Arctic Nearly Free of Summer Sea Ice During First Half of 21st Century, Experts Predict
Apr. 12, 2013 — For scientists studying summer sea ice in the Arctic, it’s not a question of “if” there will be nearly ice-free summers, but “when.” And two scientists say that “when” is sooner than many thought — before 2050 and possibly within the next decade or two.
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James Overland of NOAA’s Pacific Marine Environmental Laboratory and Muyin Wang of the NOAA Joint Institute for the Study of Atmosphere and Ocean at the University of Washington, looked at three methods of predicting when the Arctic will be nearly ice free in the summer. The work was published recently online in the American Geophysical Union publication Geophysical Research Letters.
“Rapid Arctic sea ice loss is probably the most visible indicator of global climate change; it leads to shifts in ecosystems and economic access, and potentially impacts weather throughout the northern hemisphere,” said Overland. “Increased physical understanding of rapid Arctic climate shifts and improved models are needed that give a more detailed picture and timing of what to expect so we can better prepare and adapt to such changes. Early loss of Arctic sea ice gives immediacy to the issue of climate change.”
“There is no one perfect way to predict summer sea ice loss in the Arctic,” said Wang. “So we looked at three approaches that result in widely different dates, but all three suggest nearly sea ice-free summers in the Arctic before the middle of this century.”
Overland and Wang emphasized that the term “nearly” ice free is important as some sea ice is expected to remain north of the Canadian Archipelago and Greenland.
•The “trendsetters” approach uses observed sea ice trends. These data show that the total amount of sea ice decreased rapidly over the previous decade. Using those trends, this approach extrapolates to a nearly sea ice-free Arctic by 2020.
•The “stochasters” approach is based on assuming future multiple, but random in time, large sea ice loss events such as those that occurred in 2007 and 2012. This method estimates it would take several more events to reach a nearly sea ice-free state in the summer. Using the likelihood of such events, this approach suggests a nearly sea ice-free Arctic by about 2030 but with large uncertainty in timing.
•The “modelers” approach is based on using the large collection of global climate model results to predict atmosphere, ocean, land, and sea ice conditions over time. These models show the earliest possible loss of sea ice to be around 2040 as greenhouse gas concentrations increase and the Arctic warms. But the median timing of sea ice loss in these models is closer to 2060. There are several reasons to consider that this median timing of sea ice loss in these models may be too slow.
“Some people may interpret this to mean that models are not useful. Quite the opposite,” said Overland. “Models are based on chemical and physical climate processes and we need better models for the Arctic as the importance of that region continues to grow.”
Taken together, the range among the multiple approaches still suggests that it is very likely that the timing for future sea ice loss will be within the first half of the 21st century, with a possibility of major loss within a decade or two.
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Twitter tiff: Malcolm Turnbull and Kevin Rudd. Photo: Nic Walker
Experts sceptical of Coalition’s NBN plan
Would-be leaders Malcolm Turnbull and Kevin Rudd had a Twitter skirmish on Saturday in the battle of the broadband policies for their respective parties.
It started on Friday when @KRuddMP tweeted about living five kilometre from Brisbane: “Under Abbott, much of my community gets zero upgrade”.
By 10am on Saturday, @TurnbullMalcolm took him to task: “@KRuddMP not correct Our plan will improve your area’s bband speeds by taking it from adsl to vdsl most wd have 50 megs – 25 is the minimum.” (Translation better speeds are achievable by changing the digital line type).
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Then it was on – tweet-for-tweet – between the two MPs and a third party, the anonymous tweeter @geeksrulz.
@geeksrulz chimed in at 10.18am with: “@TurnbullMalcolm Your 25 to 50 are not achievable over 5kms from exchange via copper @KRuddMP.”
In a retaliatory missive, the Opposition communication’s spokesman, Mr Turnbull replied at 10.22am: “@geeksrulz @kruddmp 25 is the minimum. vdsl fttn (fibre to the node) delivers much higher speeds for most customers.”
Then Mr Turnbull reloaded at 11.16am: “@geeksrulz @kruddmp of course. That’s why you take the fibre further into field and so reduce cu (copper) length considerably.”
Mr Rudd, the former prime minister, got back into the fray at 11.37am: “@TurnbullMalcolm Hi Malcolm. Mate, so for 75% our cost, you get 25% the speed, a $5k hit per household, and its up a year before ours?”
