Search Results for Tag: Arctic
Greenland melt natural or man-made?
And does it ultimately make any difference? Scientists from the University of Washington (UW) have published a paper in Nature estimating that up to half of the recent warming in Greenland and surrounding areas may be due to climate variations that originate in the tropical Pacific and are not connected with the overall warming of the planet. You can just hear the “I told you so”, from the climate skeptics. “Still”, the UW scientists add, “at least half the warming remains attributable to global warming caused by rising carbon dioxide emissions”.
With all due respect to the scientists who do this essential research – I repeatedly find myself wondering how we can talk about “natural” climate variations at all any more, given that we have changed the parameters so much you could argue none of it is really without human impacts. Does natural fluctuation not act differently if you are starting from completely different base data, brought about by man-made warming through greenhouse gas emissions?
Greenland and parts of neighboring Canada have experienced some of the most extreme warming since 1979, at a rate of about 1 degree Celsius per decade, or twice the global average, the scientists say. “We need to understand why in the last 30 years global warming is not uniform”, says first author Qinghua Ding, a UW atmospheric research scientist. “Superimposed on this global average warming are some regional features that need to be explained”.
The study uses both observations and advanced computer models. It comes to the conclusion that a warmer western tropical Pacific Ocean has caused atmospheric changes over the North Atlantic that have warmed the surface by about half a degree per decade since 1970. “The pattern of the changes in the tropical Pacific that are responsible for remarkable atmospheric circulation changes and warming in Greenland and the Canadian Arctic are consistent with what we would call natural variability”, says co-author David Battisti, a UW professor of atmospheric sciences.
Of course there will always be natural variability in the course of the seasons and changing meteorological conditions. But in many of the fastest—warming areas on earth, co—author of the new study John “Mike” Wallace, also professor at UW, says global warming and natural variations combine to create a “perfect storm” for warming.
The scientists attribute the natural variations in their study to an “unusually warm western tropical Pacific, near Papua New Guinea. Sind the mid-1990s the water surface there has been about 0.3 degrees hotter than normal. Computer models show this affects the regional air pressure, setting off a stationary wave in the atmosphere that arcs in a great circle from the tropical Pacific toward Greenland before turning back over the Atlantic”. Wallace says there are warm spots where the air has been pushed down, and cold spots where the air has been pulled up. And Greenland, he explains, is in one of the warm spots”.
This and other research by these scientists has documented the existence of decades-long climate variations in the Pacific Ocean which resemble the better known shorter-range El Nino variations. Other studies have indicated that waves starting in the same place in the tropical Pacific but radiating southward are warming West Antarctica and melting the Pine Island Glacier, which has been the subject here on the Ice Blog before.
The experts describe this natural variation as “unpredictable”, whereas the half of the warming in Greenland from the “forcing of climate by anthropogenic greenhouse gases” is “predictable”.
So what do we learn from all of this? One thing is clear. It does NOT change the threat to Greenland’s ice from our man-made warming: “Nothing we have found challenges the idea that globally, glaciers are reatreating, says Battisti. “Ice appears to be exquisitely sensitive to the buildup of greenhouse gases, more than we ever would have thought”, says his colleague Wallace.
Ultimately, the researchers say, natural variations could either accelerate or decelerate the melting rate of Greenland’s glaciers in coming decades. But, “in the long run, the human induced component is likely to prevail”.
So don’t let anybody use this as an excuse to talk down the need to cut emissions in a big way asap.
DateMay 7, 2014 | 4:09 pm
Will Antarctic share Arctic’s fate?
While the Arctic is melting twice as fast as the rest of the planet, and protests continue against the race for oil at huge risk to the sensitive environment, the icy regions around the south pole were long considered immune to climate change. But melting glaciers on the Antarctic Peninsula in recent years sparked doubts in the scientific community about just how stable the western region of Antarctica really is. Earlier this year, I wrote an article on the irreversible melt of the Pine Island glacier on western Antarctica. The huge iceberg that broke off last November has been in the news again, heading for the open sea.
Only the huge icy vastness of Eastern Antarctica still appeared to be safe from the perils of a warming climate. Now experts from Germany’s Potsdam Institute for Climate Impact Research (PIK) have published findings indicating that this too might no longer be the case. In a study published in “Nature Climate Change“, they write that the melting of just a small volume of ice on the East Antarctic coast could ultimately trigger a discharge of ice into the ocean which would result in unstoppable sea-level rise. They are talking about tomorrow or the next decade. Still, the prospect of more irreversible thawing in the Antarctic is a very worrying one.
“Previously, only the West Antarctic was thought to be unstable. Now we know that the eastern region, which is ten times bigger, could also be at risk”, says Anders Levermann, co-author of the study. The findings are based on computer simulations which make use of new, improved data from the ground beneath the ice sheet.PIK scientist Levermann was one of the lead authors of the sea-level section in the latest IPCC report.
“The Wilkes Basin in East Antarctic is like a bottle that is tilted”, says Matthias Mengel, lead author of the new study.”If you take out the cork, the contents will spill out”. At the moment, the “cork” is formed by a rim of ice at the coast. If that were to melt, the huge quantities of ice it holds back could shift and flow into the ocean, raising sea levels by three to four meters. Although air temperatures over Antarctica are still very low, warmer ocean currents could cause the ice along the coast to melt.
So far, there are no signs of warmer water of this sort heading for the Wilkes Basin. Some simulations suggest though that the conditions necessary for the “cork” to melt could arise within the next 200 years. Even then, the scientists say it would take around 2000 years for sea level to rise by one meter.
