(The Guardian) IPCC Steps Up Warning On Climate Tipping Points In Leaked Draft Report

The Guardian - Fiona Harvey and agencies

Scientists increasingly concerned about thresholds beyond which recovery may become impossible

Dried area of the Penuelas Lake, in Valparaiso, Chile. Hunger, drought and disease will afflict tens of millions more people within decades, according to a draft UN assessment. Photograph: Martin Bernetti/AFP/Getty Images

Climate scientists are increasingly concerned that global heating will trigger tipping points in Earth’s natural systems, which will lead to widespread and possibly irrevocable disaster, unless action is taken urgently.

The impacts are likely to be much closer than most people realise, a a draft report from the world’s leading climate scientists suggests, and will fundamentally reshape life in the coming decades even if greenhouse gas emissions are brought under some control.

The Intergovernmental Panel on Climate Change is preparing a landmark report to be published in stages this summer and next year. Most of the report will not be published in time for consideration by policymakers at Cop26, the UN climate talks taking place in November in Glasgow.

A draft of the IPCC report apparently from early this year was leaked to Agence France-Presse, which reported on its findings on Thursday. The draft warns of a series of thresholds beyond which recovery from climate breakdown may become impossible.

It warns: “Life on Earth can recover from a drastic climate shift by evolving into new species and creating new ecosystems … humans cannot.”

Tipping points are triggered when temperatures reach a certain level, whereby one impact rapidly leads to a series of cascading events with vast repercussions.

For instance, as rising temperatures lead to the melting of Arctic permafrost, the unfreezing soil releases methane, a powerful greenhouse gas that in turn causes more heating.

Climate tipping points could topple like dominoes, warn scientists.  Read more

Other tipping points include the melting of polar ice sheets, which once under way may be almost impossible to reverse even if carbon emissions are rapidly reduced, and which would raise sea levels catastrophically over many decades, and the possibility of the Amazon rainforest switching suddenly to savannah, which scientists have said could come quickly and with relatively small temperature rises.

Bob Ward, the policy and communications director at the Grantham Research Institute on Climate Change and the Environment at the London School of Economics, said: “Scientists have identified several potential regional and global thresholds or tipping points in the climate beyond which impacts become unstoppable or irreversible, or accelerate.

"They could create huge social and economic responses, such as population displacements and conflict, and so represent the largest potential risks of climate change. Tipping points should be the climate change impacts about which policymakers worry the most, but they are often left out of assessments by scientists and economists because they are difficult to quantify.”

Previous work by the IPCC has been criticised for failing to take account of tipping points. The new report is set to contain the body’s strongest warnings yet on the subject.

Simon Lewis, a professor of global change science at University College London, said: “Nothing in the IPCC report should be a surprise, as all the information comes from the scientific literature.

"But put together, the stark message from the IPCC is that increasingly severe heatwaves, fires, floods and droughts are coming our way with dire impacts for many countries.

"On top of this are some irreversible changes, often called tipping points, such as where high temperatures and droughts mean parts of the Amazon rainforest can’t persist. These tipping points may then link, like toppling dominoes.”

Earth is trapping ‘unprecedented’ amount of heat, Nasa says.  Read more

He added: “The exact timing of tipping points and the links between them is not well understood by scientists, so they have been under-reported in past IPCC assessments.

"The blunter language from the IPCC this time is welcome, as people need to know what is at stake if society does not take action to immediately slash carbon emissions.”

Myles Allen, a professor of geosystem science at the University of Oxford, declined to comment on the draft report but stressed that avoiding dire impacts was still possible. “It’s important people don’t get the message ‘we’re doomed anyway so why bother?’.

"This is a fixable problem. We could stop global warming in a generation if we wanted to, which would mean limiting future warming to not much more than has happened already this century.

"We also know how. It’s just a matter of getting on with it,” he said.

According to AFP, the IPCC draft details at least 12 potential tipping points. “The worst is yet to come, affecting our children’s and grandchildren’s lives much more than our own,” the report says.

The report may be subject to minor changes in the coming months as the IPCC shifts its focus to a key executive summary for policymakers.

It says that with 1.1C of warming above pre-industrial levels clocked so far, the climate is already changing.

A decade ago, scientists believed that limiting global warming to 2C above mid-19th-century levels would be enough to safeguard the future.

That goal is enshrined in the 2015 Paris agreement, adopted by nearly 200 nations who vowed to collectively cap warming at “well below” 2C – and 1.5C if possible.

