Ocean heat melting Totten Glacier from below …
Media Release, first published December 17
Australian research has confirmed that warm water flowing through a deep channel under East Antarctica's largest glacier is driving rapid melting.
The research, to be published today in Science Advances, sheds new light on the vulnerability of the East Antarctic ice sheet to ocean heat, which is one of the biggest unknown factors for global sea level rise projections.
In 2014-15, researchers aboard the Australian research vessel Aurora Australis gathered the first oceanographic data from the calving front of the Totten Glacier, when a long crack opened up in sea ice that is normally impenetrable to ships.
Lead author, Dr Steve Rintoul, the Interim Director of CSIRO's Climate Science Centre and ACE CRC Project Leader, said that no oceanographic measurements from the Totten Ice Shelf had been available to test the hypothesis that warm ocean waters were driving melting of the ice shelf from below.
"We knew from satellite data that the Totten has been thinning faster than other glaciers in East Antarctica, but we didn't know why," said Dr Rintoul.
"A lucky break in the sea ice allowed us to get the ship in there and take the first measurements of the water column and sea floor in this area.
"We discovered a large channel in front of the western side of the Totten Glacier which is around 10 kilometres wide and up to a kilometre deep.
"We found that warm ocean water is reaching the ice shelf through this channel, with temperatures high enough to drive rapid melt of the underside of the ice shelf.
"This is important because the ice shelf acts as a sort of plug that restricts the flow of ice from Antarctica to the ocean."
Dr Rintoul said the results also showed that, on an area-averaged basis, Totten has the highest basal melt rate among Eastern Antarctic ice shelves larger than 1000 km2.
"If warm ocean waters drive more rapid melt of the Totten and other ice shelves around the edge of Antarctica, more glacial ice can flow into the ocean, raising sea level," said Dr Rintoul.
"The Totten is the largest glacier in East Antarctica, and it contains enough ice to raise global sea levels by about 3.5 metres if it all melted, so it is important to know how it will behave in the future."
The publication of the research comes as scientists attempt a second expedition to the Totten Glacier front, where they hope to profile areas of ocean that were inaccessible during their 2014-15 expedition, due to sea ice.
A team of around 30 scientists, technicians and PhD students from CSIRO, the Antarctic Climate & Ecosystems CRC (ACE CRC), the University of Tasmania, and the Australian Antarctic Division left Hobart on December 8, aiming to arrive at the glacier in late December.
"Now that we know warm water is reaching the underside of the glacier, we want to use this voyage to learn more about the pathways that bring this warm water up from the deep ocean," said Dr Rintoul.
"Understanding the physical processes delivering heat to the ice shelf will help us assess the vulnerability of the East Antarctic Ice Sheet to future changes in the Southern Ocean."
• The Conversation: Climate change played a role in Australia's hottest October and Tasmania's big dry in 2015 Climate change made some of Australia's 2015 extreme weather events more likely, according to research published today in the Bulletin of the American Meteorological Society. As part of an annual review of global weather extremes, these studies focused on October 2015, which was the hottest on record for that month across Australia. It was also the hottest by the biggest margin for any month. October 2015 was also the driest for that month on record in Tasmania, which contributed to the state's dry spring and summer, and its bad fire season …
phill Parsons
The results from the Totten Glacier are unsurprising with almost all glaciers whose tongues interact with the ocean in retreat. Those not doing so are the exceptions where the water remains cold enough due to circulation patterns that are unlikely to last. The same gors for glaciers on the land and their interaction with the air and soot deposits.
The surprise will be concerted global action to limit the degree of warming. Our current government will be a leader in delay and deferment. We have to change the trajectory by rapidly reducing Carbon emissions.
Like the glaciers there are a few who don't follow. Vocal opponents to action will be swept aside by events because the evidence is inescapable.
Kim Peart
Re: 20 ~ Low lying suburbs in Tasmania, including Lauderdale and Kingston Beach, will be some of the first to face the insurance vacuum.
When living in Mountain Creek on Queensland's Sunshine Coast, life gained a little too much excitement a few years ago, when heavy rain turned our street into a river. If there had been a king tide and or a storm at sea, we would have been flooded and many homes in this heavily populated area would have been lost.
Much of the Sunshine Coast has been developed on the old flood plain, which by itself means flood events from time to time. Add the predictions of climate change to the flood plain, with heavier rain, sea level rise and fiercer storms, and there are a great many coastal locations that are now at risk from both Nature and insurance cover.
When Nature hits, fuelled by the sum of our carbon emissions, the event is likely to be sudden and decisive. Once the sea starts flowing through a flood plain, new waterways will run where suburbs once were.
The doom will rise, year by year, as the sea level rises, and sunny day floods will become quite common on Australia's vast coast.
