Antarctica Loses Three Trillion Tonnes Of Ice In 25 Years

BBC - Jonathan Amos | Victoria Gill

Artwork: European satellites in particular have an unbroken record going back to 1992 ESA

Antarctica is shedding ice at an accelerating rate.

Satellites monitoring the state of the White Continent indicate some 200 billion tonnes a year are now being lost to the ocean as a result of melting.
This is pushing up global sea levels by 0.6mm annually - a three-fold increase since 2012 when the last such assessment was undertaken.
Scientists report the new numbers in the journal Nature.
Governments will need to take account of the information and its accelerating trend as they plan future defences to protect low-lying coastal communities.
The researchers say the losses are occurring predominantly in the West of the continent, where warm waters are getting under and melting the fronts of glaciers that terminate in the ocean.
"We can't say when it started - we didn't collect measurements in the sea back then," explained Prof Andrew Shepherd, who leads the Ice sheet Mass Balance Inter-comparison Exercise (Imbie).
"But what we can say is that it's too warm for Antarctica today. It's about half a degree Celsius warmer than the continent can withstand and it's melting about five metres of ice from its base each year, and that's what's triggering the sea-level contribution that we're seeing," he told BBC News.
Space agencies have been flying satellites over Antarctica since the early 1990s. Europe, in particular, has an unbroken observation record going back to 1992.
These spacecraft can tell how much ice is present by measuring changes in the height of the ice sheet and the speed at which it moves towards the sea. Specific missions also have the ability to weigh the ice sheet by sensing changes in the pull of gravity as they pass overhead.
Imbie's job has been to condense all this information into a single narrative that best describes what is happening on the White Continent.
Glaciologists usually talk of three distinct regions because they behave slightly differently from each other. In West Antarctica, which is dominated by those marine-terminating glaciers, the assessed losses have climbed from 53 billion to 159 billion tonnes per year over the full period from 1992 to 2017.
On the Antarctic Peninsula, the finger of land that points up to South America, the losses have risen from seven billion to 33 billion tonnes annually. This is largely, say scientists, because the floating ice platforms sitting in front of some glaciers have collapsed, allowing the ice behind to flow faster.
East Antarctica, the greater part of the continent, is the only region to have shown some growth. Much of this region essentially sits out of the ocean and collects its snows over time and is not subject to the same melting forces seen elsewhere. But the gains are likely quite small, running at about five billion tonnes per year.
And the Imbie team stresses that the growth cannot counterbalance what is happening in the West and on the Peninsula. Indeed, it is probable that an unusually big dump of snow in the East just before the last assessment in 2012 made Antarctica as a whole look less negative than the reality.
Globally, sea levels are rising by about 3mm a year. This figure is driven by several factors, including the expansion of the oceans as they warm. But what is clear from the latest Imbie assessment is that Antarctica is becoming a significant player.
"A three-fold increase now puts Antarctica in the frame as one of the largest contributors to sea-level rise," said Prof Shepherd, who is affiliated to Leeds University, UK.
"The last time we looked at the polar ice sheets, Greenland was the dominant contributor. That's no longer the case."
In total, Antarctica has shed some 2.7 trillion tonnes of ice since 1992, corresponding to an increase in global sea level of more than 7.5mm.
The latest edition of the journal Nature has a number of studies looking at the state of the continent and how it might change in a warming world.
One of these papers, led by US and German scientists, examines the possible reaction of the bedrock as the great mass of ice above it thins. It should lift up - something scientists call isostatic readjustment.
New evidence suggests where this process has occurred in the past, it can actually constrain ice losses - as the land rises, it snags on the floating fronts of marine-terminating glaciers.
"It's like applying the brakes on a bike," said Dr Pippa Whitehouse from Durham University. "Friction on the bottom of the ice, which was floating but has now grounded again, slows everything and changes the whole dynamic upstream. We do think the rebound (in the future) will be fast, but not fast enough to stop the retreat we've kicked off with today's warming.
"Ocean warming is going to make the ice too thin for this process to help."
In Imbie's last assessment, the contribution of Antarctica to global sea-levels was considered to be tracking at the lower end of the projections that computer simulations had made of the possible height of the oceans at the end of the century. The new assessment sees the contribution track the upper end of these projections.
"At the moment, we have projections going through to 2100, which is sort of on a lifetime of what we can envisage, and actually the sea-level rise we will see is 50/60cm," said Dr Whitehouse. "And that is not only going to impact people who live close to the coast, but actually when we have storms - the repeat time of major storms and flooding events is going to be exacerbated," she told BBC News.

