Discover more about El Niño and how it can impact weather patterns around the globe

Weather patterns around the world are complex. One of the major influences on our weather is the ENSO (El Niño Standard Oscillation).

The ENSO is a change in the temperatures and weather in the Pacific Ocean around the equator. It is split into three different phases – a neutral state, La Niña (a cooling state), and El Niño (a warming state). Of the three, it is El Niño that tends to make the headlines for the amount of disruption it can cause. And in summer 2023 we entered an El Niño phase.

So what is El Niño? Is it linked to climate change? And what impacts could it have? Keep reading to learn more.


El Niño is the term used to describe a warming of the water temperatures in the Pacific Ocean.

Typically, in the Pacific Ocean, water temperatures are higher in the west (around Australia and Asia), and cooler in the east (around the west coast of the Americas). The prevalent winds in the ocean also run from east to west. This is the ENSO in its neutral state.

In an El Niño event, the temperatures in the Pacific Ocean rise, particularly around the coast of South America. The prevailing winds across the Pacific also lessen, or in extreme cases can be reversed. This can have a big affect on the world’s weather patterns. It can make some regions of the world more prone to drought and heatwaves, while others are more likely to see severe storms and flooding. Generally during an El Niño event, world temperatures rise. The hottest year on record globally is 2016 – an El Niño year.

The name El Niño means ‘the boy’. It’s believed to come from Peruvian fisherman in the 1600s, who noted warmer ocean temperatures around Christmas. As such they named it ‘El Niño de Navidad’ – the Christ child.

El Niño is a part of a fluctuating pattern of ocean temperatures in the Pacific. Its counterpart is La Niña (the girl). This is when Pacific Ocean temperatures are cooler than average, also impacting world weather. Typically both El Niño and La Niña events appear every two to seven years, with neutral periods in between. However, there is no set pattern and anomalies do occur – for example the winters of 2020 to 2022 were all La Niña events.

Both El Niño and La Niña events tend to last for 9 to 12 months, and their biggest impacts are typically felt in wintertime for the Northern Hemisphere.


El Niño weather events have been known for hundreds of years, and are a natural part of our climate. However, scientists are worried about the potential effects of El Niño when combined with climate change.

It is very likely that as our planet gets hotter, El Niño years could see record global temperatures. Scientists from the World Meteorological Organization are predicting record global temperatures as a result of the combination of global warming and El Niño. This follows several world temperature records already being broken in 2023.

This could also have a knock-on effect on extreme weather events such as droughts, heatwaves, wildfires, storms and floods.

Climate change is also making some of the previously seen impacts of El Niño harder to predict.

For example, previous El Niño years have seen a reduction in the number of storms in the Atlantic off the east coast of the USA and the Caribbean. However, climate change is causing the temperature in the Atlantic to rise, and high temperatures can trigger storms here. As such, it is unknown if future El Niño events will have the same effect.

Scientists do not currently agree whether climate change is likely to affect the frequency of El Niño events. Some have argued that it might. But as global temperatures continue to climb it could make the impacts of El Niño more severe, and harder to predict.

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By disrupting the world’s weather patterns, El Niño has the potential to increase the likelihood of severe weather events in some areas of the world.

In previous El Niño events, severe storms causing damage and flooding have hit the west coast of South America, particularly Peru. This can have impacts further in land also. In 2019, ShelterBox responded to flooding linked to El Niño in Paraguay. Other areas that can see increased storms and rainfall include the south-western USA, central Asia and the Horn of Africa.

Conversely some areas of the world are more likely to see hotter weather and potential drought conditions. At particular risk are Australia, Indonesia, parts of southern Asia such as India, and the central Americas. Previous El Niño events have also brought droughts and heatwaves to some parts of central Africa, such as Ethiopia.

In the wider world, weather patterns could well be affected, and global temperatures rise. This could exacerbate the effects of climate change that are already impacting many people.

While El Niño events are more likely to affect people in certain areas of the globe, it is worth noting that each El Niño is different. As such its impact cannot be predicted with certainty.

For example, El Niño events in the past have brought increased rain to south California. However this did not happen in 2016, when it was hoped potential rains would end the severe drought in the region.

Changes in world weather from El Niño has the potential to cause problems. But it is the decisions that we make as humans that often determines whether a hazard like storms or drought develops into a disaster.

Factors like where homes are built, living conditions, and how well-prepared governments and authorities are to respond to such events can all make a disaster more likely.

At ShelterBox, we avoid using the term ‘natural’ to describe a disaster for this reason. We mustn’t overlook the role that humans have in potentially hazardous weather changes from El Niño becoming a disaster. We also shouldn’t assume that the outcome would be the same, or think there is little we can do to prevent it.

Read more about the language we use to describe disasters and why.



The changes in weather brought about by El Niño has the potential to lead to disasters. Some scientists even think that El Niño events might have contributed to the demise of ancient civilizations in South America, including the Moche and the Inca.

For places impacted by strong storms and heavy rainfall caused by El Niño there is the potential to see severe flooding, or wind damage. ShelterBox previously helped after floods in Peru in 2017 and Paraguay in 2019, both linked to El Niño events. For other locations there may be a reduction in rainfall, leading to heatwaves and drought. These dry conditions could also trigger wildfires.

Devastating though these events have the potential to be, there are other possible impacts from El Niño. Severe storms, excess rainfall, droughts and heatwaves all have the potential to damage and destroy crops and livestock.

There could also be an impact on fish stocks, especially around South America. This could lead to food scarcity, potentially driving displacement and conflict. Some historians believe that an El Niño event led to crop failures that helped spark the French Revolution in 1789.

There could also be a rise in some illnesses due to the changing weather. Warmer and wetter conditions could lead to a rise in mosquito-borne illnesses such as malaria and Dengue fever, water-born illnesses such as cholera, and even the plague.

How can ShelterBox help?

We believe that no one should be without shelter after a disaster.

In the past we responded to flooding related to El Niño in Paraguay. One of those we helped in Paraguay was Lilian. When ShelterBox met her she was living in an emergency shelter with her husband and son after their home flooded in 2019. Her home had been severely damaged by the floods, and she was worried about going back to assess the damage. Like so many, she and her family cannot afford to live away from the river. We gave Lilian a solar light and blankets, which they could use in the emergency shelter. We also gave them a shelter kit, which Lilian planned to use to repair her home.

We cannot know if the current El Niño event will lead to disasters. But with the help of our supporters, we can be there when people affected by disasters need our support most.


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