Then he fired again at 12.04pm: “@TurnbullMalcolm Malcolm, if it looks like a sloth, moves like sloth, it probably is a sloth of a policy. I like sloths. But not for BB.”
Firing back, Mr Turnbull replied at 12.13: “@KRuddMP a sloth wd be ashamed by your NBN project which after four years hasn’t even managed to activate 20,000 premises.”
Stand-up comedian and cartoonist Jason Chatfield got the last word: “Thanks for giving us cartoonists some material for tomorrow. Cheers.”
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Climate change could get worse quickly if huge amounts of extra heat absorbed by the oceans are released back into the air, scientists said after unveiling new research showing that oceans have helped mitigate the effects of warming since 2000.
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By Environment Correspondent Alister Doyle
OSLO (Reuters) – Climate change could get worse quickly if huge amounts of extra heat absorbed by the oceans are released back into the air, scientists said after unveiling new research showing that oceans have helped mitigate the effects of warming since 2000.
Heat-trapping gases are being emitted into the atmosphere faster than ever, and the 10 hottest years since records began have all taken place since 1998. But the rate at which the earth’s surface is heating up has slowed somewhat since 2000, causing scientists to search for an explanation for the pause.
Experts in France and Spain said on Sunday that the oceans took up more warmth from the air around 2000. That would help explain the slowdown in surface warming but would also suggest that the pause may be only temporary and brief.
“Most of this excess energy was absorbed in the top 700 meters (2,300 ft) of the ocean at the onset of the warming pause, 65 percent of it in the tropical Pacific and Atlantic oceans,” they wrote in the journal Nature Climate Change.
Lead author Virginie Guemas of the Catalan Institute of Climate Sciences in Barcelona said the hidden heat may return to the atmosphere in the next decade, stoking warming again.
“If it is only related to natural variability then the rate of warming will increase soon,” she told Reuters.
Caroline Katsman of the Royal Netherlands Meteorological Institute, an expert who was not involved in the latest study, said heat absorbed by the ocean will come back into the atmosphere if it is part of an ocean cycle such as the “El Nino” warming and “La Nina” cooling events in the Pacific.
She said the study broadly confirmed earlier research by her institute but that it was unlikely to be the full explanation of the warming pause at the surface, since it only applied to the onset of the slowdown around 2000.
THRESHOLD
The pace of climate change has big economic implications since almost 200 governments agreed in 2010 to limit surface warming to less than 2 degrees Celsius (3.6 F) above pre-industrial levels, mainly by shifting from fossil fuels.
Surface temperatures have already risen by 0.8 C. Two degrees is widely seen as a threshold for dangerous changes such as more droughts, mudslides, floods and rising sea levels.
Some governments, and skeptics that man-made climate change is a big problem, argue that the slowdown in the rising trend shows less urgency to act. Governments have agreed to work out, by the end of 2015, a global deal to combat climate change.
Last year was ninth warmest since records began in the 1850s, according to the U.N.’s World Meteorological Organization, and 2010 was the warmest, just ahead of 1998. Apart from 1998, the 10 hottest years have all been since 2000.
Guemas’s study, twinning observations and computer models, showed that natural La Nina weather events in the Pacific around the year 2000 brought cool waters to the surface that absorbed more heat from the air. In another set of natural variations, the Atlantic also soaked up more heat.
“Global warming is continuing but it’s being manifested in somewhat different ways,” said Kevin Trenberth, of the U.S. National Center for Atmospheric Research. Warming can go, for instance, to the air, water, land or to melting ice and snow.
Warmth is spreading to ever deeper ocean levels, he said, adding that pauses in surface warming could last 15-20 years.
“Recent warming rates of the waters below 700 meters appear to be unprecedented,” he and colleagues wrote in a study last month in the journal Geophysical Research Letters.
The U.N. panel of climate scientists says it is at least 90 percent certain that human activities – rather than natural variations in the climate – are the main cause of warming in recent decades.