Links

• Antarctic Ice Melting Faster Than Ever, Studies Show
• The rate of Antarctic melting has nearly tripled in the past five years
• Global warming is melting Antarctic ice from below
• Melting ice sheets are hastening sea level rise, satellite data confirms
• Antarctic ice sheets face catastrophic collapse without deep emissions cuts
• Vast Antarctic ice shelf a few years from disintegration, says Nasa
• Antarctic ice shelves are melting dramatically, study finds
• Warmer seas could cause faster melting of Antarctic ice leading to rising sea levels, says study
• Choosing the future of Antarctica
• Mission launches to weigh Earth's water
• Biggest ever Antarctic field campaign
• Giant iceberg splits from Antarctic

National Energy Guarantee 'Clumsy, Inefficient', Says VEPC's Mountain

Fairfax - Peter Hannam

The Turnbull government's proposed revamp of Australia's electricity sector has many unresolved issues just two months before states and territories are supposed to sign off on the plan, the head of the new Victorian Energy Policy Centre said.
Bruce Mountain, who will launch the new centre in Melbourne on Wednesday, said the National Energy Guarantee (NEG) as designed would not reduce coal generation and would "only slightly increase renewable capacity".
"It's clumsy and inefficient," and deliberately set up to hide a market price for emissions, Dr Mountain told Fairfax Media. The government's own forecasts say "it will move nothing in a meaningful sense".

Bayswater power station in the Hunter Valley: what role coal? Photo: Nick Moir

Among Dr Mountain's concerns - to be detailed in a speech at the launch - was the lack of a penalty for non-compliance, undermining the policy's credibility.
While retailers would be obligated to reduce the emissions intensity of the electricity they purchase, the reliance on a registry rather than a market to settle shortfalls would also hinder transparency. One consequence would be to hobble the development of financial instruments, potentially raising costs.
The overall approach was "without precedent [and is] projected to make effectively no difference to greenhouse gas emissions relative to business as usual", Dr Mountain will say in his speech.
By contrast, Australia had a readymade market for the Renewable Energy Target (RET), which would be much more effective than the NEG, he said.
The creation of the new policy centre - based at Victoria University and mostly funded by the Andrews Victorian government - is likely to increase scrutiny on the NEG in the final months of its development.
Josh Frydenburg, the federal environment and energy minister, wants states and territories to agree on the plan by August 10.
The scheme aims to reduce power prices while improving security of the grid as the share of renewable energy sources increase. It also intends to ensure the electricity sector - sources of about one-third of Australia's carbon emissions - meets Australia's Paris climate commitment of cutting 2005-level emissions 26-28 per cent by 2030.

Energy crunch time: Federal environment and energy minister Josh Frydenberg will be pressing for approval for the National Energy Guarantee in August. Photo: Janie Barrett

“There is an unprecedented cross section of support for the NEG," Mr Frydenberg said.
“The independent Energy Security Board’s (ESB) modelling found that the guarantee would add over 3200 megawatts of additional renewable capacity compared to business as usual and would result in lower prices," he said, adding that household power bill would fall by an average of $400 by 2020.

