29/07/2019

Human-Caused Global Heating Breaks Clear From Nature, Studies Find

Sydney Morning HeraldPeter Hannam

Global heating in recent decades is of a pace and magnitude that's unique in at least the past two millennia, with human-caused climate change now "overwhelming" natural variability, new research has found.
According to three papers published in Nature and Nature Geoscience on Thursday, international teams of scientists used seven different statistical techniques to reconstruct global temperature during the so-called Common Era starting 2000 years ago.


A new report claims that Earth's rapid warming in the late 20th century was far more widespread than any temperature variations during the previous 2,000 years.

The scientists studied variability over decades and centuries, including well-known periods of shifting temperatures such as the Medieval Warming Period and the Little Ice Age. They found no era had the spatial extent or intensity of the heating over recent decades.
"Periods of warming and cooling have happened in the past but they were nowhere near the magnitude or the speed of the current warming," said Benjamin Henley, a University of Melbourne researcher and co-author of one of the papers. "The main, overwhelming impact on the climate has been in the recent decades, since about 1950."
The papers build on a major global effort to reconstruct past climate using a range of data sources, such as tree rings and coral cores, that was published in 2017.
Dr Henley said the new research revealed "incredible consistency" across different methods, adding to the confidence that current models can predict the future climate as greenhouse gas emissions continue to rise.
Global warming/cooling rates over the past 2,000 years
Source: Benjamin Henley/Nature
The work also further debunks the claims of climate change deniers who often point to periods such as the Little Ice Age as evidence the climate is in constant flux. Rather, unusual conditions were typically confined to regions.
For example, while north-western Europe experienced a cold spell in the 17th century - as widely depicted in paintings of frozen rivers such as England's Thames - the central and eastern Pacific experienced the chill in the 15th century.
"By contrast, we find that the warmest period of the past two millennia occurred during the 20th century for more than 98 per cent of the world," another of the papers said.
German police find a new use for their water cannons amid record-breaking heat in that country on Wednesday. Those heat records, though, may last just one day. Credit: DPA


Volcanic influence
Interestingly, volcanoes were found to be the dominant influence for most of the Common Era, potentially masking the start of the impact of the Industrial Revolution on global conditions.
Volcanic particles pumped high into the atmosphere typically cause widespread cooling followed by a warming rebound as they dispersed over time.
Several large tropical volcanic eruptions within three decades of the first half of the 19th century triggered "substantial drops of summer temperatures over the Northern Hemisphere land areas", the third paper found.
"Only after the 1850s did the transition into the period of anthropogenic warming start," it stated.
For Michael Mann, the director of Penn State University's Earth System Science Centre, the papers offer fresh vindication of work he led two decades ago in the so-called "Hockey Stick" studies. These revealed the relatively recent ramping up of global temperatures.
"We’re pleased that decades after our original work, independent, international teams of scientists using entirely different approaches, and more widespread now-available paleoclimate data, have come to virtually identical conclusions to those we offered in our original work," Professor Mann told the Herald and The Age.
These included that past climate episodes such as the Medieval Warm Period of about three centuries after 950 CE and the Little Ice Age "were far more regional in nature than the globally-pervasive warming of the past century", he said.
A second conclusion reaffirmed was that the current warmth at global and hemispheric scales "is unprecedented as far back as the estimates go - now more than 2000 years", Professor Mann said.
Heatwaves are just one of the extreme weather events that getting worse with climate change. Credit: Cole Bennetts

Heatwaves only part of the problem
The papers' release coincided recent heatwaves that have baked Europe - including setting records on Wednesday in several countries, with more expected on Thursday - and North America during their current summers.
Global temperatures in June were the hottest in more than a century of data, the US National Oceanic and Atmospheric Administration reported last month. July is on course to set global records too.
For Dr Henley, though, heatwaves are temporary and, while among the clearest signals of global warming, are still weather-related.
"The far bigger concern is the long term and the far bigger changes we are making to the climate system," he said, noting effects ranging from more severe flooding and droughts, and rising sea levels.
"It’s more the cumulative impacts on the human system and the natural system," Dr Henley said. "Many of the ecosystems we have on earth won’t be able to handle the pace of change."