(Reporting by Alister Doyle, Environment Correspondent; Editing by Peter Graff)
Reuters
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1. sault 03:53 PM 4/7/13
We need to reduce greenhouse gas emissions ASAP. Since fossil fuel pollution damages the environment, harms our health and these fuels will eventually run out, climate change is just another reason to start the switch over to alternatives as fast as possible. Even without accounting for the costs of pollution, solar, wind and a whole host of clean energy technologies are becoming just as cheap as dirty fossil fuels. All we need is to ignore all the bellyaching from the people who have gotten very rich polluting our environment with fossil fuel waste and make the transition into a clean and sustainable 21st Century.
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2. jrfk2 04:10 PM 4/7/13
Unfortunately our foresight only seems to extend as far as our hands … when the inter-twined systems that humans depend on start breaking down .. then there will be a mad scramble to “fix” it .. then there will be a mad scramble to control the remaining clean water .. then it will just be mad. Then it will be the ants’ turn.
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3. Carlyle 05:45 PM 4/7/13
But but but…the AGW adherants have been adamant that there has been no pause. We must gird ourselves immediately for imminent hurricanes, cyclones, floods, drought, earthquakes, tsunamis, extinctions, disease, millions of climate refugees, & many other catastrophes.
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4. geojellyroll 07:19 PM 4/7/13
“Warmth is spreading to ever deeper ocean levels, he said, adding that pauses in surface warming could last 15-20 years.”
Too funny. Already making excuses why surface temperatures cooled in 2012 and the doomsday scenarios predicted in the 90’s have fallen flan…’climate models’…ya, sure.
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5. robmo 07:20 PM 4/7/13
More excuses for why the numbers don’t match the hype form the Global Warming crowd. In addition, there’s no way on God’s green earth that these ideologues will be able to link CO2 output to any warming, unless of course, they fudge the data which they tend to be very fond of doing.
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6. sault in reply to Carlyle 10:39 PM 4/7/13
Silly Carlyle, reading comprehension is for non-climate deniers!
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7. sault in reply to robmo 10:43 PM 4/7/13
So, you guys are denying the OBSERVED spectral properties of CO2 now? Seriously, lay off the fossil fuel propaganda a little and read some REAL science. Google Scholar has all the papers you’ll ever need.
http://scholar.google.com/scholar?as_ylo=2009&q=CO2+greenhouse+effect&hl=en&as_sdt=0,5
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8. sault in reply to geojellyroll 10:45 PM 4/7/13
Classic ignorance on climate science coming from the denier camp. You know that you can’t make a determination on whether temperatures “cooled” with just 1 year of data, right?
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9. Dr. Strangelove 10:46 PM 4/7/13
Easy to check if heat is spreading to deep oceans. Is the decadal sea level rise increasing or decreasing? Increasing means warming, decreasing means cooling. If the Antarctic ice sheet is not melting, then sea level rise must be due to thermal expansion of seawater.
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10. sault in reply to Carlyle 01:37 AM 4/8/13
You REALLY have to look at what’s ACTUALLY going on in the real world. This video about arctic sea ice ,ight help:
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EXCLUSIVE
Rocco Fazzari
Illustration: Rocco Fazzari
Ousted minister Simon Crean has given a scathing assessment of Prime Minister Julia Gillard’s ability to lead the country, in a signal that Labor’s leadership crisis is far from over.
He described Ms Gillard as having a ”tin ear” for sound political strategy and engaging in ”class warfare” by playing off interest groups, echoing opposition criticisms of Ms Gillard’s position on removing payments to middle class recipients.
Defying the Prime Minister’s demand for unity in her government, Mr Crean said he would continue to campaign for Labor to return to the proud traditions established by former Labor leaders Bob Hawke and Paul Keating.
Mr Crean also said federal Labor was deluding itself that it was in trouble in the polls solely because of destabilisation by Kevin Rudd. “I’ve been through destabilisation,” when he was Labor leader in 2001-03, “and we never went this low.”
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During an extensive interview, Mr Crean reopened wounds that were supposedly healing after his failed attempt to install Mr Rudd as prime minister in March.
Mr Crean, until then a minister in every Labor cabinet of the past 23 years, argued Ms Gillard was not living up to the principles of consensus and inclusiveness established by Mr Hawke and Mr Keating.
“She’s gone the class warfare. The 457 visa debate was a good example of the message being taken out of context – because it looked like we’ll put Australians before foreigners. Unequivocally, immigration has been good for this country,” Mr Crean said.