On current trends the world is heading for 3C at best.

Earlier models predicted that Earth-altering climate change was not likely before 2100.

But the UN draft report says prolonged warming even beyond 1.5C could produce “progressively serious, centuries-long and, in some cases, irreversible consequences.”

Links

• (UK UNILAD) Earth Temperature Could Reach ‘Tipping Point’ Within Five Years, Study Warns
• (AU ABC) Financial Regulator APRA To Stress-Test Banks On Climate Change, To Examine What Would Happen In A 3-Degrees-Hotter World
• Antarctic Glacier Will Reach Tipping Point
• Gulf Stream System Slows To Its Weakest In A Thousand Years, Putting U.S., Europe At Risk
• Melting Glaciers, Rising Seas: Approaching Climate Tipping Points
• Positive Tipping Points Offer Climate Hope
• The Tipping Points At The Heart Of The Climate Crisis
• Guest Post: The Irreversible Emissions Of A Permafrost ‘Tipping Point’
• (Phys.org) Crushing Climate Impacts To Hit Sooner Than Feared: Draft UN Report
• (USA PBS) A Leaked UN Report Warns ‘Worst Is Yet To Come’ On Climate Change. Here’s How You Can Help
• (CA CBC) Some Climate Change Fixes Could Drive Extinctions, UN Warns
• (AU) Australia Accused Of 'Shamefully' Holding Back Global Action On Climate Change
• World ‘Walking Blindfolded Into A Minefield’ Due To Climate Inaction
• (AU Witnessing The Unthinkable
• Climate Worst-Case Scenarios May Not Go Far Enough, Cloud Data Shows
• Why Tackling Global Warming Is A Challenge Without Precedent

(AU ABC) Australia Avoids Great Barrier Reef Global Embarrassment, But The Dangers Of Climate Change Remain For The Reef

ABC News - Michael Slezak

Australia has avoided the embarrassment of the Great Barrier Reef being labelled in danger after lobbying by Environment Minister Sussan Ley. (ABC/AAP)

When the scientific advisors to UNESCO recommended the Great Barrier Reef be added to UNESCO's in-danger list, Environment Minister Sussan Ley claimed the process stunk.

She argued it was a result of dirty politics, not science.

So it's a matter of some irony that her victory this week — avoiding an in-danger list for at least another couple of years — comes after some skilled politicking.

If there are claims that politics have swayed outcomes, then let's strip away the politics and look at the facts — the things that actually matter to the reef.

Great Barrier Reef avoids

'in danger' tag by UNESCO

The Great Barrier Reef will not be added to UNESCO's "in danger" list this year, after environment minister Sussan Ley's whirlwind diplomatic effort won enough support. Read more

In 2015, the Great Barrier Reef narrowly escaped being listed as "in danger".

And regardless of that decision, and whether it fits UNESCO's criteria this time around, the facts show the reef clearly in danger.

'Dead corals don't make babies'

Mass bleaching events on the reef were a new — but still relatively rare — phenomenon back in 2015. The first one was in 1998 and then there was another in 2002.

The combined impact of those two bleaching events, outbreaks of crown of thorns starfish and severe cyclones mean the reef has lost half of its hard coral cover since 1985. 

That rate of loss is unprecedented in the previous 400 years, according to the Australian Institute of Marine Science.

Layered on top of that, the reef was being assaulted by fossil fuel giants developing major infrastructure along its coast.

Three massive LNG plants had just been built in the World Heritage Area on Curtis Island off Gladstone, the construction of which involved dredging.

And Adani was proposing to expand the Abbot point coal terminal, and dump dredge spoil in the World Heritage Area.

Adani's Abbot Point coal storage and dam beside Caley Valley wetlands in north Queensland. (Supplied: Adani)
 

Regardless, Australia was spared the embarrassment of an in-danger listing at the time, with stern words from UNESCO about acting on climate change, and the need for the reef's declines to halt and "reverse".

But fast forward six years and Adani's dumping proceeded, mass bleaching events hit three times in five years, and Australia's policies on climate change have not grown in ambition.

The 2016 and 2017 bleaching events wiped out half the shallow-water corals and the next year, coral reproduction dropped by nearly 90 per cent.

"Dead corals don't make babies," Professor Terry Hughes from James Cook University said at the time.

