough, not a GCM, not a forecast, not a Gulf Stream switch. Colour and the sliding warm-pool sphere are the mechanism. Do not put the warm pool over the UK. Do not call El Niño a hurricane. The slider is a phase, from La Niña through neutral to El Niño, not a volume knob for British rain. West Pacific and east Pacific are labelled coasts on the trough. The readout names the phase.
How to drive the model
Leave ENSO at 0. Name rise in the west, sink in the east, return flow. Slide toward El Niño and watch the warm pool travel east; the Walker arrows follow. Slide the other way for La Niña. Hide labels (L) and ask which coast is west Pacific. Read the phase in the readout before you claim a UK winter. Keyboard: L labels, R reset. The ENSO slider lives in the bar, −1 to +1. No UK snow button. Finish in Check.
If the model will not spin
Without the 3D view: a Walker cell — rise west, sink east — in the neutral Pacific. El Niño slides the warm pool east. La Niña is the opposite extra. ENSO is a Pacific ocean–atmosphere state with teleconnections. Those links may bias UK winter odds; they do not write the month, and they do not promise snow. Florida and Pacific fisheries feel it more clearly. School cartoon, not a GCM, not a personality. The slider is a phase, not a volume knob for British rain.
Film
What is Climate Change? Crash Course Geography #14. Crash Course Geography. About 11 min. Crash Course / Complexly on YouTube. Standard YouTube licence. Educational embed, autoplay off. Autoplay off.
Misconceptions
El Niño is a storm that hits London.
It is a Pacific ocean–atmosphere state with teleconnections.
ENSO always means a White Christmas in the UK.
Teleconnections may bias odds. They do not write the month, and they do not promise snow.
El Niño is a personality of the weather.
It is a named phase of a Pacific state. Neutral, El Niño, La Niña — not moods.
Walker cell
Zonal tropical Pacific circulation. Neutral: rise west, sink east.
walker cell in the enso lab — a TERMS crop, not the glossary plate and not the lab cover. A TERMS crop, not the glossary plate and not the lab cover. Source: Wikimedia Commons / NASA / USGS / NOAA, public domain or CC.Wikimedia Commons / NASA / USGS / NOAA, public domain or CCENSO
Coupled ocean–atmosphere state of the tropical Pacific. Neutral, El Niño, La Niña.
ENSO in the enso lab — a TERMS crop, not the glossary plate and not the lab cover. Coupled ocean–atmosphere state of the tropical Pacific. Source: Wikimedia Commons / NASA / USGS / public domain.Wikimedia Commons / NASA / USGS / public domainEl Niño
Warm phase. The warm pool shifts east in the tropical Pacific.
El Niño: a matching photograph or official scientific figure. Warm phase. Source: Wikimedia Commons / NASA / USGS / NPS, public domain or CC.Wikimedia Commons / NASA / USGS / NPS, public domain or CCLa Niña
Cool phase. The opposite extra: cooler east, stronger Walker-like pattern.
La Niña: a matching photograph or official scientific figure. Cool phase. Source: Wikimedia Commons / NASA / USGS / NPS, public domain or CC.Wikimedia Commons / NASA / USGS / NPS, public domain or CCWarm pool
The pile of warm surface water. It slides east in El Niño in this cartoon.
warm pool in the enso lab — a TERMS crop, not the glossary plate and not the lab cover. A TERMS crop, not the glossary plate and not the lab cover. Source: Wikimedia Commons / NASA / USGS / NOAA, public domain or CC.Wikimedia Commons / NASA / USGS / NOAA, public domain or CCTeleconnection
A remote statistical link. May bias odds; does not write a UK month in advance.
teleconnection in the enso lab — a TERMS crop, not the glossary plate and not the lab cover. A TERMS crop, not the glossary plate and not the lab cover. Source: Wikimedia Commons / NASA / USGS / NOAA, public domain or CC.Wikimedia Commons / NASA / USGS / NOAA, public domain or CCUpwelling
East-Pacific rise of cooler water in the neutral and La Niña school story.
upwelling in the enso lab — a TERMS crop, not the glossary plate and not the lab cover. A TERMS crop, not the glossary plate and not the lab cover. Source: Wikimedia Commons / NASA / USGS / NOAA, public domain or CC.Wikimedia Commons / NASA / USGS / NOAA, public domain or CC