You may have heard talk about a Super El Niño. Here we explain:
Super El Niño: an explainer
Mark Hamblin/2020VISION
We explain what Super El Niño is, what the impacts are and how it interacts with climate change.
#what
El Niño and La Niña are global climate patterns
El Niño and La Niña are recurring climate patterns in the tropical eastern Pacific Ocean. These climate patterns temporarily effect global temperatures and impact rainfall and extreme weather around the world.
El Niño refers to the warming of sea surface temperature that happens every few years due to weakening
La Niña is the opposite where we see episodes of cooler than average sea surface temperature due to strengthening trade winds.
#why
What is the current Super El Niño?
We are currently in an El Niño event, which started in June and is predicted to last into early spring 2027. It’s projected to be the strongest El Niño on record and has been nicknamed a “Super” El Niño for that reason.
#climate
El Niño adds to an already stressed system due to human-driven climate change
El Niño leads to a temporary increase in global atmospheric temperatures. This is a natural process – however, rising background temperatures due to human-driven climate change means when El Niño happens, it adds to an already stressed system. This very strong El Niño, combined with climate change, is likely to break records and cause devastating impacts around the world.
Extreme weather impacts we are seeing should not be blamed on it being “an El Niño year”. Greenhouse gas emissions from human activities are the key driver behind rising global temperatures, and the knock-on effects of climate change. We must realise the part we play in the climate and nature crises, and urgently ramp up our action to tackle it.
Surrey Wildlife Trust Ash Ranges after a fire © Adam Boulton
#impacts
What are the impacts of El Niño around the world?
El Niño typically brings the following impacts to different regions. However, no two El Niño’s are the same, and the stronger signal detected with this year’s “Super” El Niño brings a lot of uncertainty about the weather impacts to come.
Central and South America
- Wetter weather in areas to the south, and with it a risk of serious flooding.
- Warmer and drier weather to the north and tropical areas, increasing the risk of drought and wildfires. Central America is experiencing severe drought leading to huge crop losses in parts of Guatemala, Honduras and El Salvador.
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El Niño leads to nutrient poor waters which can impact entire marine ecosystems.
- Strong El Niño events often lead to severe declines in the Peruvian anchovy fishery. With less phytoplankton to eat and stress in warmer waters, fewer anchovies survive and are available to fishers. Fishery closures and suspensions have ceased operations this year, impacting supply chains that depend on it. In previous Super El Niño events, the collapse of the anchovy fishery has led to species higher in the food chain, such as sea lions, dying in large numbers.
South-east Asia and parts of Australia
- Drier weather, raising the risk of drought and wildfires. Severe wildfires are currently burning across Sumatra and Borneo in Indonesia, with thousands of active fires destroying habitat and threatening the survival of wildlife such as orangutans. Fire risks have been intensified by the El Niño and a prolonged dry season.
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Warm waters can trigger coral bleaching across the tropical Pacific, Indian Ocean, south-east Asia and north-east Australia.
In central and eastern Pacific Ocean
- Islands such as Hawaii, Kiribati and Tuvalu, may experience more frequent and intense tropical storms due to warmer sea temperatures. Hurricane Lala caused flash flooding and mudslides in Hawaii in August, causing severe damage despite not making landfall.
Asia
- Tropical storms are less likely to move towards the Philippines and more likely to affect China, Japan and South Korea.
- A possibly weaker summer monsoon in India, increasing the risk of drought. This year, monsoon rainfall has been below average in India, but uneven rainfall patterns and intense spells of rain have caused severe flooding and landslides across areas such as Kerala.
Africa
- Increased risk of drought in countries in the south from December to February.
- Increased flooding in eastern countries. Forecasts indicate an increased likelihood of wetter-than-normal conditions in the Greater Horn of Africa (Ethiopia, Kenya, Somalia) from October to December.
North America
- Milder winter temperatures in north-west Canada and the US.
- Increasing winter storms and flooding in southern US states and California.
- A quieter hurricane season in some parts of North America and the Caribbean. As peak hurricane season begins for the North Atlantic, activity has been very quiet due to El Niño, with just three “named storms”.
Dry, cracked earth at a reedbed © Logan Walker
Food and supply chains
With increased storms, flooding, drought and wildfire, we’re likely to see the knock-on effects on food supply due to crop failure and altered conditions. Supply chains around the world are likely to be impacted too.
Shipping routes can be impacted by reduced rainfall, which impacts the transportation of food and agricultural products. For example, low water levels have led to reduced shipping traffic through the Panama Canal.
Hydroelectric and nuclear power generation can be reduced, effecting supply and potentially impacting prices.
As a result of El Niño global food inflation is expected to rise, and food security will drop in vulnerable nations too. Developing countries suffer more as those with lower income spend a higher share of their earnings on food. The UN World Food Programme forecasts that nearly 50 million more people in vulnerable communities will be pushed into acute hunger due to the El Niño – where lack of food puts their lives at risk.
Mark Thomas
Marine impacts
El Niño involves warming sea temperatures, and that of course impacts marine life. El Niño reduces the upwelling of cool, nutrient-rich waters and allows warm, nutrient-poor surface waters to accumulate. The lack of nutrients reduces the productivity of phytoplankton – the tiny algae which form the basis of entire marine food webs. With less phytoplankton, entire marine ecosystems are impacted. This means less food for animals such as fish, seabirds and marine mammals. Seals and sea lions have been hit hard in previous El Niño events, with warmer waters changing distributions of prey so they must work harder to find food and leading to significant falls in population.
Coral reefs, which are susceptible to temperature changes, are at risk during El Niño.
Warmer waters can cause wide-spread bleaching – corals expel the microscopic algae which give them their colour and provide the coral with food. Bleaching is a stress-response and leaves the coral very vulnerable.
Some marine species can thrive in El Niño conditions. For example, during the El Niño in 2015, the UK saw jellyfish increase significantly, and ‘blooms’ occurring round our coasts. Jellyfish can cope well with the changeable conditions brought by El Niño and warmer waters benefit their life cycles. As a prey species to animals such as leatherback turtles, jellyfish blooms may have knock-on effects through the food chain.
For populations impacted negatively, these do not recover overnight. As climate change increases the intensity of El Nino events, a key risk is that species, such as sea lions, lack the time for their populations to recover.
#uk
What might the impacts be in the UK?
The European weather system is geographically far away from El Niño so it is hard to predict impacts closer to home. There are some indications we might experience impacts in the UK in the coming autumn and early winter months, with a possible increase in the chance of wetter, stormier weather. Impacts in Europe often lag behind, so we expect to see weather impacts next year too. During El Niño events, heat is released from the oceans, boosting global temperatures temporarily. Impacts of this will continue after the El Niño peaks this winter, and so 2027 is predicted to overtake 2024 as the hottest year on record.
Prolonged dry weather and multiple heatwaves have severely impacted UK harvests this year, and upcoming wet weather will threaten crop planting, livestock rearing and harvests to come.
A quarter of UK food imports come from countries hardest hit by El Niño so we are likely to see supply issues and food prices rise.
This event reminds us of the urgency to act - to rapidly reduce emissions, build resilience, and avoid catastrophic impacts on people and nature.
Restoring and protecting nature can help cope with extreme weather, naturally store carbon and help us turn the tide on the climate and nature crises.