The reef's return

Despite the 2020 bleaching event, the reef has been in a period of recovery since 2019, and the most fast-growing (but also most fragile) corals have boomed, and coral cover in many parts of the reef has today returned to levels not seen since the 1980s.

Great Barrier Reef in 'recovery window'.
But it could be short lived

The Great Barrier Reef is experiencing a rare window of recovery due to a break in weather and bleaching events according to the latest observations from marine scientists. Read more

But the repeated insults have changed the reef, and left it more vulnerable. Those fast-growing corals make up a much greater percentage of the overall cover, and are much more vulnerable to storms, bleaching and predation.

"Because of these vulnerabilities and likelihood of more climate-related severe weather events, future disturbances may result in rapid decline on these reefs," said Dr Mike Emslie from the Australian Institute of Marine Science when their long-term monitoring results were released this month. 

Through all this, the official outlook for the reef remains "very poor".

And according to the federal government's Great Barrier Reef Authority: "The window of opportunity to improve the Reef's long-term future is now." 

Environment Minister Sussan Ley with Prime Minister Scott Morrison. (AAP)

Despite all that, Australia again avoided the embarrassment of a listing this year.

But without Australia taking international leadership on climate change, it's hard to see how it will be avoided in the years to come.

UNESCO has said that Australia's plan for the reef needed to include actions to address climate change, which are in line with the Paris Agreement, which involves trying to stop climate change at 1.5C of warming.

That makes sense, because even at 1.5C of warming, up to 90 per cent of the world's corals could be lost.

And for Australia's targets to be consistent with the agreement, Australia will need to nearly triple its ambition for 2030.

All that certainly sounds like "danger" for the reef.

Links

• Great Barrier Reef in 'recovery window' after year without major heatwaves, cyclone disturbances
• Government 'blindsided' by move to list Great Barrier Reef as 'in danger'
• (AU The Guardian) Coalition Believes It Has Numbers To Stop Great Barrier Reef Being Listed As ‘In Danger’
• (AU ABC) Great Barrier Reef In 'Recovery' But Experts Say Progress Will Be Threatened By Climate-Related Disturbances
• (AU The Guardian) ‘Fossil Fuel Friends’: Saudi Arabia And Bahrain Back Australia’s Lobbying On Great Barrier Reef
• (AU SMH) Coalition Fighting To Stop Great Barrier Reef Being Declared ‘In Danger’
• Barrier Reef: Ley Stunned By 22 Years Of Warnings
• (AU The Age) ‘UNESCO Was Right’: Global Experts Back Barrier Reef Danger Warning

(AU RenewEconomy) Australia Lifted Fossil Fuel Subsidies More Than Any G20 Nation, Says BNEF

RenewEconomy - Joshua S Hill

Australia’s financial support of fossil fuels increased by 48% over the five-year period between 2015 and 2019, the biggest increase in fossil fuel subsidies among G20 nations, and putting the country well behind its peers in supporting the goals of the Paris Agreement.

A new report from BloombergNEF (formerly Bloomberg New Energy Finance), called the Climate Policy Factbook, shows that Australia – along with a number of other G20 countries – is failing to keep up with even the bare minimum of climate action necessary.

Australia, it says, is lagging in all three areas highlighted in the report – the phasing out support for fossil fuels, putting a price on carbon emissions, and making companies disclose the risks they face due to climate change.

Moreover, while the report graciously describes Australia’s response to carbon pricing and climate-risk disclosure as “mixed”, it is Australia’s continued financial support for fossil fuel projects which draws the biggest concern, categorised in the report as heading in the “Wrong direction”.

According to BloombergNEF’s figures, Australian financial support for fossil fuels between 2015 and 2019 grew by 48% – the largest increase amongst all G20 nations, totalling $US38 billion ($A52 billion).

In 2019, that translated into a fossil fuel subsidy of $293 per person. And while the share of financial fossil fuel support spent on coal was zero in 2019, this just meant there was more left over to go towards oil and gas consumers.

Tax breaks formed the lion’s share of Australia’s financial fossil fuel support thanks to capex deductions for mining and petroleum operations, fuel-tax credits, reduced fuel-excise rates, and offset schemes.

Bloomberg’s report was less critical of Australia’s positions on both carbon pricing and climate-risk disclosure, but in both instances, there remains significant room for improvement.

Bloomberg says the Safeguard Mechanism “lacks ambition … as it was not designed to cut emissions – just ensure they remain below the baseline.”