'Short timeframe'
Dr Mountain said the requirement of the electricity sector to meet only an average emissions reduction goal "would impose costs - probably large - elsewhere in the economy in order to deliver the Paris commitment".
The Australian Energy Council, which represents major generators, said the NEG had made major design advances since its conception late last year with the Energy Security Board set up to drive it.
Still, "the [board] are working to a remarkably short timeframe to deliver a largely completed reform", a council spokeswoman said.
Among the council's concerns, as detailed in its submission, the body would prefer only the high-level structure and legislation be set up now. The more complex details would then be set up within the National Electricity Rules over time.
"Whilst our cautious approach is preferred where feasible, we have to acknowledge that the ESB has a difficult juggling act to retain support across so many parties, and are therefore under pressure to deliver it in considerable detail before the next COAG meeting," the spokeswoman said.
Another concern for Dr Mountain was the current NEG design - unlike the RET - could provide a windfall for old hydro stations owned by Snowy Hydro and Hydro Tasmania. While the current low emissions ambition of the Turnbull government meant the transfers would be minimal, that would change if a future Labor government took over and significantly increased the electricity sector's emissions-reduction load.

High costs
Tackling the NEG issues will be only part of the new policy centre's priorities.
Tackling the high costs of electricity in general will be another, with Australian states now enduring the high power charges before tax in the world, according to data analysed by Dr Mountain.
The retailers charges amounted to about $423 of the almost $1400 typical residential bill in Victoria as of May 2017, Dr Mountain's data showed. That compared with $73 for state and federal environmental schemes, $415 for networks and $263 for the actual wholesale generation charge.

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Typical retail electricity prices in 2017 at market rates

Source: Mountain (2017)

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Of those retailers' charges, Victoria was the highest in Australia, followed by NSW, and considerably higher than other nations. The European Union's average retailer charge of about 2 Australian cents per kilowatt-hour compared was a fraction of Victoria's 12 cent charge, and more than 8 cents in NSW.

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Retailers' charge for typical residential electricity user

Source: Mountain (2017)

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Links

• National Energy Guarantee – Draft Design Consultation Paper (pdf)
• Power sector emissions dip stalls, while transport revs up
• New policy hub to tackle 'vested interests' in energy sector
• $500,000 wind farm experts provided no advice in two years
• Queensland budget dreams of electric super highway
• Tomago Aluminium warns of 'energy crisis' as power supply falters
• Energy bosses say power companies need to work together, or else
• NSW launches strategy to increase renewable power in the state
• Too much of a good thing: Solar power surge is flooding the grid
• Limiting global warming to 2 degrees now 'aspirational': scientists
• Former EnergyAustralia exec says electricity retailers are unethical

Antarctic Ice Melting Faster Than Ever, Studies Show

The Guardian - Matthew Taylor

Rate of melt has accelerated threefold in last five years and could contribute 25cm to sea-level rises without urgent action

Scientists warns time is running out to save the Antarctic and its unique ecosystem, with potentially dire consequences for the world. Photograph: Daniel Beltrá/Greenpeace 

