Get used to heat waves: Extreme El Nino events to double

Jan 19, 2014
February 8th 1983, a massive reddish-brown cloud advanced on the city of Melbourne. The dust storm was a consequence of devastating droughts induced by the extreme El Niño of 1982/83. The frequency of such extreme El Niño events occurring in the future as the Earth’s climate warms further is predicted to double. Credit: Australia Bureau of Meteorology/Photographer: Trevor Farrar

Extreme weather events fuelled by unusually strong El Ninos, such as the 1983 heatwave that led to the Ash Wednesday bushfires in Australia, are likely to double in number as our planet warms.

An international team of scientists from organisations including the ARC Centre of Excellence for Climate System Science (CoECSS), the US National Oceanic and Atmospheric Administration and CSIRO, published their findings in the journal Nature Climate Change.

"We currently experience an unusually strong El Niño event every 20 years. Our research shows this will double to one event every 10 years," said co-author, Dr Agus Santoso of CoECSS.

"El Nino events are a multi-dimensional problem, and only now are we starting to understand better how they respond to global warming," said Dr Santoso. Extreme El Niño events develop differently from standard El Ninos, which first appear in the western Pacific. Extreme El Nino's occur when sea surface temperatures exceeding 28°C develop in the normally cold and dry eastern equatorial Pacific Ocean. This different location for the origin of the temperature

increase causes massive changes in global rainfall patterns.

"The question of how global warming will change the frequency of extreme El Niño events has challenged scientists for more than 20 years," said co-author Dr Mike McPhaden of US National Oceanic and Atmospheric Administration.

"This research is the first comprehensive examination of the issue to produce robust and convincing results," said Dr McPhaden.

The impacts of extreme El Niño events extend to every continent across the globe.

The 1997-98 event alone caused $35 US billion in damage and claimed an estimated 23,000 human lives worldwide.

"During an extreme El Niño event countries in the western Pacific, such as Australia and Indonesia, experienced devastating droughts and wild fires, while catastrophic floods occurred in the eastern equatorial region of Ecuador and northern Peru," said lead author, CSIRO's Dr Wenju Cai

In Australia, the drought and dry conditions induced by the 1982-83 extreme El Niño preconditioned the Ash Wednesday Bushfire in southeast Australia, leading to 75 fatalities.

To achieve their results, the team examined 20 climate models that consistently simulate major rainfall reorganization during extreme El Niño events. They found a substantial increase in events from the present-day through the next 100 years as the eastern Pacific Ocean warmed in response to .

"This latest research based on rainfall patterns, suggests that extreme El Niño events are likely to double in frequency as the world warms leading to direct impacts on worldwide."

"For Australia, this could mean summer heat waves, like that recently experienced in the south-east of the country, could get an additional boost if they coincide with extreme El Ninos," said co-author, Professor Matthew England from CoECSS.

Explore further: Cause of El Nino abnormality found

More information: dx.doi.org/10.1038/nclimate2100

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deatopmg
2.3 / 5 (12) Jan 19, 2014
Another dire prediction. OMG! What are we going to do?

What we do is deal with it IF it happens and use the saved funds for proven projects.

I've been reading about doomsday predictions since the mid-'60's. I've read a lot of hype about each one. Got hooked in the early days but, funny thing, I've never seen one come true. It's all been BS for grant money and BS for political control. This is more of the same.
Whydening Gyre
3.3 / 5 (8) Jan 19, 2014
Since Katrina, we've had annual projections as to the numbers of hurricanes to expect in a season, that were... inflated when the respective seasons wound down.
I'm not denying warming or climate change. I just think the panic button is being hit a little too often and hard. It brings to mind the story of the boy who cried wolf...
ubavontuba
2 / 5 (12) Jan 19, 2014
To achieve their results, the team examined 20 climate models that consistently simulate major rainfall reorganization during extreme El Niño events. They found a substantial increase in events from the present-day through the next 100 years as the eastern Pacific Ocean warmed in response to global warming.
Here we go with the "models" again, whereas here is the reality:

http://upload.wik.../Soi.svg

Haven't we supposedly had this global warming thing going on since at least 1950? And still there's no statistically significant change to the pattern?

Oh wait, I get it now. The models are corect ...it's that Ol' Mother Earth is wrong. LOL

Sinister1812
3.6 / 5 (7) Jan 20, 2014
Since Katrina, we've had annual projections as to the numbers of hurricanes to expect in a season, that were... inflated when the respective seasons wound down.
I'm not denying warming or climate change. I just think the panic button is being hit a little too often and hard. It brings to mind the story of the boy who cried wolf...


True, while climate change is a reality, the disaster predictions they keep making (though some could end up being true eventually!) are now being dismissed by a lot of people as "doomsday prophecies", and are causing more people to become denialists. They need to keep things as real as possible imo.
Maggnus
4.7 / 5 (3) Jan 20, 2014
@ Gyre & Sinister - I know what you mean, in that I cringe every time some expert hops on TV and proclaims such and such tornado was the result of global warming. Its as wrong as saying some cherry-picked graph you post over and over means it's not happening.

I think though, that the media is finally starting to smarten up a bit (well except Fox) and are being a little less "alarmist" in their reporting. It is still the case though, that a newspaper headline in big black letters screaming "70 killed by tornado fueled by global warming" is going to sell better than "Typical tornado results in 70 deaths".

Intellegent people look past the headlines. On the whole, though, people are not that smart.