And while the Australian Government has scrapped a real carbon price on industry and power generation – claiming such a mechanism would damage business – Australian businesses are nevertheless voluntarily ramping up their own investments to offset carbon emissions.

According to figures published earlier this month by market analyst RepuTex, Australia’s carbon market has grown by 21% in the first six months of 2021, with the spot price rising to $20 a tonne – and expected to increase further to over $50 a tonne by 2030.

Australia’s lacklustre, and at times blatantly obtuse climate action, is unfortunately not an outlier. Bloomberg’s latest Climate Policy Factbook shows that, together, the G20 provided $US636 billion ($A870 billion) in direct support for fossil fuels in 2019 alone – only 10% below 2015 levels.

During the report’s timeframe, eight G20 countries increased their support for fossil fuels – notably Australia, Canada, and the United States – “encouraging the use and production of fossil fuels, distorting prices, and risking carbon ‘lock-in’ – where assets funded today continue to emit high levels of emissions for decades ahead.” To make matters worse, five countries allocated over $US1 billion to coal in 2019.

 

Over the five-year period covered in the Factbook, G20 governments provided $US3.3 trillion worth of direct support for coal, oil and gas, and fossil-fuelled power – an amount which, at today’s prices, could have funded 4,232GW worth of new solar plants.

China, unsurprisingly, provided nearly a quarter of the 2019 financial support for fossil fuels, but by a per-capita accounting was nevertheless well below the G20 average – with China’s fossil fuel support working out to $104 per capita compared to the G20 average of $313 per capita.

In contrast, Saudi Arabia’s support for fossil fuels per capita led the way at $1,962, followed by Argentina well back at $734 and Russia at $523.

“Given that the G-20 accounts for nearly three-quarters of global emissions, progress from those governments in these three areas would mark a huge step forward toward tacking climate change,” said Victoria Cuming, head of global policy at BloombergNEF and lead author of the Factbook.

“So far, they have yet to step up to the plate.”

Links

• New Report Finds G-20 Member Countries Support Fossil Fuels at Levels Untenable to Achieve Paris Agreement Goals
• Climate Policy Factbook (pdf)
• Corporate Australia sets its own carbon price amid global dash to net zero
• Seven years after carbon price was scrapped, Australia’s policies still baked in denial
• PM’s climate ambition heats up investment in Australia’s carbon market
• (The Conversation) Global Evidence Links Increase In Extreme Precipitation To Climate Change
• (Al Jazeera) The Climate Crisis Is A Crime Story
• (AU The Guardian) Australian Resources Minister Attacks ‘Green Activists’ For Trying To ‘Cripple’ Fossil Fuel Companies

(Reuters) From China To Germany, Floods Expose Climate Vulnerability.

Reuters - Aradhana Aravindan | James Mackenzie

An aerial view shows a flooded road section following heavy rainfall in Zhengzhou, Henan province, July 21. China Daily via REUTERS/File Photo

Deadly floods that have upended life in both China and Germany have sent a stark reminder that climate change is making weather more extreme across the globe.

At least 25 people in the central Chinese province of Henan died on Tuesday, including a dozen trapped in a city subway as waters tore through the regional capital of Zhengzhou after days of torrential rain. read more

Coming after floods killed at least 160 people in Germany and another 31 in Belgium last week, the disaster has reinforced the message that significant changes will have to be made to prepare for similar events in future. read more

"Governments should first realize that the infrastructure they have built in the past or even recent ones are vulnerable to these extreme weather events," said Eduardo Araral, associate professor and co-director, Institute of Water Policy, at Singapore's Lee Kuan Yew School of Public Policy.

In Europe, climate change is likely to increase the number of large, slow-moving storms that can linger longer in one area and deliver deluges of the kind seen in Germany and Belgium, according to a study published June 30 in the journal Geophysical Research Letters.

As the atmosphere warms with climate change, it also holds more moisture, which means that when rainclouds break, more rain is released. By the end of the century, such storms could be 14 times more frequent, the researchers found in the study using computer simulations.

While the inundation that devastated wide swathes of western and southern Germany occurred thousands of kilometres from the events in Henan, both cases highlighted the vulnerability of heavily populated areas to catastrophic flooding and other natural disasters.

"You need technical measures, bolstering dikes and flood barriers. But we also need to remodel cities," said Fred Hattermann at the Potsdam Institute for Climate Impact Research. He said there was increasing focus on so-called "green-adaptation" measures, like polders and plains that can be flooded, to stop water running off too fast.