Ice in the Antarctic is melting at a record-breaking rate and the subsequent sea rises could have catastrophic consequences for cities around the world, according to two new studies.
A report led by scientists in the UK and US found the rate of melting from the Antarctic ice sheet has accelerated threefold in the last five years and is now vanishing faster than at any previously recorded time.
A separate study warns that unless urgent action is taken in the next decade the melting ice could contribute more than 25cm to a total global sea level rise of more than a metre by 2070. This could lead eventually to the collapse of the entire west Antarctic ice sheet, and around 3.5m of sea-level rise.
Prof Andrew Shepherd, a lead author of the study on accelerating ice loss, said: “We have long suspected that changes in Earth’s climate will affect the polar ice sheets. Thanks to our satellites our space agencies have launched, we can now track their ice losses and global sea level contribution with confidence.”
He said the rate of melting was “surprising.”
“This has to be a cause for concern for the governments we trust to protect our coastal cities and communities,” Shepherd added.
The study, published in Nature, involved 84 scientists from 44 international organisations and claims to be the most comprehensive account of the Antarctic ice sheet to date. It shows that before 2012, the Antarctic lost ice at a steady rate of 76bn tonnes per year - a 0.2mm per year contribution to sea-level rise. However since then there has been a sharp increase, resulting in the loss of 219bn tonnes of ice per year - a 0.6mm per year sea-level contribution.
The second study, also published in Nature, warns that time is running out to save the Antarctic and its unique ecosystem - with potentially dire consequences for the world.
The scientists assessed the probable state of Antarctica in 2070 under two scenarios. The first in which urgent action on greenhouse gas emissions and environmental protection is taken in the next few years, the second if emissions continue to rise unabated and the Antarctic is exploited for its natural resources.
The scenario which plays out largely depends on choices made over the next decade, on both climate-change and on environmental regulation, they conclude.
Co-author Profe Martin Siegert, from the Grantham Institute, said: “Some of the changes Antarctica will face are already irreversible, such as the loss of some ice shelves, but there is a lot we can prevent or reverse.
“To avoid the worst impacts, we will need strong international cooperation and effective regulation backed by rigorous science. This will rely on governments recognising that Antarctica is intimately coupled to the rest of the Earth system, and damage there will cause problems everywhere.”
As well as being a major cause of sea-level rise, scientists say the oceans around Antarctica are a key “carbon sink” - absorbing huge amounts of greenhouse gases helping to mitigate the impacts of climate change.
Siegert said: “If the political landscape of a future Antarctica is more concerned with rivalry, and how each country can get the most out of the continent and its oceans, then all protections could be overturned.
“However, if we recognise the importance of Antarctica in the global environment, then there is the potential for international co-operation that uses evidence to enact changes that avoid ‘tipping points’ – boundaries that once crossed, would cause runaway change, such as the collapse of the west Antarctic ice sheet.”

Links

• Antarctica loses three trillion tonnes of ice in 25 years
• The rate of Antarctic melting has nearly tripled in the past five years
• Global warming is melting Antarctic ice from below
• Melting ice sheets are hastening sea level rise, satellite data confirms
• Antarctic ice sheets face catastrophic collapse without deep emissions cuts
• Vast Antarctic ice shelf a few years from disintegration, says Nasa
• Antarctic ice shelves are melting dramatically, study finds
• Warmer seas could cause faster melting of Antarctic ice leading to rising sea levels, says study
• Choosing the future of Antarctica

Power Sector Emissions Dip Stalls, While Transport Revs Up

Fairfax - Peter Hannam

Diesel's carbon emissions have matched petrol for the first time in Australia's transport sector. Photo: Dmitry Panchenko

Cuts in power sector emissions are unlikely to be maintained, while those from the transport sector will continue to climb in the absence of mandatory standards, according to analysis by The Australia Institute.
A separate report by the institute also found Australia's Paris climate goals to be "grossly inadequate".
At the end of March, carbon emissions from electricity generation were down more than 12 per cent compared with mid-2011, with almost the entire drop made up by brown coal-fired power stations.
The closure of Victoria's Hazelwood power plant in March 2017 removed Australia's most carbon-intensive power station.
"From now on ... electricity emissions will fall much more slowly" if not remain flat, Hugh Saddler, an energy analyst and author of the report, said.
"Total energy combustion emissions may well start to increase, as they were doing up to the beginning of 2017 [prior to the Hazelwood closure]."
In the most recent government greenhouse gas data, electricity generation emissions fell 3.1 per cent in 2017, the only sector to record a drop.
Total emissions rose 1.5 per cent last year and are on course to notch a fourth consecutive year of growth. That's a trend at odds with Australia's pledge to cut carbon pollution 26-28 per cent from 2005 levels by 2030,  particularly in the absence of policies to curb fossil-fuel use and looser curbs on land clearing.
In the transport sector – Australia's second-largest source of emissions after power generation – diesel now accounts for more than half the pollution, and is responsible for all its continuing growth, Dr Saddler said in the National Energy Emissions Audit.
Burning diesel typically emits 17 per cent more greenhouse gas than the same amount of petrol, offsetting its higher efficiency.
"Unless the Australian government takes action on emissions standards, we will continue to drive up emissions in the transport sector with one of the least efficient, highest-emission motor vehicle fleets in the world," said Dr Saddler.
"Australia's average fleet efficiency hasn't changed for years and years," he said. Most other wealthy nations had such controls, while emerging giants India and China had them.