Will we get wise as a nation and start moving flood plain suburbs to higher ground?
Is Lauderdale on the flood plain about to be moved to higher ground?
Keith Antonysen
Russell, you can add the Marshall Islands to the list.
They have sunny day floods in Florida where suburban streets are flooded when there are king tides. Republicans will not admit that is due to climate change. As a result of the flooding, Insurance Companies are unwilling to provide a cover in some areas.
Australia should have a good look at hydrogen. Saltwater can be made into hydrogen by electrolysis in remote areas where we have huge tides and piped to our cities, or were needed and as a bonus it converts back to electricity and we get pure clean water. Hydrogen can be the guarantee for base load and combined with bioemthane Australia could be totally free from coal and oil. There is only a 25% recovery from the original generation but with low generation costs, pure water and no transmission losses this is possibly the way to go.
#16 I could surprise you- but won't.
Trevor Cowle at No 12, if you had been keeping yourself informed about what's happening in Antarctica you would be aware that glaciers of Western Anatarica are in a poor state of health …Pine Island, Thwaites, Haynes, Smith and Pope are voiding huge amounts of ice and are seen to be unstable.
An area of around 4,009 square kilometres is preparing to detach from the Larson C ice sheet.
The state of Antarctica has been established through observation and data; those who make puerile or skeptical comments only rely on opinion.
Phillip – 13 – You have to dig a bit to find the treasures – http://oldtt.pixelkey.biz/index.php?/weblog/article/in-tasmania-some-people-never-change-/
Re: 12 ~ For a house, a fire can be lurking in the future, which is why we take out house insurance, so we can build another house.
For us, extinction can be lurking in the future, which is why we can have good reason to invest in survival insurance, so we will maximise our chances for survival, and be able to enjoy prosperity and being creative.
Have we adequately invested in survival insurance?
If not, what should be done about it?
PHilip Lowe
TGC No12.Why don't you be brave and use your full name.If the TG stands for trans gender then I think that I know who you are.
#10 "In the meantime,something is lurking in the future." Go on, be brave, tell us what it is -and when will it happen? If it's "lurking" someone must know about it.
Re: 10 ~ Coal diggers and oil drillers and gas pumpers are not the problem.
The strife we are now sucked into is a consequence of too many people running wild on the boon of coal digging and oil drilling and gas pumping, as if there was no tomorrow.
Considering how the carbon problem was common knowledge in the early 1900s when written about in local newspapers, and was described in a White House science report in 1965, the truth has been out there for a very long time.
The solution to progress without restriction was energy transition, from fossil fuel to solar power, when this became possible in the 1970s with solar power stations in space.
Some strange reticence at the option simple empowered fossil fuel to deliver a carbon crisis, which is now speeding into our future.
The solution to the carbon crisis will be the same as was the prevention, when a critical number of people wake up and see that only with energy transition can we win back a safe Earth, which must now include space based solar power for the clean green energy to extract excess carbon from the air.
Without carbon extraction, we will be well and truly buggered.
Sea levels will rise,and so will the price of ocean front housing.
Nothing is forever.Joni Mitchell said it,"don't it only go to show,
You don't know what you've got till it's gone,take paradise,put up a parking lot".Genesis was /is an environmental disaster.
Here in the UK,the Godbotherers worship the buildings,Cathedrals etc.Bricks and mortar religions.The desecration of Planet Earths resources stem from religion based demands.Religion poisons everything.When was the last time you heard of a foreign aid budget including a condition re population control,family planning,contraception?
Go ahead,mine your coal,bugger the Barrier Reef,do a Torrey Canyon or an Exxon Valdiz.Make shitloads of money for your budgets so that you can over beaurocratise your system.
In the meantime,something is lurking in the future.
john hayward
Thank you, #2, TGC, for your demonstration of projection, which in this case is the imposition of Liberal Party fixations with personal aggrandisement on to oceanographers and other scientists.
Re: 3 ~ The full paper can be read here ~
https://www.researchgate.net/publication/282535729_Long-term_response_of_oceans_to_CO2_removal_from_the_atmosphere
The conclusion states ~
"Independent of the question whether a return to pre-industrial conditions would be possible, it is reasonable to assume that marine organisms would experience further stress instead of relief if they were forced to re-adapt to pre-industrial conditions. Thus, our findings contribute to the growing body of evidence supporting the view that immediate and ambitious action to reduce CO2 emissions is the most reliable strategy for avoiding dangerous climate change, ocean acidification, and large-scale threats to marine ecosystems."
It is a fact that the rise of CO2 in the air and sea has changed plant biology and forced evolutionary change, so to draw down CO2 will again impact plants and animals.