"But when there's really heavy rain, all that may not help, so we have to learn to live with it," he said.

Reinforcing dikes and climate-proofing housing, roads and urban infrastructure will cost billions. But the dramatic mobile phone footage of people struggling through subways submerged in chest-deep water in Zhengzhou or crying in fear as mud and debris swept through medieval German towns made clear the cost of doing nothing.

A man looks on outside a house in an area affected by floods caused by heavy rainfalls in Bad Muenstereifel, Germany, July 19, 2021. REUTERS/Wolfgang Rattay/File Photo

"It is shocking and I have to say it is scary," said John Butschkowski, a Red Cross driver who was involved in rescue work in western Germany this week. "It is ghostly, no people anywhere, just rubbish. And it is inconceivable that this is happening in Germany."

Tens of thousands of people were being evacuated from flood-hit regions of central China as officials raised the death toll from heavy rain that has deluged Henan province for almost a week to 33 people. More photos: https://t.co/sjPjFGIQGi pic.twitter.com/0V2AbpLwsJ

— Reuters Pictures (@reuterspictures) July 22, 2021

One year's rainfall in three days

Koh Tieh-Yong, a weather and climate scientist at Singapore University of Social Sciences, said an overall assessment of rivers and water systems would be needed in areas vulnerable to climate change, including cities and farmlands.

"Floods usually occur due to two factors combined: one, heavier-than-normal rainfall and two, insufficient capacity of rivers to discharge the additional rainwater collected," he said.

In both China and northwestern Europe, the disasters followed a period of unusually heavy rain, equivalent in the Chinese case to a year's rainfall being dumped in just three days, that completely overwhelmed flood defences.

Residents, holding umbrellas amid heavy rainfall, wade through floodwaters on a road in Zhengzhou, Henan province, July 20. cnsphoto via REUTERS/File Photo

After several severe floods over recent decades, buffers had been strengthened along major German rivers like the Rhine or the Elbe but last week's extreme rainfall also turned minor tributaries like the Ahr or the Swist into fearsome torrents.

In China, built-up urban areas with inadequate water evacuation and large dams that modified the natural discharge of the Yellow River basin may also have contributed to the disaster, scientists said.

Rescuers carry children to safety in flood-stricken Anyang

But measures such as improving the resilience of buildings and raising riverbanks and improving drainage are unlikely to be enough on their own to avert the effects of severe flooding. As a last resort, warning systems, which were heavily criticized in Germany for leaving people insufficient time to react, will have to be improved.

"It really needs to be embedded in practical knowledge that people have so they know what to do," said Christian Kuhlicke, head of a working group on environmental risks and extreme events at the Helmholtz Centre for Environmental Research.

"If you can't keep the water back, if you can't save your buildings then at least make sure that all vulnerable people are moved out of these places."

Links

• How Deadly Flooding in Germany and Belgium Exposed Europe's Climate Change Hubris
• China’s Drowned City Is a Bleak Sign of a Changing Climate
• Climate scientists shocked by scale of floods in Germany
• Death toll rises and thousands flee homes as floods hit China
• How climate change fueled the devastating floods in Germany and northwest Europe
• 'Once in a thousand years' rains devastated central China, but there is little talk of climate change
• European Floods Are Latest Sign of a Global Warming Crisis
• German Floods Shake Up Campaign as Climate Change Hits Home

(UK The Guardian) John Kerry: World Leaders Must Step Up To Avoid Worst Impacts Of Climate Crisis

The Guardian - Fiona Harvey

US envoy uses landmark speech in London to make impassioned plea for unified global effort

‘The climate crisis is the test of our times’: John Kerry speaks at Kew Gardens – video

The world still has a chance of staving off the worst impacts of climate breakdown but only if governments step up in the next few months with stronger commitments on cutting greenhouse gas emissions, the US envoy for climate change has said.

John Kerry, appointed by Joe Biden to spearhead the US’s international efforts to tackle the crisis, urged all large economies to come forward with new plans to cut emissions before the Cop26 UN climate talks in Glasgow this November.

“The climate crisis is the test of our own times and, while it may be unfolding in slow motion to some, this test is as acute and as existential as any previous one. Time is running out,” he said.

