How El Niño affects agriculture and global food supply

El Niño develops every two to seven years and usually lasts nine to twelve months. During that window it can dry out maize and rice fields on one continent while flooding them on another, which is why a warm patch of the Pacific Ocean ends up shaping harvests, livestock output and food bills far from the coast. For anyone who grows food or trades it, knowing how the pattern behaves is part of planning a season.

This guide explains what El Niño is, how it changes weather across regions, what it does to crops and livestock, why it can move food prices, and the steps farmers and agribusinesses use to limit the damage. Because El Niño sits on top of a warming climate, its effects increasingly overlap with the longer-term pressures described in our overview of how climate change affects agriculture.

What El Niño is and how it forms

El Niño is the warm phase of a natural cycle called the El Niño-Southern Oscillation, or ENSO. It begins when sea surface temperatures in the central and eastern equatorial Pacific climb well above normal, fed by weaker trade winds and a build-up of warm water below the surface. That ocean warmth changes where tropical rainstorms form, and the effect spreads through the atmosphere to weather systems across the tropics and beyond.

The pattern raises global temperatures while it lasts. The 2023-24 El Niño ranked among the five strongest on record and contributed to 2024 becoming the warmest year on record, at about 1.55 °C above the pre-industrial average.

How El Niño differs from La Niña

La Niña is the opposite phase, when the same stretch of the Pacific turns cooler than normal. The two phases tend to push rainfall in opposite directions in many regions, so a place that floods during El Niño may face drought under La Niña. Between the two sits a neutral state. Each event is different, and its effects depend on how strong it is, when in the year it develops, and how it interacts with other ocean patterns such as the Indian Ocean Dipole.

How often it happens and how long it lasts

El Niño usually starts to develop between March and June and reaches peak strength between November and February. Its effect on global temperature is often felt most strongly in the second year after it begins, which is why the warmest year in a cycle frequently follows the El Niño rather than coincides with it. Forecasters classify each event as weak, moderate, strong or very strong. The popular term "super El Niño" is not part of that official scale.

How El Niño changes temperature and rainfall worldwide

El Niño does not reach every region, and even within a region the effects can vary. Still, the World Meteorological Organization tracks patterns that repeat often enough from one event to the next that forecasters watch for them.

Where it tends to bring more rain

Wetter-than-normal conditions are common in parts of southern South America, the southern United States, areas of the Horn of Africa, and central Asia. For farmers in these areas, the extra rain can help in a dry year or cause waterlogging and flooding in a wet one.

Where it tends to bring drought

Drier conditions often settle over Central America, northern South America, the Caribbean, Australia, Indonesia, and parts of southern Asia. These are major growing regions for rice, maize, palm oil, sugar and coffee, so the dry signal matters well beyond the affected fields. El Niño also tends to suppress Atlantic hurricane activity while fuelling more storms in the central and eastern Pacific.

How El Niño affects crops

Weather drives crop performance at every stage, and El Niño changes the weather a crop meets during germination, flowering, grain filling and ripening. Heat above a crop's tolerance reduces photosynthesis and can stop pollination, while a long dry spell weakens root systems and shrinks yields. The same heat-stress mechanism limits wheat, maize and rice, as covered in our look at the threats and opportunities climate change brings to farming.

Some of these changes help. Where El Niño brings steadier rain and milder temperatures, certain crops yield more than usual. The problem for the global food system is timing and location. When several large producers face heat or drought in the same season, the gains in one region rarely cover the losses in another.

How El Niño affects livestock

Animals feel the heat as directly as crops do. Cattle, poultry and pigs each have a temperature range in which they stay comfortable, and once the air passes that range they spend energy on cooling instead of growth or milk. Dairy cows are especially sensitive: when the temperature-humidity index rises above about 68, cows eat less and milk yield falls, as explained in our guide to reducing heat stress in dairy cattle. Heat also raises the cost of keeping animals fed, because the same dry spells that hurt crops push up feed prices and shrink grazing.

Why El Niño can push up food prices

The world leans on a short list of staple food crops for most of its calories, chiefly wheat, rice, maize and soybean. When a single climate pattern causes harvest losses across several continents at once, global supply tightens in a way that a normal regional shortfall does not, because there are fewer healthy harvests elsewhere to fill the gap.

Demand for staples barely changes with price, since people have to eat, so even a small drop in supply can move prices sharply. Higher-value cash crops such as coffee, sugar and palm oil sit in some of the regions most exposed to El Niño drought, which is why their prices often react first. Government responses can amplify the move: during past shortages, large exporters have restricted shipments of rice and wheat to protect domestic supply, which removed grain from world markets and pushed prices higher still. Extreme weather is already one of the main drivers of acute food insecurity tracked by the FAO.

What past El Niño events have taught us

The strong El Niño of 1997-98 was followed by a long La Niña that ran into 2001, a reminder that the disruption rarely ends when the warm phase does. The 2015-16 event coincided with drought across parts of Africa, Southeast Asia and Central America and with sharp swings in commodity prices. The 2023-24 event helped drive record global heat into 2024. Three points hold across these cases: the strongest temperature effects often arrive in the second year, the regional winners and losers are broadly predictable, and the size of an event does not guarantee the size of its impact in any single place.

How farmers and agribusinesses can prepare

El Niño is one of the few large climate signals that forecasters can flag months ahead, which turns it into a planning tool rather than only a threat. The WMO issues an El Niño/La Niña Update roughly every three months, and national meteorological services translate it into regional outlooks.

A few measures consistently reduce exposure:

Follow the seasonal forecast: Check the latest WMO update and your national service before setting planting dates, and adjust the calendar if a wet or dry signal is strong for your region.
Plant for the expected conditions: In drought-prone seasons, drought-tolerant and short-cycle varieties lower the risk of total loss. Our overview of climate-resilient crops and breeding covers the traits worth looking for.
Manage water early: Efficient systems such as drip irrigation stretch limited water further, and the water-wise techniques used across arid Africa show what is possible on small budgets. Where flooding is the risk, drainage and field grading matter more.
Spread the risk: Growing more than one crop, including hardy orphan crops suited to local conditions, reduces the chance that a single weather pattern wipes out a season.
Protect livestock: Shade, ventilation, clean water and adjusted feeding ease heat stress and hold production through the hottest months.

For agribusinesses, the same forecast lead time supports earlier purchasing, wider sourcing across regions, and supply contracts that account for a volatile season.

Frequently asked questions

Is a "super" El Niño a real category?

No. The WMO classifies events as weak, moderate, strong or very strong, and does not use the term "super El Niño," even though it appears often in the media.

Does climate change cause El Niño?

There is no clear evidence that climate change makes El Niño more frequent or more intense. A warmer ocean and atmosphere can make its effects more severe, because there is more heat and moisture available for heatwaves and heavy rain.

How can I find a forecast for my region?

Start with the WMO El Niño/La Niña Update for the global picture, then check your national meteorological service or regional climate outlook forum, which interpret the global signal for local conditions.