This paper leaves out the warning from James Hansen and others that with CO2 above 350 ppm in the air, conditions are in place that will lead to a runaway greenhouse effect.
Reducing carbon emissions will not stop the rise in CO2 in the air going beyond 500 ppm and probably 600 ppm, driving up temperature rise and dangerous Earth changes, including with heat levels, climate events, plant biology and ocean acidity.
I noticed that James Hansen is not referred to in this article.
The only way to draw down the Earth changes that lead to a runaway greenhouse effect, is to draw down the level of CO2 in the air below 350 ppm (now beyond 400 and rising at 3 ppm per annum).
Citizens will have no cause for conviction if they see that the level of CO2 in the air keeps going up and the Earth's temperature rises.
The most immediate threat we may face is environmental crisis that tumbles into global conflict, which could all too easily slide into nuclear madness.
The Syrian civil war is likely a result of climate change, because of a prolonged drought.
If the Syrian civil war, like Spanish civil war, is a step to a global conflict, then we can learn from history and act, or get swollowed by events.
With Syria, the United States has been swollowed by events and the stage has swayed to favour something that looks all too much like a repeat of the Spanish Civil War.
If round one of that war was Russian interferance in the US presidential election, then history may judge that as a Russian victory.
China has pursued occupation of the South China Sea, leaving triggers for global conflict in Europe and Asia.
Exactly how climate change is dealt with now, will determine peace on Earth and human survival.
Re: 3 ~ This article is locked, unless money is forked out for access.
Climate change is driving stronger winds in Antarctica, which on the one hand is helping to keep Antarctica cool.
On the other hand, stronger winds blow the snow away, leaving darker exposed ice, which absorbs more solar energy, which can lead to the ice melting, lakes forming, and the warmer water, as water is always warmer than ice, draining into the ice sheet.
This is happening now ~
https://www.newscientist.com/article/2114844-mystery-antarctic-circle-means-ice-is-melting-from-surface-down/
So with stronger winds leading to the melting of ice on the surface, and warmer water working its way beneath, leads to melting Antarctic ice delivering more sea level rise.
Eastern Antarctica had been considered to be the stable part of the continent, found to be wrong in the fairly recent past; and now confirmed by further research. The huge glaciers of Western Antarctica have been breaking down; whether caused by anthropogenic climate change or natural varibility, the result is the same.
https://www.washingtonpost.com/news/energy-environment/wp/2016/12/16/warm-ocean-water-is-slamming-into-and-melting-the-biggest-glacier-in-east-antarctica/?utm_term=.7eae629066a7
The apparent cosy relationship between Putin and Trump/Tillerson:
https://medium.com/@AlexSteffen/trump-putin-and-the-pipelines-to-nowhere-742d745ce8fd#.zhuj92b7k
ABC report of the story ~
http://www.abc.net.au/news/2016-12-17/search-for-source-of-warm-water-melting-totten-glacier/8129202
Jon Sumby
http://www.nature.com/nclimate/journal/v5/n12/full/nclimate2729.html
It is vital to the continuing employment of scientists that the possibility the Antarctic ice might all melt and raise the sea level so much that the China development in the Pacific goes underwater
(take a breath) is investigated for the next 100 or so years at least.
How many canaries need to keel over in the coal mine of dangerous Earth changes, before the dots are connected from the looming carbon apocalypse to a working solution that wins back a safe Earth?
If the root cause is accepted, that CO2 above 350 ppm in the air trips the wires, then this was passed in the 1980s.
Greenhouse gases are now exploding into the air, with the Earth kicking in to warm up the air and sea, to melt ice, to drive up sea level rise to who knows how much.
I read that the last time CO2 in the air was at 400 ppm, the planet's temperature was 3C up and the ocean was 5 metres higher.
With CO2 in the air rising at 3 ppm per annum and set to accelerate, simple maths says we get 500 ppm within a couple of decades, with little chance of braking before sailing past 600 ppm.
The feedbacks are kicking in now, so even if humans vanished from the face of the Earth today, the carbon forces in play will carry on.
If we love the Earth, if we love life, if we want a future for our children on a safe Earth, then the prime game in town is carbon extraction, which can be done, but requires a heap of energy.
The only climate question that counts is, where will we get the level of clean green energy from to extract excess carbon from the air, to win back a safe Earth?
All other considerations are details that will fall into place later, and inspire participation, when the main challenge is being dealt with.
Until that happens, people will feel no hope as they say atmospheric CO2 rising every year, along the Earth's temperature and sea level.
Sadly, planet heat and sea lever will go up quite a lot, before they can be pulled back.
The longer the real action is delayed, the higher planet temperature and sea level will rise.
What is the plan to win back a safe Earth?