He called Cop26 “a pivotal moment” and 2021 “a decisive year”, as the world must get to grips with the climate crisis and rapidly slash emissions in the 2020s to have a chance of a safe future.

Speaking as floods have devastated parts of Europe and heatwaves and wildfires swept North America, Kerry drew a parallel between the ruins of Europe after the second world war and the ravages of the climate crisis.

“The world order that exists today didn’t just emerge on a whim. It was built by leaders and nations determined to makes sure that never – never – again would we come so close to the edge of the abyss,” he said.

US seeks cooperation with China on climate but not at any price. Read more

Kerry said his earliest memory, aged four, was of the ruined skeleton of a burned-out building in Europe, where he had been taken by his mother, who fled the Nazis.

“That journey has always given me the bedrock confidence that we can solve humanity’s biggest threats together.”

Staying within 1.5C of global heating, the aspirational goal of the 2015 Paris climate agreement, was still possible, he insisted.

“There is still time to put a safer 1.5C future back within reach. But only if every major economy commits to meaningful absolute reductions in emissions by 2030. That is the only way to put the world on a credible track to global net zero by mid-century,” he said.

The Paris agreement targets an upper limit of holding global temperature rises to well below 2C above pre-industrial levels, with an aspirational lower limit of 1.5C.

Kerry made it clear that the Cop26 summit must aim for the lower threshold, and warned that current government pledges on emission cuts would lead to 2.5C or 3C rises.

“We’re already seeing dramatic consequences with 1.2C of warming. To contemplate doubling that is to invite catastrophe,” he said.

Kerry used his landmark speech at the Royal Botanic Gardens, Kew, in London, with just over 100 days to go before Cop26, to make an impassioned plea for a unified global effort. “We can’t afford a world so divided in its response to climate change when the evidence for compelling action is so strong.”

He singled out China, the world’s biggest emitter and second largest economy, which has yet to submit to the UN a national plan for emissions cuts before 2030. “It’s imperative that we and China, and the rest of the world, are pulling in the same direction on this critical effort,” he said.

Kerry told the Guardian in an interview after his speech that he was hopeful China would realise the need to act quickly. “When China has set targets before, it has outperformed them, so that is very hopeful,” he said.

But he made it clear he also had other countries in his sights. He said the US was working with “allies, partners, competitors and even adversaries all too aware that some things happening today threaten to erase the very progress so many are struggling to advance”.

UN climate summits proceed by consensus so recalcitrant counties can thwart agreement. For Cop26 to be a success, countries such as Russia, Brazil and Saudi Arabia will need to acquiesce at least – Kerry’s remarks will be seen as warning them not to disrupt the process.

Climate experts and campaigners told the Guardian the US was still lagging behind in providing finance for poor countries, to help them cut emissions and cope with the impacts of extreme weather. Rich countries promised a decade ago to provide at least $100bn a year in climate finance by 2020, a pledge that has not been met.

“The US is not pulling its weight – it’s the only country holding up the $100bn pledge,” said John Sauven, executive director of Greenpeace UK. “If the US does not put its hands in its pockets and make up the shortfall, Glasgow will be in jeopardy.”

Kerry told the Guardian in response that the Biden administration was “working hard” on finding more financial assistance for poor countries. “It’s very important that the US should provide finance. Our internal process on this is not complete yet.”

He added: “We are very conscious of the sensitivities around this. The US obviously plays a key role, and our absence in the last four years [from climate action] heightens that sense of responsibility and the imperative to find a way.”

Ed Miliband, the shadow business secretary, who was at the speech – which no government ministers attended – said Kerry had shown the US was determined to lead the way on climate action. “He made it clear he is focused on 1.5C – and he’s absolutely right, that’s ambitious but essential,” he said.

Kerry also called on governments to invest in clean energy, holding out the prospect of a clean energy boom worth $4tn a year by 2030, and said new technologies such as hydrogen and carbon capture and storage would also be needed.

Links

• John Kerry Says Climate Change Is An 'Existential' Crisis
• John Kerry commits US to climate crisis fight but warns world is way off pace
• John Kerry on climate change and the economic transformation to come 
• Solving climate change will require "technologies we don't yet have" says John Kerry
• Climate change as a national security issue
• Will America Finally Lead on Climate?

