El Nino is set to become substantially stronger and more frequent, experts warn
Story by Wiliam Hunter
• 10h •
dg>>> Interesting to see Dallas in this list
Cities experiencing the most severe climate whiplash
- Hangzhou, China
- Jakarta, Indonesia
- Dallas, USA,
- Shanghai, China
- Baghdad, Iraq
- Hefei, China
- Canberra, Australia
- Surabaya, Indonesia
- Bangkok, Thailand
- Addis Ababa, Ethiopia
El Niño years are set to become significantly stronger and more regular due to human-induced climate change, a study has found.
The El Niño-Southern Oscillation is a pattern of warm and cool waters that forms in the equatorial Pacific and has a massive role in shaping the global climate.
Currently, the years of intense heat and heavy rain that these events trigger arrive once every two to seven years and are extremely hard to predict.
But scientists now say that El Niño could start to arrive on a regular basis every two to five years by the mid-point of the century.
While a more predictable cycle could help countries prepare for the impacts, the researchers also found that the weather pattern will become much more intense.
According to the researchers, this means much of the world will face back-to-back years of flooding and drought in an effect known as climate whiplash.
During El Niño years, when waters in the Pacific are hot, that could mean heavier winter rains in California, deeper droughts in Australia, and a greater risk of wildfires in Southeast Asia.
Meanwhile, in the cooler La Niña years, the intense fluctuations could create even more powerful hurricanes over the Atlantic.
Although climate change is making most of the world's weather wilder and weirder, this study, published in Nature Communications, suggests that the El Niño-Southern Oscillation may be an exception.
As the world rapidly warms due to the release of greenhouse gases, the conditions that trigger the El Niño-Southern Oscillation are likely to make it more reliable.
This is partly because a warmer Pacific Ocean is more sensitive to feedback between the air and the sea and less capable of dampening the effects of El Niño.
Researchers from South Korea, the USA, Germany, and Ireland used extremely detailed climate simulations of El Niño from 1950 through to 2100.
This revealed that these changes will reach a critical point around 2060, flipping El Niño into an entirely new pattern.
Lead author Dr Malte Stuecker, associate professor at the University of Hawaii Manoa, says: 'In a warmer world, the tropical Pacific can undergo a type of climate tipping point, switching from stable to unstable oscillatory behaviour.
'Enhanced air-sea coupling in a warming climate, combined with more variable weather in the tropics, leads to a transition in amplitude and regularity.'
However, when this happens, the increased intensity and frequency of the El Niño-Southern Oscillation will not be the world's only problem.
Cities experiencing the most severe climate whiplash
- Hangzhou, China
- Jakarta, Indonesia
- Dallas, USA,
- Shanghai, China
- Baghdad, Iraq
- Hefei, China
- Canberra, Australia
- Surabaya, Indonesia
- Bangkok, Thailand
- Addis Ababa, Ethiopia
As this climate cycle stabilises, it will drag other weather systems into synchronising with it.
That includes the North Atlantic Oscillation, which controls weather throughout Europe, and the Tropical North Atlantic Mode, which influences rainfall and hurricane formation in the Caribbean.
This is a big issue because some regions of the world are in the grips of multiple weather patterns.
Currently, when these patterns occur independently, some of their effects can cancel out.
But, in the second half of the century, when multiple weather systems start to coordinate, some regions might be hit by compounding effects.
Likewise, by dragging global weather systems along with it, the Niño-Southern Oscillation will start to have far wider-ranging effects.
This includes parts of Europe which have been, up until now, largely unaffected by El Niño.
Dr Axel Timmermann, of Pusan National University, says: 'This synchronisation will lead to stronger rainfall fluctuations in regions such as Southern California and the Iberian Peninsula, increasing the risk of hydroclimate "whiplash" effects.'
Climate whiplash is a phenomenon in which countries face alternating years of intense drought and heat, followed by heavy rain and flooding.
During droughts, the ground is baked hard and vegetation is killed or burned off in wildfires, which reduces the region's ability to absorb water and increases the flooding risk.
In subsequent years, powerful floods cause damage to waterways and reservoirs, making it even harder to conserve water during the coming drought years.
According to a recent report by Water Aid, the cities currently experiencing the most severe climate whiplash are Hangzhou in China, Jakarta in Indonesia, and Dallas in the USA.
If El Niño years become more common and more intense in the future, these trends are likely to become more severe.
Dr Timmermann says: 'Our findings underscore the need for global preparedness to address intensified climate variability and its cascading effects on ecosystems, agriculture, and water resources.'
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Scientists say that the El Niño and La Niña climate patterns will become more regular and more intense by the mid-point of the century. This simulation shows the temperature of the Pacific during a La Niña event
By 2060, the El Niño-Southern Oscillation will shift from its sporadic pattern to a regular frequency occurring once every two to five years
As the weather system becomes more regular and intense, it will drag other climate systems into sync with it. This includes the Tropical North Atlantic Mode (TNA), which influences rainfall and hurricane formation in the Caribbean
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 Related video: How this winter's weak La Niña could affect your snowfall (The Weather Channel) |