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Changes in fossil fuel combustion emissions since 2011

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Fairfax Media approached Josh Frydenberg, environment and energy minister, for comment.
Mr Frydenberg has said previously Australia's per capita reduction targets were among the highest for any nation, that the country would likely easily achieve its climate targets.

Australia's emissions pledge to Paris was less than the country's fair share, The Australia Institute says. Photo: Paul Crock

'Unfair'
In a separate report out Tuesday, however, The Australia Institute took aim at Australia's international commitments, saying the country was not doing its "fair share" to combat climate change.
Applying several approaches used widely to assess nations' contribution, the institute found the government's Paris pledge to be "grossly inadequate".

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How they compare

Average greenhouse gas emissions (including land use change and forestry) per capita 1990-2014

Source: The Australia Institute

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“Whether you assess the fairness of a country’s emissions reduction target by population, economic cost, or a combination, our analysis shows Australia’s reduction target is unambitious, unfair and irresponsible,” Richie Merzian, director of the institute’s Climate & Energy Program, said.
Given Australia's per capita emissions are among the highest in the world, its ambitions should also be high, with a national 2030 reduction target of 45-63 per cent to be fair, the report said.  Labor's target is 45 per cent.
To have a mid-probability of meeting the Paris goal of keeping global warming to well below 2 degrees – compared with about 1 degree to date since pre-industrial times – the world can emit only a further 1040 gigatonnes of carbon-dioxide equivalent, the report noted.
According to Australia's population, the country's fair share of that total would be about 3392 million tonnes – an amount that would be taken up in about six years of current annual emissions.
Getting international co-operation on emissions, though, may be come more difficult in the short term, at least.
US President Donald Trump exited the G7 leaders summit over the weekend in Canada early, avoiding discussions on tackling climate change.  The US signalled a year ago that it would pull out of the Paris accord.
The other six nations – Canada, France, Germany, Italy, Japan and Britain – all pledged to implement the climate agreement, but the US only promised to "work closely with other countries to help them access and use fossil fuels more cleanly and efficiently", according to a report by Inside Climate News.

Links

• Turnbull government's sudden shift raised NEG doubts, Victoria says
• Power sector emissions dip stalls, while transport revs up
• New policy hub to tackle 'vested interests' in energy sector
• $500,000 wind farm experts provided no advice in two years
• Queensland budget dreams of electric super highway
• Tomago Aluminium warns of 'energy crisis' as power supply falters
• Energy bosses say power companies need to work together, or else
• NSW launches strategy to increase renewable power in the state
• Too much of a good thing: Solar power surge is flooding the grid
• Limiting global warming to 2 degrees now 'aspirational': scientists
• Former EnergyAustralia exec says electricity retailers are unethical

Antarctic Ocean Discovery Warns Of Faster Global Warming

Climate Central - Mikayla Mace, Arizona Daily Star

A group of scientists, including one from the University of Arizona, has new findings suggesting Antarctica's Southern Ocean — long known to play an integral role in climate change — may not be absorbing as much pollution as previously thought.
The old belief was the ocean pulled about 13 percent of the world’s carbon dioxide — a greenhouse gas that contributes to climate change — out of the atmosphere, helping put the brakes on rising global temperatures.
To reach their contradictory conclusion, the team used state-of-the-art sensors to collect more data on the Southern Ocean than ever before, including during the perilous winter months that previously made the research difficult if not impossible.
Some oceanographers suspect that less CO2 is being absorbed because the westerlies — the winds that ring the southernmost continent — are tightening like a noose. As these powerful winds get more concentrated, they dig at the water, pushing it out and away.

