15/10/2019

Traditional Owners Urge Climate Change Policy Makers To Witness Mangrove Devastation

ABC News - Jane Bardon

Patsy Evans said she was devastated by what she saw when visiting the mangroves of the Gulf of Carpentaria. (ABC News: Jane Bardon)
Key points
  • Scientists have said the severity of the mangrove dieback is on a par with Great Barrier Reef bleaching
  • The Top End is experiencing sea level rise at two to three times global averages
  • The CSIRO is warning the world is not on track to halt sea level rise


Traditional owners are devastated by the lack of recovery at the site of Australia's worst recorded mangrove dieback and are calling for action to limit climate change threats.
Traditional owner Patsy Evans had hoped there would be signs of recovery at the site of the mangrove dieback, in the Gulf of Carpentaria.
But during a recent visit to the area for the first time since 2015, when she and her husband alerted the Northern Territory Government to the extent of the damage, she was devastated by the scene.
"This is bad, worse, it's unbelievable, I can't even believe what's happening here," Ms Evans said.
She said she wanted policy makers to see how climate change was affecting the land near her home on the Limmen River, 750 kilometres south of Darwin.
"Go out and see what's happening, be aware and look at it, and don't make decisions where you are," she said.


The Top End is on the front line of Australia's most severe climate challenges (ABC News)

The mangroves were once nurseries for the mud crab, barramundi and prawn fisheries, but now consist mainly of dead trees and dusty earth.
The few live seedlings coming through are exposed, and vulnerable to damage from the fallen dead trees.
"Through the mangroves you get a lot of bush tucker, mud mussels and shells, and they're all just dead. It just makes me feel sad," Ms Evans said.
Scientists from Queensland and Northern Territory universities said one contributing factor was a temporary drop in sea levels, caused by a change in the trade winds, which left the forests unusually high and dry.
But they said another factor in the dieback along 1,000 kilometres of coastline was climate change and a sharp increase in the sea temperature.
Dead shellfish now line the coastline, where mangroves used to thrive. (ABC News: Jane Bardon)

On par with Great Barrier Reef bleaching
"We can't see any other driver of the dieback other than the extreme climatic envelope has shifted," Charles Darwin University professor Lindsay Hutley said.
Dr Hutley said the extent and duration of the dieback was on a par with the severity of Great Barrier Reef bleaching.
"It's the canary on the coastline; it's quite significant, probably globally significant," he said.
Madeline Goddard and Lindsay Hutley are seeing mangroves move inland. (ABC News: Jane Bardon)

Along with colleague Madeline Goddard, Dr Hutley has been researching other impacts of climate change on mangroves.
They've found mangroves have been adapting to climate change and sea level changes by moving inland.
"In parts of the Top End we are experiencing some of the highest sea level rises in the world," Ms Goddard said.
"If we give mangroves space, the whole forest can move landward, until they hit manmade barriers, and then they are at risk of drowning.
"That they are shifting, to this large degree, because of these climate change influences, is a warning to us."
Polar icecap melting underestimated
The CSIRO has mapped the average sea level rise of the Top End at between six and 13 millimetres a year — two to three times the rate off southern Australia and the global average.
Professor Stephen Garnett has said the Top End may have a sea level rise of a metre by the end of the century. (ABC News: Jane Bardon)
"That is partly because north of here we've got the Arafura Sea, which lies on top of the Continental Shelf, and so it's very shallow and so it warms up very quickly," Stephen Garnett from the Charles Darwin University Research Institute for the Environment said.
"So, we're looking at a metre rise by the end of the century, and we've already had a fifth of that," Professor Garnett said.
CSIRO Sea Level and Coastal Extremes senior researcher Kathy McInnes said even if the Global Paris emissions reduction targets were met, that would not be enough to stop this rate of sea level rise.
Dr McInnes said the impacts of polar icecap melting on sea level rise had also been underestimated.
Northern Australia's mangroves could be under threat from rising sea levels. (ABC News: Nick Hose)
She warned that would leave the Top End vulnerable to more impacts like mangrove dieback.
"We can expect greater frequency at which extreme events can occur, and this can lead to cascading impacts on society and ecosystems like the massive dieback of mangroves," she said.
"The compounding effect of that can be felt years down the track because of the flow on effect into our fishing industry, when stocks of both prawns and fish species drop."

