El Nino Events To Become 'Stronger' And More Intense, Study Finds

FairfaxPeter Hannam

Big El Nino events will increase in intensity and frequency as the planet warms, worsening their related extreme weather impacts, new Australian-led research has found.
The study used 17 climate models to examine how sea surface temperatures by this century's end will change assuming greenhouse gas emission increases remain on their current trajectory.
Extreme El Ninos, such as 1997-98 (left) and 2015-16, are likely to become more common in the future because of climate change. Credit: NASA
The team found a 15 per cent increase in temperature variance in a key region of the Pacific, which translates into 50 per cent more extreme El Ninos, said Dr Wenju Cai, a senior climate scientist at the CSIRO and lead author of the paper published on Thursday in Nature.
"They are stronger and more frequent," Dr Cai said, adding the likelihood of intense El Nino events as measured by sea-surface temperatures will increase from about one every 15 years now to every 10 years on average during this century.
The paper's release comes as delegates from almost 200 nations are meeting in the Polish city of Katowice to hammer out a rulebook for greenhouse gas reductions based on pledges made in the 2015 Paris Agreement.
The results add to a string of recent studies pointing to accelerating impacts of climate change, such as the loss of almost all the thick, multi-year Arctic ice, and the discovery by NASA that glaciers in a large region of eastern Antarctica have "woken up" and are melting.

Stratifying oceans
The Nature researchers described the El Ninos - and their reverse, La Ninas - as "the dominant and most consequential climate variation on Earth".
Conditions are primed in the Pacific for an El Nino, with sea-surface temperatures in the eastern equatorial Pacific at about the threshold level that such events can begin, the Bureau of Meteorology says.
All it needs is for the atmosphere to "couple" with the ocean, creating a process that reinforces the up-welling of warm waters as normally easterly tradewinds stall or reverse.
According to projections, the Pacific Ocean, and most others, become more stratified, meaning more heat and therefore energy stays near the surface rather than gets mixed to lower depths.
"Under climate change, the upper levels of the eastern equatorial Pacific [a centre of El Nino formation] are warming faster than the sub-surface waters," Dr Cai said. "In the future, this coupling of the ocean and atmosphere will be stronger."
Big El Ninos of recent decades include 1982-83, 1997-98 and 2015-16. During these events, western parts of the Americas tend to receive unusually heavy rain, while droughts and wildfires are common in western Pacific regions, including Australia.
Mass coral bleaching is also a feature in the Pacific and beyond, the paper noted.
The paper concludes: "With this projected increase, we should expect extreme weather events associated with the [eastern Pacific El Nino], with important implications for 21st century climate, extreme weather and ecosystems."

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Australia Turns Back On Allies As It Refuses To Cut Emissions Above Paris Pledge

The Guardian

EU and 27 countries vow to toughen commitments as environment minister’s address at COP24 UN climate change summit accused of flying in face of reality
 People at the COP24 UN climate change conference in Katowice, Poland, where Australia has been criticised for its ‘addiction to coal’. Photograph: Omar Marques/SOPA Images/REX/Shutterstock 
Australia will not commit to larger carbon emissions reductions above its Paris agreement target, despite a coalition of former allies and Pacific neighbours urging greater cuts.
In Paris in 2015 Australia was a part of a bloc of countries called the “High Ambition Coalition”, which includes the UK, the EU, New Zealand, the Marshall Islands and Fiji. Australia is outside that bloc now.
On Wednesday, 27 countries and the EU in the High Ambition Coalition called for significantly increased targets for carbon emissions reductions by 2030, in response to a dramatic 1.5C warming report from the Intergovernmental Panel on Climate Change that has dominated negotiations in Poland this week.
“We call on other governments … to join us in striving to step up ambition by 2020 in response to the special report on 1.5C,” it said.
The environment minister, Melissa Price, gave Australia’s formal address to the UN climate talks on Wednesday, saying Australia would “meet and beat” its 2020 Kyoto protocol target and was on track to achieve its Paris goal.
“We are confident that we will meet our 2030 target, which represents a halving of emissions per person,” she said.
“Around the world, countries are laying the foundation for a low-emissions global economy – Australia is no different. We have policies to align strong economic growth with emissions reduction. We are moving towards a new energy future, while ensuring energy remains affordable and reliable.”
But Price’s speech was silent on commitments beyond Australia’s current 26% to 28% Paris pledge for 2030, despite significant pressure from its former coalition partners to lift its target. The Paris agreement was struck with a commitment built in that countries would regularly review and increase their targets.
Her speech did not mention the government’s nascent policy to underwrite power generation with taxpayer money, including of new and existing coal plants.
Also absent was mention of the IPCC’s 1.5C warming report, recognition of which has become the rallying cry for countries urging greater carbon cuts.
The Paris agreement targets, if met, put the world on a 1.5 to 2C warming path, but the 1.5C report warned that the upper end of that range would significantly worsen the risks of drought, floods, extreme heat and poverty for hundreds of millions of people.
The UN climate talks in Katowice, Poland, have hit a significant impasse, with fierce disagreement over the text for a global “rulebook” to implement the 2015 Paris agreement.
Progress has been slow on several key issues, and divisions have emerged between four fossil fuel powers – the US, Russia, Saudi Arabia and Kuwait – and the rest of the world. Australia is seen as closely allied to the US, having appeared at a US-government pro-fossil fuel event this week.
The UN secretary general, António Guterres, flew back to the talks in Katowice on Wednesday, telling delegates: “We are running out of time. To waste this opportunity would compromise our last best chance to stop runaway climate change. It would not only be immoral, it would be suicidal.”
Price, who has kept a low profile during the conference, told delegates the Paris agreement was demonstration of how the international community could work together to address climate change.
“Australia believes that effective international action requires a clear understanding of what countries are committing to, and whether those commitments can be met,” she said. “Paris is premised on parties working together, collectively and transparently …
“Australia calls on all parties to work together to secure a comprehensive, robust, rulebook. Common rules, will lead to action to achieve our shared goals.”
Price said Australia’s natural resources would provide “the low-emissions fuels of the future”.
“Our liquefied natural gas exports could save importing countries around 130m tonnes of carbon dioxide equivalent a year.”
Price did not comment on whether Australia would use carryover carbon credits from the soon-to-be-obsolete Kyoto protocol periods to meet its Paris targets, but it appears almost certain to use the controversial practice.
Using carryover credits – which would allow Australia to claim surplus carbon credits banked during the Kyoto period, largely through land use changes – has been derided as “fake action” by climate analysts, and criticised by countries such as New Zealand.
Australia’s address to the climate talks was criticised by observers and analysts in Katowice.
The Australia Institute’s climate and energy program director, Richie Merzian, said the only things Australia had brought to the UN climate talks were rising emissions and fossil fuel exports.
“To demonstrate Australia’s climate credentials, minister Price’s speech relied almost entirely on policies her government tried to kill off or water down,” Merzian said.
“It was rich of minister Price to rehash [former prime minister Malcolm] Turnbull’s $1bn climate finance pledge, after prime minister Morrison trashed and cut support for UN’s key climate finance body, the Green Climate Fund.”
Simon Bradshaw, Oxfam Australia’s climate change policy adviser, said Australia’s statement would undermine the Pacific’s confidence that it was serious about addressing climate change.
“Australia cannot hide the fact that our emissions are rising and that our addiction to coal is undermining our region’s future,” he said.
“In September, Australia joined other members of the Pacific Islands Forum in reaffirming that climate change is the single biggest threat to the livelihoods, security and wellbeing of the peoples of the Pacific. Yet our actions fly in the face of that reality.”

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