The crew of the N.B. Palmer used satellite imagery to avoid large fields of sea ice during a mission to deploy and recover floats, which remotely monitor ocean conditions, but sometimes encounters were unavoidable. The research vessel can break through ice three feet thick while traveling at three knots. Credit: Greta Shum/Climate Central

Water from below rises to take its place, dragging up decaying muck made of carbon from deep in the ocean that can then either be released into the atmosphere in the form of CO2 or slow the rate that CO2 is absorbed by the water. Either way, it's not good.
The Southern Ocean is far away, but “for Arizona, this is what matters,” said Joellen Russell, the University of Arizona oceanographer and co-author on the paper revealing these findings. “We don’t see the Southern Ocean, and yet it has reached out the icy hand.”

Joellen Russell, associate professor of geoscience at the University of Arizona, with a climate model of sea surface temperatures. Credit: Kelly Presnell/Arizona Daily Star 

Oceans, rivers, lakes and vegetation can moderate extreme changes in temperature. Southern Arizona has no such buffers, leaving us vulnerable as average global temperatures march upward.
“Everybody asks, ‘Why are you at the UA?’” Russell said about studying the Southern Ocean from the desert at the University of Arizona. She said the research is important to Arizona and the university supports her work.

Making measurements
The Southern Ocean is a formidable place, especially in winter. Winds can howl at nearly 100 mph, churning waves that can surge 80 feet high. The temperature dips below freezing for prolonged periods.
“Very few people who have a sane view of the world go down there in winter,” said Rik Wanninkhof, an oceanographer from the National Oceanic and Atmospheric Administration, and one of the paper’s co-authors.
For this reason, scientists know less about the Southern Ocean than the rest of the world’s oceans. What they do know is mostly limited to surface CO2 levels in the summer, when it’s safer to take measurements by ships with researchers aboard. Shipboard sensors that directly measure CO2 are the accepted scientific standard in these types of studies.
Understanding CO2 levels within the air, land and sea and how it is exchanged between the three is necessary for making more accurate future climate predictions.
To fill the gap in knowledge, Russell and her team have deployed an array of cylindrical tanks, called floats, that collect data on carbon and more in the Southern Ocean year-round. Russell leads the modeling component of this project called Southern Ocean Carbon and Climate Observations and Modeling, or SOCCOM.

Aboard the N.B. Palmer research vessel, marine technician MacKenzie Haberman assisted with the launch of a profiling float in the Southern Ocean, which remotely monitors ocean conditions. Credit: Greta Shum/Climate Central

The floats drift 1,000 meters below the surface. Every 10 days, they plunge a thousand meters deeper, then bob up to the surface before returning to their original depth.
For three years, 35 floats equipped with state-of-the-art sensors the size of a coffee cup have been collecting data along the way and beaming it back to the researchers, like Russell in Tucson. Within hours, the data is freely available online.
They measure ocean acidity, or pH, and other metrics to understand the biogeochemistry of the elusive ocean, but not without controversy.

Making a splash
Alison Gray, an oceanographer at the University of Washington, is the lead author on the study. She said there are two reasons the study may contradict what has previously been thought of about the Southern Ocean: The lack of winter-time observations at the ocean by other researchers and the fact that ocean carbon levels might vary throughout the year.
So while SOCCOM is making it possible to get more data than ever before, others question her nontraditional methods. They suggest that Gray’s alarming results are derived from error.
“Whether the Southern Ocean is absorbing a large quantity of CO2 from the atmosphere is a hot topic for environmental science and global policy making,” said Taro Takahashi, a geochemist from Columbia University, in an email. He is not involved with SOCCOM.
Takahashi is not entirely convinced the measurements reported by the authors are scientifically reliable enough to support their conclusions.
The issue with the findings is that researchers are not directly measuring CO2 but rather calculating it from the measurements taken with the new sensors, he said. The standard shipboard sensors don’t work at the depth the floats operate, and the traditional sensors are too large to fit on a float.