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The Guardian Joins A Major Media Initiative To Combat The Climate Crisis

The Guardian

More than 60 news outlets worldwide have signed on to Covering Climate Now, a project to improve coverage of the emergency
Student protestors march during a ‘Fridays for Future’ demonstration against climate change in Berlin, Germany, 19 July 2019. Photograph: Felipe Trueba/EPA
For a week this September, dozens of news organizations in the US and around the world will join forces to devote their front pages and airwaves to a critical but under-covered story: the global climate emergency.
This unique media collaboration, timed to coincide with landmark UN Climate Action Summit in New York, is the first initiative of Covering Climate Now, a project co-founded by The Nation and the Columbia Journalism Review, in partnership with The Guardian, which aims to kickstart a conversation among journalists about how news outlets can improve their coverage of the climate crisis.
The project, which is still welcoming additional media partners, announced an initial list of more than 60 partners today, representing every corner of the media landscape, all of whom have pledged to dedicate resources to climate coverage for the week starting 16 September and leading up to the UN Summit on 23 September. The partners include major TV networks (CBS News) , digital players (HuffPost, Vox, the Intercept, Slate), local newspapers (the Philadelphia Inquirer, the Minneapolis Star Tribune), public radio programs (Marketplace, The World) and many others.
Covering Climate Now launched in May at an event at Columbia Journalism School with dozens of newsroom leaders, including the legendary TV journalist Bill Moyers, who delivered the keynote. At the time, the co-founders of Covering Climate Now, Mark Hertsgaard of the Nation and Kyle Pope, editor-in-chief of Columbia Journalism Review, wrote an impassioned oped calling for change in how the media covers the climate crisis.
“At a time when civilization is accelerating toward disaster, climate silence continues to reign across the bulk of the US news media,” Hertsgaard and Pope wrote. “Especially on television, where most Americans still get their news, the brutal demands of ratings and money work against adequate coverage of the biggest story of our time.”
Partners in the September week of coverage will make their own editorial decisions about what stories to feature. All that’s required is for each outlet to make a good faith effort to increase the amount and the visibility of its climate coverage – to make it clear to their audiences that climate change is not just one more story but the overriding story of our time. The point is to give the climate story the attention and prominence that scientists have long said it demands so that the public and policymakers can make wise choices.
You can read more about the initiative here.

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Extreme Weather Caused By Climate Change Has Damaged 45% Of Australia’s Coastal Habitat

The ConversationRuss Babcock | Anthony Richardson | Beth Fulton | Eva Plaganyi | Rodrigo Bustamante
Bleached staghorn coral on the Great Barrier Reef. Many species are dependent on corals for food and shelter. Damian Thomson, Author provided
If you think climate change is only gradually affecting our natural systems, think again.
Our research, published yesterday in Frontiers in Marine Science, looked at the large-scale impacts of a series of extreme climate events on coastal marine habitats around Australia.
We found more than 45% of the coastline was already affected by extreme weather events caused by climate change. What’s more, these ecosystems are struggling to recover as extreme events are expected to get worse.
There is growing scientific evidence that heatwaves, floods, droughts and cyclones are increasing in frequency and intensity, and that this is caused by climate change.

Life on the coastline
Corals, seagrass, mangroves and kelp are some of the key habitat-forming species of our coastline, as they all support a host of marine invertebrates, fish, sea turtles and marine mammals.
Our team decided to look at the cumulative impacts of recently reported extreme climate events on marine habitats around Australia. We reviewed the period between 2011 and 2017 and found these events have had devastating impacts on key marine habitats.
Healthy kelp (left) in Western Australia is an important part of the food chain but it is vulnerable to even small changes in temperature and particularly slow to recover from disturbances such as the marine heatwave of 2011. Even small patches or gaps (right) where kelp has died can take many years to recover. Russ Babcock, Author provided









These include kelp and mangrove forests, seagrass meadows, and coral reefs, some of which have not yet recovered, and may never do so. These findings paint a bleak picture, underscoring the need for urgent action.
During this period, which spanned both El Niño and La Niña conditions, scientists around Australia reported the following events:

Extreme climate events impact on marine habitats in Australia

Heritage areas affected
Many of the impacted areas are globally significant for their size and biodiversity, and because until now they have been relatively undisturbed by climate change. Some of the areas affected are also World Heritage Areas (Great Barrier Reef, Shark Bay, Ningaloo Coast).
Seagrass meadows in Shark Bay are among the world’s most lush and extensive and help lock large amounts of carbon into sediments. The left image shows healthy seagrass but the right image shows damage from extreme climate events in 2011. Mat Vanderklift, Author provided







The habitats affected are “foundational”: they provide food and shelter to a huge range of species. Many of the animals affected – such as large fish and turtles – support commercial industries such as tourism and fishing, as well as being culturally important to Australians.
Recovery across these impacted habitats has begun, but it’s likely some areas will never return to their previous condition.
We have used ecosystem models to evaluate the likely long-term outcomes from extreme climate events predicted to become more frequent and more intense.
This work suggests that even in places where recovery starts, the average time for full recovery may be around 15 years. Large slow-growing species such as sharks and dugongs could take even longer, up to 60 years.
But extreme climate events are predicted to occur less than 15 years apart. This will result in a step-by-step decline in the condition of these ecosystems, as it leaves too little time between events for full recovery.
This already appears to be happening with the corals of the Great Barrier Reef.