(ABC) No Scientific Consensus Yet On Whether Warming Arctic May Lead To More Extreme Weather

 ABC Weather - Ben Deacon

Predicting the impact of global warming on the jet stream is at the frontier of climate science. (Supplied: NASA)

Key Points Climate change is leading to an increase in the frequency and intensity of extreme weather events The warming Arctic may be leading to a slowing of the jet stream in the Northern Hemisphere, causing more extreme weather The slowing jet stream theory is an area of ongoing research

In the past month alone, Germany, Belgium and the Netherlands have suffered horrific flooding, Siberia caught fire, and the Arctic Sea suffered near-record melting. 

 Meanwhile, in North America, after record-high temperatures, formerly rare fire thunderstorms have become near-daily events.

There is one big theory connecting climate change to the weather patterns behind events as disparate as fire and floods, heatwaves and melting ice, across three different continents. 

It is elegant, reasonably easy to understand and has profound implications — but because it is at the frontier of climate science, not all researchers are yet convinced.

Warmer world, hotter heatwaves

 In one respect, the influence of climate change on heatwaves is relatively straightforward, according to Andrew King from the ARC Centre of Excellence for Climate Extremes at The University of Melbourne.

Smoke from Oregon's Bootleg fire rises behind the town of Bonanza. (AP: Bootleg Fire Incident Command)

"We've warmed the planet by about 1.2 degrees Celsius and the land has warmed faster than the ocean," Dr King said.

"So, this allows heatwaves to be that bit hotter than they would be otherwise."

Lytton, in Canada's British Columbia, recorded a record high temperature of 49.6C on June 29. (Supplied: Andybremner2012 CC BY-SA 4.0)

 Dr King said a warmer atmosphere could also hold about 7 per cent more moisture for every degree Celsius of warming.

"That means storms that occur on very short timescales can rain out more than they would be able to in a world without global warming," he said.

Heavy rainfall in central China's Henan province caused deadly flooding this week. (Supplied: AP)

Climate change and weather patterns

Instances of extreme weather can be driven by distinct weather patterns that allow rain or heat to build up over time because weather systems stall in one place instead of moving on.

If climate change is causing weather systems to stall for longer, they may build to more intense levels.

This visualisation of high-altitude winds over North America on the day it reached 49.6 degrees Celsius in Canada shows the meandering jet stream. (Supplied: Earth.nullschool.net)

Late last month in Canada, a horseshoe-shaped high-pressure system called an Omega Block saw heat build up for days, leading to off-the-chart temperatures. In Europe last week, a cut-off low pressure system stalled over Germany, dumping a month's worth of rain in a day.

The jet stream pattern which led to the catastrophic #EuropeFloods pic.twitter.com/VXH7MlGU5u

— Stu Ostro (@StuOstro) July 19, 2021

Limit of science

The impact of climate change on how such individual weather patterns move is at the very limit of science.

"It's kind of like having a jigsaw but most of the pieces are missing," Dr King said.

"We have really incomplete observations in many parts of the world and they don't go back long enough in time to really track the climate for long enough."

A lack of weather observations from remote regions like the Arctic makes it difficult to predict the precise behaviour of weather systems. (Supplied: Polar Bears International)

That missing data — often from remote places like the Arctic — is needed to build computer models of unprecedented detail that can better predict weather patterns. 

"We really need high-resolution simulations," Dr King said. 

"We have a few studies with regional, high-resolution simulations that point to a climate change-caused intensification of short-duration extreme rainfall, including in Europe.

"That's quite a powerful line of evidence to suggest that climate change is [enhancing] — or has likely enhanced — the recent extreme rainfall we saw in Germany, the Netherlands and elsewhere.

"But we just don't have enough data to really make conclusive statements."

The missing data is crucial to answering one of the biggest questions in climate science: Are weather systems sticking around for longer in the Northern Hemisphere because of climate change?

The answer — which would connect heat, floods and fire — has everything to do with the jet stream.

The jetstream circling the North Pole, reaching down into North America.

Wavy jet stream theory

Dr King says there is a belt of high-altitude winds that encircle the Northern Hemisphere, called the jet stream, and weather systems often follow that track.

Those winds are related to temperature differences between the cold polar regions and the warm tropics. 

"In a warming world, we're seeing a bit more warming over higher latitudes in the polar regions than we see over the equator," Dr King said.

"And that reduces the temperature difference between the equator and the poles.

"The idea is that, if you reduce that temperature difference between the equator and the poles, both near the surface and higher up in the atmosphere, you might reduce the strength of the jet stream. And you might make it wavier or slower," he said.