Pushback
Publishing the paper has been laborious as well, Russell said.
SOCCOM is like the disruptive startup in the carbon counting industry.
“(Reviewers) kept saying, ‘It’s a new sensor, so if you want us to trust it, we want more time and more of them,’ which is legitimate and annoying,” she said.
Additionally, while the floats are convenient year-round tools, some worry the floats will render measurements made by shipboard crews with the older, larger sensors obsolete. But Russell wants to reassure them: "We don’t think we should ever replace the ships because that together actually gets us this transformational science.”

The N.B. Palmer research vessel carried scientists across the Southern Ocean as they collected samples and launched floats, which remotely monitor ocean conditions. Credit: Ted Blanco/Climate Central

What’s next
Gray remains confident in her findings, "but we need to keep making measurements to verify our results," she said.
“Even assuming large uncertainty, our results are still significantly different than previous estimates," Gray said. "So even if we are off, the take-home message is the same."
The team only wants to improve the models with more data so that future climate predictions can bet more accurate, Gray said.
“If the Southern Ocean is not taking up as much carbon as we believed, it could be that things are changing more rapidly,” Wanninkhof said.
And that matters, even in a desert thousands of miles from the Antarctica since climate change will make extreme weather events more extreme in Arizona, he said.

Links

• End Of The Journey For Iceberg B-15?
• Global Warming Is Melting Antarctic Ice From Below
• One Of The Scariest Effects Of Climate Change Might Already Be Happening -- And It'd Mean Our Projections Are Way Off
• The Guardian View On Antarctica: The Worrying Retreat Of The Ice
• An Alarming 10 Percent Of Antarctica’s Coastal Glaciers Are Now In Retreat, Scientists Find
• Underwater Melting Of Antarctic Ice Far Greater Than Thought, Study Finds
• Inside Antarctica: The Continent Whose Fate Will Affect Millions
• This Dire Ocean Scenario Is A Stark Reminder Of Why The World Is Trying To Stop Climate Change

It's Hooray For Climate Scientists Day (Formerly Hug A Climate Scientist Day)

The Guardian - First Dog on the Moon

Links

• What Is It About Coal That Makes Old White Men So Crazy?
• The Billionaire's Guide To Surviving Global Warming – With Ian The Climate Denialist Potato
• Show This Cartoon To Anyone Who Doubts We Need Huge Action On Climate Change
• 'Last Year I Gave The Kids Briquettes And Everyone Yelled At Me!' Christmas With Ian

Geoengineering: The Quick, And Potentially Catastrophic, Fix For Climate Change

ABC - Michael Dulaney

Geo-engineering can involve putting reflective particles in the sky to reduce solar radiation. (clouds, Mattias, Flickr.com, CC BY 2.0)

Proposals for geoengineering projects sound like something out of science fiction.

Pumping aerosols into the upper atmosphere to make clouds more reflective, for example. Or fertilizing oceans with iron to promote the growth of plankton and algae so they consume more carbon dioxide.
Then there are proposals to plant vast swathes of trees in desert areas, or brighten clouds above marine areas to prevent ocean warming.
They sound like drastic interventions because that's what geoengineering is: the active and intentional modification of the climate.
As the Paris agreement target of limiting global temperature rise to two degrees or less seems increasingly improbable, there has been renewed interest in solutions that once seemed morally challenging, or difficult to contemplate.
To proponents, like Cambridge University's Hugh Hunt, geoengineering could mitigate the worst aspects of climate change, and provide time to look for more permanent solutions.
"It's a little bit like someone with lung cancer - we're not going to give you a transplant if you're going to carry on smoking," he said.
"Geoengineering will buy us some time, until we get this sorted out."