Gradual decline as things get warmer
Damage from extreme climate events occurs on top of more gradual changes driven by increases in average temperature, such as loss of kelp forests on the southeast coasts of Australia due to the spread of sea urchins and tropical grazing fish species.
Ultimately, we need to slow down and stop the heating of our planet due to the release of greenhouse gases. But even with immediate and effective emissions reduction, the planet will remain warmer, and extreme climatic events more prevalent, for decades to come.
Recovery might still be possible, but we need to know more about recovery rates and what factors promote recovery. This information will allow us to give the ecosystems a helping hand through active restoration and rehabilitation efforts.
We will need new ways to help ecosystems function and to deliver the services that we all depend on. This will likely include decreasing (or ideally, stopping) direct human impacts, and actively assisting recovery and restoring damaged ecosystems.
Several such programs are active around Australia and internationally, attempting to boost the ability of corals, seagrass, mangroves and kelp to recover.
But they will need to be massively scaled up to be effective in the context of the large scale disturbances seen in this decade.
Mangroves at the Flinders River near Karumba in the Gulf of Carpentaria. The healthy mangrove forest (left) is near the river while the dead mangroves (right) are at higher levels where they were much more stressed by conditions in 2016. Some small surviving mangroves are seen beginning to recover by 2017. Robert Kenyon, Author provided


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'I’m Seeing It Disappear Before My Eyes': Crisis Point In Australia's Wet Tropics

Sydney Morning HeraldDeborah Snow

Last summer, in November, Queensland biologist Professor Stephen Williams was at a workshop in Vietnam when he received an urgent email from home. It was from a ranger he knew who worked for the World Heritage-listed wet tropics area around Cairns.
Something unprecedented was happening at the top of Mount Bartle Frere, North Queensland’s highest peak. At 1611 meters high, the mountain’s upper reaches are in what is meant to be a cool temperate zone.
Upland rainforest on Mount Windsor, part of the Wet Tropics World Heritage Area. Credit: Kerry Trapnell
But instead of normal summer readings at the peak, which rarely top 25, temperatures had soared past 35 degrees for six days in a row, culminating in one scorcher of 39.
“This is on a mountain where the average temperature for the year is usually 12 degrees, a nice warm day is around 18, and a hot day is 25,” Williams tells me, as we sit in a cafe high up on the nearby Atherton tableland. “I was shocked, and very worried about the impact. Temperatures like this were unheard of.
”Williams, 57, is Professor of Global Change Biology at James Cook University and a long-time expert on many of the unique animal species which inhabit the ancient rainforests of North Queensland. Along with the spectacular landscape, those animals together with the nearly 700 unique plant species growing in the forests are a fundamental reason why the 900,000 hectare area received much sought-after World Heritage listing in the late 1980s.
"Temperatures like this were unheard of”: Professor Stephen Williams. Credit: Kerry Trapnell
In March, worried about the impact of the November heat wave, Williams carried out a spot check on one of the area’s most iconic and vulnerable creatures, the lemuroid ringtail possum, which he’d been studying for nearly two decades. These creatures are endemic, meaning they live nowhere else except in these high wet tropics pockets. The results were another shock.
At sites where he used to reliably record some 20  individuals an hour, he was now finding only three or four. It was a similar story elsewhere on the mountain slopes and on the higher sections of the tableland. Williams alerted the Wet Tropics Management Authority (an agency jointly reporting to the federal and Queensland governments) which called an emergency board meeting a week later. Within days, in late April, the board had issued its most chilling warning yet about the impact of climate change on the iconic area.
“The Board … has now become aware that, following the hottest summer ever recorded, some of the key species for which the Wet Tropics World Heritage Area was listed are at imminent risk of extinction,” it warned.
“Professor Williams’ recent monitoring has identified that the declines in possum and bird species … are now reaching alarming levels. If the trends continue, populations at sites that previously had the highest density of lemuroid ringtail possums could become locally extinct as early as 2022.”