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If Warming Exceeds 2°C, Antarctica’s Melting Ice Sheets Could Raise Seas 20 Metres In Coming Centuries

The Conversation -  | 

During the Pliocene, up to one third of Antarctica’s ice sheet melted, causing sea-level rise of 20 metres. www.shutterstock.com, CC BY-ND
We know that our planet has experienced warmer periods in the past, during the Pliocene geological epoch around three million years ago.
Our research, published today, shows that up to one third of Antarctica’s ice sheet melted during this period, causing sea levels to rise by as much as 20 metres above present levels in coming centuries.
We were able to measure past changes in sea level by drilling cores at a site in New Zealand, known as the Whanganui Basin, which contains shallow marine sediments of arguably the highest resolution in the world.
Using a new method we developed to predict the water level from the size of sand particle moved by waves, we constructed a record of global sea-level change with significantly more precision than previously possible.
The Pliocene was the last time atmospheric carbon dioxide concentrations were above 400 parts per million and Earth’s temperature was 2°C warmer than pre-industrial times. We show that warming of more than 2°C could set off widespread melting in Antarctica once again and our planet could be hurtling back to the future, towards a climate that existed three million years ago.

 Overshooting the Paris climate target
Last week we saw unprecedented global protests under the banner of Greta Thunberg’s #FridaysForFuture climate strikes, as the urgency of keeping global warming below the Paris Agreement target of 2°C hit home. Thunberg captured collective frustration when she chastised the United Nations for not acting earlier on the scientific evidence. Her plea resonated as she reminded us that:
With today’s emissions levels, that remaining CO₂ budget [1.5°C] will be entirely gone in less than eight and a half years.
At the current rate of global emissions we may be back in the Pliocene by 2030 and we will have exceeded the 2°C Paris target. One of the most critical questions facing humanity is how much and how fast global sea levels will rise.
According to the recent special report on the world’s oceans and cryosphere by the Intergovernmental Panel on Climate Change (IPCC), glaciers and polar ice sheets continue to lose mass at an accelerating rate, but the contribution of polar ice sheets, in particular the Antarctic ice sheet, to future sea level rise remains difficult to constrain.
If we continue to follow our current emissions trajectory, the median (66% probability) global sea level reached by the end of the century will be 1.2 metres higher than now, with two metres a plausible upper limit (5% probability). But of course climate change doesn’t magically stop after the year 2100.

 Drilling back to the future
To better predict what we are committing the world’s future coastlines to we need to understand polar ice sheet sensitivity. If we want to know how much the oceans will rise at 400ppm CO₂, the Pliocene epoch is a good comparison.
Back in 2015, we drilled cores of sediment deposited during the Pliocene, preserved beneath the rugged hill country at the Whanganui Basin. One of us (Timothy Naish) has worked in this area for almost 30 years and identified more than 50 fluctuations in global sea level during the last 3.5 million years of Earth’s history. Global sea levels had gone up and down in response to natural climate cycles, known as Milankovitch cycles, which are caused by long-term changes in Earths solar orbit every 20,000, 40,000 and 100,000 years. These changes in turn cause polar ice sheets to grow or melt.
While sea levels were thought to have fluctuated by several tens of metres, up until now efforts to reconstruct the precise amplitude had been thwarted by difficulties due to Earth deformation processes and the incomplete nature of many of the cycles.
Our research used a well-established theoretical relationship between the size of the particles transported by waves on the continental shelf and the depth to the seabed. We then applied this method to 800 metres of drill core and outcrop, representing continuous sediment sequences that span a time period from 2.5 to 3.3 million years ago.
We show that during the Pliocene, global sea levels regularly fluctuated between five to 25 metres. We accounted for local tectonic land movements and regional sea-level changes caused by gravitational and crustal changes to determine the sea-level estimates, known as the PlioSeaNZ sea-level record. This provides an approximation of changes in global mean sea level.

Antarctica’s contribution to sea-level rise
Our study also shows that most of the sea-level rise during the Pliocene came from Antarctica’s ice sheets. During the warm Pliocene, the geography of Earth’s continents and oceans and the size of polar ice sheets were similar to today, with only a small ice sheet on Greenland during the warmest period. The melting of the Greenland ice sheet would have contributed at most five metres to the maximum 25 metres of global sea-level rise recorded at Whanganui Basin.
Of critical concern is that over 90% of the heat from global warming to date has gone into the ocean. Much of it has gone into the Southern Ocean, which bathes the margins of Antarctica’s ice sheet.
Already, we are observing warm circumpolar deep water upwelling and entering ice shelf cavities in several sites around Antarctica today. Along the Amundsen Sea coast of West Antarctica, where the ocean has been heating the most, the ice sheet is thinning and retreating the fastest. One third of Antarctica’s ice sheet — the equivalent to up to 20 metres of sea-level rise — is grounded below sea level and vulnerable to widespread collapse from ocean heating.
Our study has important implications for the stability and sensitivity of the Antarctic ice sheet and its potential to contribute to future sea levels. It supports the concept that a tipping point in the Antarctic ice sheet may be crossed if global temperatures are allowed to rise by more than 2℃. This could result in large parts of the ice sheet being committed to melt-down over the coming centuries, reshaping shorelines around the world.