“That’s not the ethos of the Hawke-Keating model. How have we built the country? By cohesion. We are seen outside as the great success story of multiculturalism. Why don’t we play to it? Play to strength! That’s my point.”
Asked why he thought Ms Gillard was pursuing divisions, Mr Crean said that his leader had a political “tin ear”, and that she was in pursuit of headlines.
“You see, you have the conversations – that’s why I think she’s got a real tin ear – he [Kevin Rudd] was just arrogant but she’s got a tin ear. She sits there – ‘Mmm’ – and listens but it doesn’t translate.
“Because somewhere along the way she gets the word that here’s the angle on how you get tomorrow’s headline.”
Mr Crean also said that Ms Gillard needed to do more work on her two biggest election campaign promises – a national disability insurance scheme, and the Gonski school reforms.
“How do you have a national disability insurance scheme that doesn’t have people paying an insurance premium?” he posed.
“Why not use the argument of one of the other great Labor legacies that’s worked for this country – universal health cover – to justify it?” he said, a reference to the Medicare levy paid by taxpayers.
And the Gonski reforms needed to be better defined, he said. “You can’t just say we’re committed to Gonski ’cause no one knows what Gonski is.”
Ms Gillard sacked Mr Crean from her cabinet and submitted herself to a party room ballot for the leadership in March. But Mr Rudd declined to contest. Mr Crean said that Mr Rudd was now “finished”.
Mr Crean gave examples where the Gillard government had fomented resentment, pitting the wealthy against the workers, and foreign workers against local workers.
Ms Gillard has said the scheme to bring workers into Australia on work permits – 457 visas – was being rorted. She pledged to put “Aussie workers first”.
Mr Crean also said that some tension over gender was “part of this argument about division – because it’s easier to relate with one side against the other rather than get out there and try and cohere around a message that seeks to persuade in the national interest”.
Let’s stop hiding behind recycling and be honest about consumption
We have offshored the problem of escalating consumption, and our perceptions of it, by considering only territorial emissions
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Consumption and emissions : a textile manufacturing factory in Beijing , China
A Chinese factory worker operates a loom at a textile manufacturing factory in Beijing. Photograph: How Hwee Young/EPA
Every society has topics it does not discuss. These are the issues which challenge its comfortable assumptions. They are the ones that remind us of mortality, which threaten the continuity we anticipate, which expose our various beliefs as irreconcilable.
Among them are the facts which sink the cosy assertion, that (in David Cameron’s words) “there need not be a tension between green and growth”.
At a reception in London recently I met an extremely rich woman, who lives, as most people with similar levels of wealth do, in an almost comically unsustainable fashion: jetting between various homes and resorts in one long turbo-charged holiday. When I told her what I did, she responded: “Oh I agree, the environment is so important. I’m crazy about recycling.” But the real problem, she explained, was “people breeding too much”.
I agreed that population is an element of the problem, but argued that consumption is rising much faster and – unlike the growth in the number of people – is showing no signs of levelling off. She found this notion deeply offensive: I mean the notion that human population growth is slowing. When I told her that birth rates are dropping almost everywhere, and that the world is undergoing a slow demographic transition, she disagreed violently: she has seen, on her endless travels, how many children “all those people have”.
As so many in her position do, she was using population as a means of disavowing her own impacts. The issue allowed her to transfer responsibility to others: people at the opposite end of the economic spectrum. It allowed her to pretend that her shopping and flying and endless refurbishments of multiple homes are not a problem. Recycling and population: these are the amulets people clasp in order not to see the clash between protecting the environment and rising consumption.
In a similar way, we have managed, with the help of a misleading global accounting system, to overlook one of the gravest impacts of our consumption. This too has allowed us to blame foreigners – particularly poorer foreigners – for the problem.
When nations negotiate global cuts in greenhouse gas emissions, they are held responsible only for the gases produced within their own borders. Partly as a result of this convention, these tend to be the only ones that countries count. When these “territorial emissions” fall, they congratulate themselves on reducing their carbon footprints. But as markets of all kinds have been globalised, and as manufacturing migrates from rich nations to poorer ones, territorial accounting bears ever less relationship to our real impacts.
While this is an issue which affects all post-industrial countries, it is especially pertinent in the United Kingdom, where the difference between our domestic and international impacts is greater than that of any other major emitter. The last government boasted that this country cut greenhouse gas emissions by 19% between 1990 and 2008. It positioned itself (as the current government does) as a global leader, on course to meet its own targets, and as an example for other nations to follow.
