Drought, floods and record heat: What El Nino could bring next

El Nino is gathering strength across the tropical Pacific, raising fears of an extraordinary period of extreme weather that could bring drought to some parts of the world, torrential rain to others and push global temperatures to new highs.

Scientists say the 2026 event could become one of the strongest — potentially the strongest — in modern records. But the significance goes well beyond warmer waters in a remote stretch of the Pacific.

The effects are already beginning to emerge. Drought linked to El Nino is forcing the Panama Canal to reduce the number of ships it can handle, while Sri Lanka is preparing for a potentially damaging sequence of heavy rainfall followed by severe drought.

And there could be another consequence: 2027 could become the hottest year ever recorded, as the temporary warming associated with El Nino combines with the much longer-term rise in temperatures caused by human-induced climate change.

So what exactly is happening, and why does warming in the Pacific have consequences thousands of kilometres away?

What is El Nino?

El Nino is the warm phase of a naturally occurring climate cycle known as the El Nino-Southern Oscillation, or ENSO.

Under normal conditions, trade winds blowing from east to west across the tropical Pacific push warm surface water towards Asia. During an El Nino, those winds weaken, allowing some of that warmer water to move back towards the central and eastern Pacific.

If unusually warm sea-surface temperatures persist for several months, they alter the location of storms and clouds over the Pacific. That, in turn, can change atmospheric circulation much farther away.

The result is not the same everywhere. El Nino can bring hotter and drier weather to some regions while increasing rainfall and flooding risks elsewhere.

Emily Becker, a climate scientist at the University of Miami, told AFP that the changes over the Pacific produce “ripple effects through the entire global atmosphere”.

And the stronger the El Nino, the greater the potential disruption.

“Stronger events mean that we can expect to see more of these expected El Nino impacts,” Michelle L’Heureux, ENSO team lead at the US National Oceanic and Atmospheric Administration’s Climate Prediction Center, told AFP.

But she stressed that individual impacts are not guaranteed.

Why is the 2026 El Nino unusual?

The numbers emerging from the Pacific are attracting particular attention.

Daily sea-surface temperatures in the Nino 3.4 region — a closely monitored area of the equatorial Pacific used to track El Nino — have been running about 2.6C above a rolling 30-year average, according to the Climate Brink dashboard cited by AFP.

Forecasts aggregated by the dashboard suggest the anomaly could peak at around 3.9C in November, considerably higher than the roughly 3C anomaly detected during the powerful 2015 event.

That does not mean global temperatures will suddenly rise by 3.9C. The figure applies to a specific region of the Pacific.

There is also no single universally accepted measure for ranking El Nino events. NOAA now uses the Relative Oceanic Nino Index, or RONI, which compares warming in the Nino 3.4 region with warming across the tropical belt.

Using that measure, NOAA estimates a 69 per cent chance that the current event will become the strongest in its dataset stretching back to 1950, according to AFP.

Could 2027 become the hottest year ever?

This is one of the biggest concerns.

El Nino temporarily releases additional heat into the atmosphere. When that occurs on top of decades of greenhouse gas-driven warming, global temperatures can climb sharply.

Climate scientists Zeke Hausfather and Andrew Dessler calculate that the current El Nino could temporarily add about 0.3C to the underlying global warming trend.

That could put the average global temperature in 2027 at about 1.76C above pre-industrial levels — effectively giving the world, for one year, a taste of temperatures that might otherwise not have been expected until around 2037.

“It’s kind of a preview of the future,” Dessler, a professor at Texas A&M University, told AFP.

Mike McPhaden, a senior scientist at NOAA’s Pacific Marine Environmental Laboratory, offered a similar assessment.

“It’s not inconceivable that 2027 may top out at 1.7C above preindustrial levels,” he said, if current model forecasts prove accurate.

A single year above 1.5C or even 1.7C does not by itself mean the Paris Agreement’s long-term temperature threshold has permanently been breached. But it would demonstrate how extreme individual years can become as the planet continues to warm.

Why the Panama Canal is already feeling the impact

One indication of the wider economic consequences can be found at the Panama Canal.

The waterway, which links the Atlantic and Pacific oceans, depends on freshwater stored in artificial lakes to operate its locks.

With Central America suffering a severe drought associated with El Nino, the Panama Canal Authority says lower-than-expected rainfall in its watershed means fewer ships can be accommodated.

The canal currently allows 36 vessels to pass through each day. That number is due to fall to 34 in early September and then to 32 from September 15.

The consequences could extend far beyond Panama. The canal handles about five per cent of global maritime trade and roughly 40 per cent of US container traffic.

Authorities have also introduced water-saving measures, including restrictions affecting how deeply the largest ships can sit in the water.

The disruption illustrates how a climate phenomenon can quickly become a trade and supply-chain problem.

Sri Lanka braces for drought — and deluge

Thousands of kilometres away, Sri Lanka faces almost the opposite problem: too little rain followed by potentially too much.

Environment Minister Dhammika Patabendi has warned that the country could face what he described as its “worst” El Nino.

Current dry conditions are expected to give way to heavy rainfall from late September through December. That could increase the risk of mudslides in mountainous areas.

But the rains may then disappear.

A prolonged and severe drought is forecast between January and April, threatening water supplies and agriculture in a country where farming employs around a quarter of the workforce.

“The drought will be very severe between January and April, and that is when we will face serious challenges,” Patabendi said.

“We are preparing to mitigate the impending crisis.”

Farmers have already been advised to begin the main rice planting season about two weeks earlier than usual to take advantage of expected rainfall.

What does climate change have to do with it?

El Nino is natural. It occurred long before modern human-induced climate change and typically emerges every two to seven years.

But it is now operating in a much warmer world.

A warmer atmosphere can hold more moisture, potentially making El Nino-associated downpours more intense. Higher temperatures can also dry soils more rapidly, worsening drought in places where rainfall declines.

Scientists are more cautious about another question: whether climate change is making El Nino itself stronger.

Evidence suggesting that it may be doing so is growing, although the issue is not settled.

“Climate change may be amplifying the El Nino cycle itself,” McPhaden told AFP.

Research drawing on coral records, observations dating back to the 19th century and climate modelling suggests El Nino events may have increased in amplitude by about 10 per cent over the past century.

For now, the precise strength of the 2026 El Nino — and exactly where its most severe effects will fall — remains uncertain.

But the combination scientists are watching is clear: an exceptionally strong natural warming event unfolding on a planet that is already substantially hotter because of human activity.

The coming months will reveal just how powerful that combination can be.

With inputs from AFP