Dare not speak its name
Dr Hunt is currently investigating the construction of huge updraft towers in the desert, and using the air flows to generate electricity while stripping the airstream of greenhouse gasses.
He previously worked on a project named SPICE — Stratospheric Particle Injection for Climate Engineering — which looked at sending a tethered balloon 20km above to earth to seed aerosols into the stratosphere.
In theory, the particles would change the optical properties of sunlight, reflecting more solar radiation into space and reducing global temperatures.
The idea was to emulate natural volcanic events, like the 1991 eruption of Mount Pinatubo in the Philippines, which caused global cooling of one degree for about a year.

The Great Barrier Reef has struggled with two consecutive years of serious bleaching. (Supplied: Caitlin Seaview Survey 2015)

Intellectual property concerns were among the reasons SPICE and its balloon fell back to earth, figuratively speaking.
"It was closed down because it was deemed to be controversial," he said.
Dr Hunt is concerned about the lack of research into geoengineering solutions, which he says could leave the international community seriously unprepared if any country decided to act unilaterally.
"If they could be made to work, they could be quite cheap - the development time can be short, and the cost low," he said.

"It's like the Voldemort of climate change - it shall not be mentioned.

"My view is if something is going to be done, best we know how to do it safely. I think we should be allowing experiments, but I'm in a very small minority.

Adaptation on the Great Barrier Reef
They may seem far fetched, but geoengineering projects have already been proposed for areas in Australia's backyard.
One of the markers of global climate change is the health of the world's coral reefs, which are particularly sensitive to changing temperatures.


Aerial survey shows the extent of coral bleaching on section of Great Barrier Reef

Following two consecutive years of mass coral bleaching, a team of researchers at the Sydney Institute of Marine Science last year proposed altering the clouds above the reef in a bid to save the delicate coral communities below.
They advocated "marine cloud brightening", making larger and more reflective clouds over the ocean to cool the water underneath.
Great Barrier Reef Marine Park Authority (GBRMPA) chief scientist David Wachenfeld said the authority has already undertaken local action to improve the resilience of the reef to climate change, which he said was "far and away the greatest threat" to its survival.
Although they are much smaller in scope than those proposed by geoengineering advocates like Dr Hunt, Dr Wachenfeld said the GBRMPA had already looked at adaptation and marine park management to reduce human impact on the reef, include altering turtle nesting habitats to ensure greater numbers survive each year.
"These areas can certainly still recover if we do the right thing in terms of global mitigation of climate change and local actions to improve resilience," he said.
"We need to try harder, do more and act now."

'What happens if we screw it all up?'
Summer ice in the Arctic is now so thin that researchers last year sailed in small yachts rather than large ice breaking ships.
Scientists say as much as 50 gigatons of methane trapped under the Arctic could be released into the atmosphere if — or when — the protective permafrost completely melts, rapidly speeding up global climate change.

Ice is disappearing from the Arctic. (Kathryn Hansen/NASA)

The upshot of this and other climatic developments, according to Dr Hunt, is the need to urgently look at solutions that would otherwise seem unthinkable.
But he is not closed to the very real risk of catastrophe that geoengineering poses, pointing out that there are "hundreds" of potential adverse impacts. Most importantly, there is no "Planet B" if we get it wrong.
"The obvious ones are pumping something up high into the atmosphere and we know so little about the upper atmosphere - whatever we put up there has got to be safe," he said.
"What happens if we screw it all up? What happens if we accidentally switch off the Indian monsoon?"
Besides this, there is the risk the projects do not work at all, or are not as effective as advertised.
But Dr Hunt said this required more research and thought applied to the topic.

"I don't know which is worse - a seven metre sea level rise or geoengineering.

"That's putting it in a very pointed way, but we've got to think hard about this.
"It could be that there should be absolutely no way we ever do this. But that's why we've got to do the research."

Links

• Billion-Dollar Polar Engineering ‘Needed To Slow Melting Glaciers’
• How Engineering Earth’s Climate Could Seriously Imperil Life
• Scientists Look To Bali Volcano For Clues To Curb Climate Change