'The canary in the coal mine'
Searching for possums at Mount Hypipamee National Park. Credit: Kerry Trapnell
On a chilly Monday evening this week, the Herald and The Age accompanied Williams to a site at Mount Hypipamee National Park, 950 meters above sea level up behind Cairns, to track down some of the nocturnal creatures.
We tramped in darkness along a track lined with dense rainforest, swinging torches and spotlights up into the tracery of branches overhead, seeking the tell-tale reflection of possum eyes. In an hour or more of searching, Williams had picked out four lemuroids, two Herbert River ringtails and two Green ringtails (also highly vulnerable endemic species). At this site, the numbers were 50 per cent down on what he would expect to find. Elsewhere, he says, numbers are down closer to 70 per cent.
The ringtails, which have evolved to thrive in the cooler upland areas, cannot handle temperatures in excess of 29 or 30 degrees, so the species is drifting ever higher up the mountains, Williams explains. They are disappearing from an elevation of 800 metres which used to be the “sweet spot” for biodiversity. Now they are starting to decline even at 1000 metres. Once they reach the peaks there will be nowhere else for them to go.
Bird species unique to the region are being similarly affected. “It’s distressing,” he says. “This is what I have spent my life working on, and I’m seeing it disappear before my eyes.”
The Wet Tropics world heritage area runs for some 450 kilometres down the coast between Cooktown and Townsville and includes the oldest continuously surviving tropical rainforests on earth. They are, says Leslie Shirreffs, the chair of the Wet Tropics Management Authority, a “living museum”, containing plant ancestors of the great Gondwana forests that covered the continent and parts of Antarctica 50 to 100 million years ago, among them rare species that show how the earliest flowers evolved.
The Wet Tropics (which includes the Daintree in its northern reaches) abuts another globally famous world-heritage site, the Great Barrier Reef.
But while efforts to save the reef – ravaged in some sections by widespread coral bleaching - have drawn the bulk of the funding and the attention, the rainforest remains something of the poor cousin, Shirreffs says. “We had predicted that the loss [of the cool adapted mountain species] would happen on current trajectories by the end of the century. But we are seeing it now,” she says.
Williams says both the reef and the rainforest are being heavily impacted by climate change, but “my problem is that we don’t have such obvious signs that the rainforest is in trouble – we don’t have ‘canopy bleaching’.”
The Australian Conservation Foundation says that makes it harder to galvanise more action for wet tropics protection. “It looks like a beautiful place and it is a beautiful place, but that’s actually one of the problems. It hides pretty well the damage that's being done to it,” explains ACF’s chief executive, Kelly O’Shanassy, who accompanied a small group of journalists to the world heritage site.
The Wet Tropics Authority receives $2.7 million annually from the federal government for its baseline operating costs, but that figure has not increased since 2004 (though funding for specific projects has waxed and waned).
Williams had an extensive monitoring program set up over several years where he was tracking climate change impacts at some 40 sites, taking localised temperature readings. But then, he says, “the money stopped … we left the data loggers out there until they died. Especially in the rainforest that sort of instrument only lasts a few years. We kept them running as long as we could.”
O’Shanassy says people sometimes ask her why they should worry about the threatened disappearance of these highly specialised possum species. “They are the canary in the coal mine, just as much as the reef,” she says. “They are showing us what our future holds …. If we don’t move from burning coal to renewables in the next 10 years, we can’t stop runaway climate change and we will see this vast damage everywhere, including things we humans rely on. We lose the beauty - but we might also lose our life support systems.”