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From Kerri-Anne To The Masked Stinger: How Australia's Media Covered Extinction Rebellion

The Guardian - 

The Daily Mail promised nudity, the Daily Telegraph tried to generate buzz while the West Australian ran a blank front page
Studio 10’s Kerri-Anne Kennerley suggested Extinction Rebellion protesters be used as speed humps or be locked up in jail and starved. Photograph: Joel Carrett/AAP 
Daily Telegraph reporter Mitchell Van Homrigh got dressed up in a bee costume to go “undercover” with Extinction Rebellion but his stunt wasn’t even the most foolish response to the mass protests we saw this week.
After making all the bee puns he could think of, Van Homrigh admitted he found the protesters “passionate and kind and helpful to this blind little bee”. But he finished by reverting to the Joe Hildebrand school of argument about how little the protest would help their cause.
“Would these people be better off directing their passions towards developing programs and policy that enact their vision?” he wondered as he removed his bee head.
Hildebrand had earlier declared in his weekly news.com.au column that global action for climate change was a waste of time unless the protesters had a solution, as “passion on its own achieves nothing without a practical plan to back it up”.
“Romeo and Juliet were passionate and look what happened to them,” the Studio 10 co-host wrote, before conceding that marching was at least better than doing drugs.
But it was Hildebrand’s occasional co-host on Studio 10, Kerri-Anne Kennerley, who stole the headlines with the most offensive response to the protests.
Kennerley suggested that protesters be used as speed bumps. Or better still locked up in jail and starved: “Put ’em in jail, forget to feed them,” she said.
“Personally, I would leave them all superglued to wherever they do it,” Kennerley said when the panel discussed the disruption to the cities the protesters were causing. “The guy hanging from the Story Bridge. Why send emergency services? Leave him there until he gets himself out. No emergency services should help them, nobody should do anything and you just put little witches’ hats around them or use them as a speed bump.”
Channel 10, which this week narrowly missed censure for an earlier ill-advised comment by Kennerley, later insisted the veteran TV presenter was only joking.
“This morning on Studio 10 Kerri-Anne Kennerley made comments regarding climate protesters that were said in jest,” a spokesman said. “Before the show concluded, Sarah Harris reiterated the tone of her remarks, affirming that Kerri-Anne wasn’t inciting violence.
“Kerri-Anne confirmed that she was indeed speaking in hyperbole and her words were clearly a joke. There was no intent to cause offence. Over the past few days, Studio 10 has extensively addressed a range of opinions on this subject.”
The Australian’s media editor, Leo Shanahan, saw nothing amiss with KAK’s call, describing her rant as “sage advice”.
“Kerri-Anne Kennerley has some sage advice to Extinction Rebellion protesters: just stay on the road”, the Oz said.
It wasn’t just Ten that was all class this week. The media tripped over each other to put the worst light on the protesters who were using civil disobedience to get the attention of governments. Seven breakfast host Samantha Armytage said the protesters were annoying people to get on TV.
“So you deliberately want to annoy people, so you appear on national television,” Armytage said. “What is your message? What are you trying to do?”
Nine’s A Current Affair took the theme of the inconvenienced punter to the extreme, finding a woman stuck in traffic who was on her way to clear out her late mother’s nursing home. Her mother had died on Sunday and now she had been blocked by the protest.
“Fuck the environment,” the distressed daughter said. “People are more important.
“They think [protesting] is so important but what is important is the everyday, good Australian people just trying to go about their everyday lives. It’s not fair.”
The Daily Telegraph blogger Tim Blair kept score of the arrests in each city, as if it were a sporting competition. His best line in National Climate Comp: Sydney Going for Gold was suggesting that the protesters must be on “electric lettuce”, also known as marijuana.
The West Australian editor, Anthony De Ceglie, thought he had an even better gimmick, running a large blank space on his front page.
“The climate change ‘rebellion’ plans to bring its protests to the doors of the West Australian today,” he editorialised. “This is a democracy. And we support free speech and peaceful demonstration. In that spirit, here’s a blank front page for your placards. Use it wisely.”
But the last word should go to the Daily Mail, which got way too excited about the possibility of nudity, with activists planning to “get their gear off”.
“A NAKED parade and traffic stopping rave: how Extinction Rebellion plan to bring Australia to a standstill during week of mayhem over climate change,” the headline said on Tuesday.

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