A slower, wavier jet stream may allow storms to stick around longer, leading to more extreme weather. 

But there is no conclusive evidence that the jet stream is slowing due to climate change.

"There are a variety of studies looking into this, some of which find evidence to suggest this is happening, particularly from the model-based studies, [and[ others, which suggest this isn't really happening,"  Dr King said. 

How the warming Arctic affects weather patterns in the Northern Hemisphere is an active area of research. (Supplied: Alfred-Wegener-Institut/Mario Hoppmann)

One recent study used detailed computer modelling to show a warmer world would lead not only to more intense rain in Europe but also to slower storm movement. 

However, its lead author — Abdullah Kahraman from Newcastle University in the United Kingdom — was at pains to qualify the limits of the study, saying it related to one very detailed computer simulation.

"This study does not really tell you that this will definitely be happening like that, because this is one scenario," Dr Kahraman said.

"However, when it comes to the jet stream issue, this is not the only simulation that is projecting some kind of decreasing of wind speed in the higher atmosphere."

Other scientists have recently shown there may only be a modest decrease in high altitude winds due to a warming Arctic. 

"It's basically an area of very active research, there are quite a few people around the world looking into this. And there is a diversity of views among scientists," Dr King said.

"At the very least, I think we can say that we don't have a great deal of confidence that this is a clear effect of climate change.

"But there is some indication that there might be more persistence of weather systems, as the jet stream may be allowing them to remain in place for longer.

"This could be contributing to some extreme weather events."

Links

• Then and now: Arctic sea-ice feeling the heat
• Arctic’s ‘Last Ice Area’ May Be Less Resistant to Global Warming
• As Arctic warms, scientists wrestle with its climate ‘tipping point’
• The Arctic is in a death spiral. How much longer will it exist?
• Climate explained: why is the Arctic warming faster than other parts of the world?
• What climate change is doing to the Arctic Ocean
• 2020 Arctic Sea Ice Minimum at Second Lowest on Record 
• 2020 Arctic air temperatures continue a long-term warming streak

(USA TODAY) Scientists Discover More Than 30 Viruses Frozen In Ice, Most Never Seen Before

USA TODAY - Jordan Mendoza

Ancient, 15,000-year-old viruses identified from melting glaciers

What will happen when these ancient, ice-bound viruses thaw out? Buzz60

A group of scientists discovered ancient viruses frozen in two ice samples taken from the Tibetan Plateau in China, and most of them are unlike anything ever seen before.

The findings, published Wednesday in the journal Microbiome, came from ice cores taken in 2015 that scientists believe began to freeze at least 14,400 years ago.

“These glaciers were formed gradually, and along with dust and gases, many, many viruses were also deposited in that ice," lead author and researcher at The Ohio State University Byrd Polar and Climate Research Center Zhi-Ping Zhong said in a statement.

"The glaciers in western China are not well-studied, and our goal is to use this information to reflect past environments. And viruses are a part of those environments."

When researchers analyzed the ice, they found genetic codes for 33 viruses.

Of the 33 found, genetic codes for four of them showed they are part of virus families that typically infect bacteria. However, up to 28 of the viruses were novel, meaning they had never before been identified.

However, the group doesn't believe the viruses originated from animals or humans, but came from the soil or plants. The scientists also believe roughly half of them survived because of the ice.

"These are viruses that would have thrived in extreme environments,” said Matthew Sullivan, co-author of the study and director of Ohio State’s Center of Microbiome Science.

“These viruses have signatures of genes that help them infect cells in cold environments – just surreal genetic signatures for how a virus is able to survive in extreme conditions."

Sullivan added the technology used to study microbes and viruses inside the ice would eventually lead to looking for similar genetic sequences in other extreme ice environments, possibly on Mars.

Senior author of the study Lonnie Thompson said the discovery of the viruses in glaciers of ice will also help researchers understand how they respond to climate change.

“We know very little about viruses and microbes in these extreme environments, and what is actually there,” Thompson said. “The documentation and understanding of that is extremely important."

Links

• Glacier ice archives nearly 15,000-year-old microbes and phages
• 15,000-year-old viruses discovered in Tibetan glacier ice
• Climate Change And Infectious Diseases (pdf)
• Fact check: Yes, viruses can mutate to become more deadly
• How Climate Change Is Contributing to Skyrocketing Rates of Infectious Disease
• How might climate change affect the spread of viruses?