Temperatures soar, with devastating effect
More than 400 orphaned juvenile spectacled flying foxes were brought in for care over the space of just a few days. Credit: Kerry Trapnell
Jenny McLean at her bat hospital. Credit: Kerry Trapnell
Down near the coast, Cairns also suffered record temperatures in November, with a devastating effect on another creature which is iconic for the region: the spectacled flying fox. Thousands were discovered dead or dying as temperatures soared to 42 degrees.
At the bat hospital which Jenny McLean runs at Tolga, on the Atherton tableland above Cairns, more than 400 orphaned juveniles were brought in for care by volunteers over the space of just a few days.
McLean, a small, wiry woman whose been caring for injured bats since 1990 and runs the place on the lean earnings from a modest visitor’s centre, knows as much about the flying foxes as the scientists who regularly visit her. Those bats she can save she nurses back to health in a large enclosure where bright strings of apples hang beneath the open mesh roof like bunting, and nectar bottles hang invitingly for her patients to sip from.
“We are giving them another chance at life,” she says, as she cradles a tiny microbat weighing no more than 8 grams.
Among the scientists who are regular visitors to McLean’s bat refuge is the CSIRO’s flying fox expert, Dr David Westcott.
With McLean’s help, researchers have worked out how to place transmitters on the bats to locate the more remote flying fox camps in the forest, and thus ascertain their numbers more accurately. Westcott says a recent analysis of his data shows that the population has declined dramatically – by an order of around 70 per cent – over the last 14 years.
Dr David Westcott. Credit: Kerry Trapnell
“It looks like the initial declines were driven by cyclones and then the heat stress event [in November] has given them a good whack while they’re already down,” he says. “Our most recent estimate prior to that heat stress event was 80 to 90,000 animals. There is some debate about how many died but it's a significant proportion, 20-plus per cent of the known population.”
It was, he says, the first report of mass die-offs among the creatures because of heat stress. “At 42 degrees they cease to be able to thermo-regulate. They can’t shed the heat.”
The impact of climate change is also being noticed by Aboriginal groups that have traditional ties to the wet tropics.
Among them are the Djabugay people, who have native title over parts of the Barron Gorge National Park, north-west of Cairns. Barry Hunter, project officer for the local Aboriginal corporation, says he’s noticed many changes since he was a boy scrambling up and down the spectacular Barron Gorge waterfall.
“Over the last 20 years, I have seen distinct change, particularly in the birds, some of which have a totemic meaning for family groups.”
Barry Hunter says he’s noticed many changes over the last 20 years. Credit: Kerry Trapnell
Climate change is also disrupting his community’s traditional methods of fire management. “We have not had a dry season this year, which indicates changing weather patterns,” Hunter says. “We should be well and truly into our traditional burning season,” he adds, explaining that setting small mosaic fires helps minimise the risk of massive blazes in areas adjacent to the heritage-listed forests.
The ACF and the federal government remain at loggerheads over whether funding for environmental protection is anywhere near adequate. ACF’s O’Shanassy says since the Coalition came to office in 2013, the environment budget has been cut by nearly 40 per cent, to around $900 million a year.
A spokesman for Scott Morrison’s new Environment Minister, Sussan Ley, flatly rejects that claim, saying ACF ignores programs which are not directed through the department but are environmentally significant. He cites the $190 million National Landcare program, a $137.5 million "practical environment restoration package" and $250 million over the next five years to support management of federal environmental water holdings as examples. This week, a $1.9 million grant under the Landcare program was awarded to an NGO in the wet tropics area.
But the Wet Tropic Authority’s board said in April that investment was “not commensurate with the urgency for mitigating climate change impacts”.
One area where the two sides have reached agreement is over ridding the wet tropics and adjacent rich agricultural land of yellow crazy ants, an introduced species that wreaks devastation on local ecosystems and farmers alike.
This year’s budget set aside $9 million to keep eradication programs going, with the Wet Tropics Authority overseeing much of that spend. It’s painstaking work, as rangers and community volunteers fan out in grid patterns, laying down a paste to lure the ants (cat food mixed with apricot jam works a treat), then coming back to set poison baits at infestation hot spots.
A team works on the eradication of yellow crazy ants, an introduced species. Credit: Kerry Trapnell
Shirreffs says the success of the program is a model for what could be achieved in the bigger battle against climate change. “It has worked by bringing together industry, the community, science and government - they all have an interest in the survivability and integrity of the world heritage area, which is worth $5.2 billion a year to the local economy.”
O’Shanassy, speaking more bluntly, says ACF will try to work around Canberra and partner with business and state governments on climate change because “the Coalition government is not signalling that it’s going to be serious on climate action”.
“The government says we are going to reach our Paris [emissions reduction targets] in a canter? Every bit of evidence says we are not. There are flat-out lies being told which is very distressing because this is a fundamental issue that affects all Australians.”
In a week in which heat records have tumbled in Europe – a week when even mining giant BHP’s boss Andrew Mackenzie has declared climate change to be an “existential” threat – Williams says he wants to see Australia at the forefront of the issue globally.
“Fiddling around at the edges is not going to cut it. We have to tackle the root causes. What most people don’t understand is that this is not something that might happen in the future, it's already happening. All over the word. I’m talking about thousands of studies that demonstrate [the damage] in every ecosystem, from the Artic to the Antarctic.”

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