But the cut the UK has celebrated is an artefact of accountancy. When the impact of the goods we buy from other nations is counted, our total greenhouse gases did not fall by 19% between 1990 and 2008. They rose by 20%. This is despite the replacement during that period of many of our coal-fired power stations with natural gas, which produces roughly half as much carbon dioxide for every unit of electricity. When our “consumption emissions”, rather than territorial emissions, are taken into account, our proud record turns into a story of dismal failure.
There are two further impacts of this false accounting. The first is that because many of the goods whose manufacture we commission are now produced in other countries, those places take the blame for our rising consumption. We use China just as we use the population issue: as a means of deflecting responsibility. What’s the point of cutting our own consumption, a thousand voices ask, when China is building a new power station every 10 seconds (or whatever the current rate happens to be)?
But, just as our position is flattered by the way greenhouse gases are counted, China’s is unfairly maligned. A graph published by the House of Commons Energy and Climate Change Committee shows that consumption accounting would reduce China’s emissions by roughly 45%. Many of those power stations and polluting factories have been built to supply our markets, feeding an apparently insatiable demand in the UK, the US and other rich nations for escalating quantities of stuff.
The second thing the accounting convention has hidden from us is consumerism’s contribution to global warming. Because we consider only our territorial emissions, we tend to emphasise the impact of services – heating, lighting and transport for example – while overlooking the impact of goods. Look at the whole picture, however, and you discover (using the Guardian’s carbon calculator) that manufacturing and consumption is responsible for a remarkable 57% of the greenhouse gas production caused by the UK.
Unsurprisingly, hardly anyone wants to talk about this, as the only meaningful response is a reduction in the volume of stuff we consume. And this is where even the most progressive governments’ climate policies collide with everything else they represent. As Mustapha Mond points out in Brave New World, “industrial civilisation is only possible when there’s no self-denial. Self-indulgence up to the very limits imposed by hygiene and economics. Otherwise the wheels stop turning”.
The wheels of the current economic system – which depends on perpetual growth for its survival – certainly. The impossibility of sustaining this system of endless, pointless consumption without the continued erosion of the living planet and the future prospects of humankind, is the conversation we will not have.
By considering only our territorial emissions, we make the impacts of our escalating consumption disappear in a puff of black smoke: we have offshored the problem, and our perceptions of it.
But at least in a couple of places the conjuring trick is beginning to attract some attention.
On 16 April, the Carbon Omissions site will launch a brilliant animation by Leo Murray, neatly sketching out the problem*. The hope is that by explaining the issue simply and engagingly, his animation will reach a much bigger audience than articles like the one you are reading can achieve.
(*Declaration of interest (unpaid): I did the voiceover).
On 24 April, the Committee on Climate Change (a body that advises the UK government) will publish a report on how consumption emissions are likely to rise, and how government policy should respond to the issue.
I hope this is the beginning of a conversation we have been avoiding for much too long. How many of us are prepared fully to consider the implications?
HAVANA — Cuba risks losing a vast stretch of beach front homes and pristine coastal habitat by 2050, because of rapidly rising sea levels, a top environmental official warned Thursday.
At a panel discussion on Cuban environmental policy, Tomas Escobar, director of the island’s National Environment Agency, said rising oceans could submerge huge areas of the Caribbean island, with potentially devastating consequences.
The changes “could affect ecosystems, increase the vulnerability of coastal settlements, reduce agricultural soil productivity, crops and forestry and reduce the quality and availability of water,” the Prensa Latina news agency quoted Escobar as saying.
“At the current rate of increase in sea level, by 2050 we will have lost nearly 2,700 square kilometers of land area and 9,000 homes,” he said.
Cuba has an area of 109,884 square kilometers (42,426 square miles), and more than 5,700 kilometers (3,500 miles) of coastline that includes everything from steep cliffs to sandy beaches to swamps.
Escobar said President Raul Castro’s government had established a policy to try and mitigate the effects of rising sea levels, centered on “the goal of reducing vulnerabilities identified in disaster prevention studies.”
Policy priorities include the conservation and rehabilitation of coastal ecosystems, including the island’s coral reefs, mangroves and beaches.