According to the simulations, it would take 5,000 to 10,000 years for all the ice in the affected region to melt completely. “But once this has started, the discharge will continue non-stop until the whole basin is empty”, says Mengel. “This is the basic problem here. By continuing to emit more and more greenhouse gases, we could well be triggering reactions today that we will not be able to stop in the future. ” Indeed.
The IPCC report predicts a global sea-level rise of up to 16 centimeters this century. As this could already have devastating impacts on many coastal areas around the globe, any additional factor is of key importance to the calculations. “We have presumably overestimated the stability of East Antarctica”, says Levermann. Even the slightest further increase in sea level could aggravate flooding risks for coastal cities like New York, Tokyo or Mumbai.
At the moment, the largest contribution to Antarctic ice loss and rising sea levels comes from the Pine-Island glacier in West Antarctica. As I mentioned at the start, a huge iceberg, which broke off from the glacier last year, is currently floating into the open waters of the Southern Ocean. French glaciologist Gael Durand from Grenoble University told me in an interview the huge glacier had already reached a point where its continued melting is irreversible, regardless of air temperature or ocean conditions.
DateMay 5, 2014 | 2:51 pm
Arctic oil: confrontations ahead?
The first oil from the controversial Prirazlomnaya offshore Arctic oil platform is on its way to Rotterdam. This, you will remember, was the oil rig where the Greenpeace “Arctic 30” were arrested by Russian forces last September during a protest. The Greenpeace ship Rainbow Warrior III is on its way to meet the tanker, the “Mikhail Ulyanov”, and protest against Arctic oil drilling. (The Greenpeace icebreaker Arctic Sunrise remains in the custody of the Russian Investigative committee, over six months after the action and four months since an official amnesty was adopted).
This oil transport marks the first ever shipment of Arctic offshore oil. Interestingly, it has been bought by the French oil concern Total SA. I remember the furore when the chief executive of that very company Christophe de Margerie, ruled out drilling in the Arctic in 2012 out of concern about the effect of a possible spill. Hm. Looks like it’s OK to profit from the oil as long as somebody else takes the risk. Although I seem to remember at the time that worry about the negative impact a spill in the sensitive ecosystems of the remote Arctic would have on the image of the industry as a whole played a role in the decision.
Greenpeace Captain Peter Willcox, a member of the ‘Arctic 30’ who was imprisoned in Russia for over two months after the protest at Gazprom’s Prirazlomnaya platform in the Pechora Sea last year, is at the helm of the Rainbow Warrior III. The organization is not saying much about what form the protest will take as yet. But presumably the risks of a drastic response like last year’s Russian crack-down are minimal in the North Sea. As far as the culture of dealing with protest in the Arctic is concerned however, a recent announcement by President Putin gives little reason for optimism. On April 23rd, the Barents Observer carried a worrying report headlined “Putin arms Arctic drillers” on a meeting between Putin and his top national security aides. It says Putin highlighted the need for an enhanced security presence in Russian Arctic territories to protect oil production facilities, loading terminals and pipelines “against terrorists and other potential threats”.
The same day Putin signed amendments in a federal law on the protection of oil and gas objects and infrastructure. It gives Russian oil companies the right to establish their own protection units. The Barents Observer quotes the newspaper Rossiskaya Gazeta as suggesting the companies might eventually hire “thousands of well-armed people, equipped with automatic weapons, vehicles, vessels and aircraft”, mostly former military personnel, police officers and special forces agents. Even if that proves to be slightly exaggerated: the thought of corporate armed units having the law in their own hands to squash anything that looks like opposition to Arctic development is a nightmare.
“This week’s Arctic speech from the Russian leader has a scope which goes far beyond imagined threats from potential terrorists. It also includes a major element of heightened inter-state tensions”, according to the Barents Observer. Given the current climate against the background of the ongoing Ukraine conflict, I have to share that concern. With the Russian leader stepping up the country’s military presence in the Arctic arguing that there is an “increasing conflict of interest between the Arctic coastal states” and that “the situation in the world is fraught with new risks and challenges to Russian national interests”, it is hard to be optimistic about the prospects for an Arctic future free of confrontation.
DateApril 28, 2014 | 2:16 pm
Empowering Arctic Youth
Back in 2008, the Ice Blog was born when I was on a trip to Alaska reporting on the “Climate Change College”, a joint project by WWF and an ice cream company to interest young people in climate change. Young climate ambassadors from Europe had won a trip to Arctic Alaska to find out first hand about the impacts of climate change – and to meet with young people in the region. I am still in contact with some of the ex-ambassadors, who are continuing to make contributions to climate and environment protection in their careers and everyday lives. Cara Augustenborg in this photo is a successful academic, entrepreneur and Green Party candidate in Ireland. Kayan, I wonder if you are still in Alaska and if you ever got yourself an environment-friendly means of transport?
Anyway, I have Elías Thórsson from the Arctic Journal to thank for drawing my attention to a new youth project inside the Arctic: YAC, the Youth Arctic Coalition. It sees itself as “Youth collaboration to address environmental, economic and social challenges and opportunities in the Arctic”. The latest edition of the Arctic Journal has a story by Elías on the group and the need to include young people in decisions on Arctic issues, headlined “Carpe Arcticum”.
Indeed, the Arctic is one of the fastest changing places on the planet. With countries as far away as China or Japan making their interest(s) plain, what happens in the Arctic today will have a huge impact to the region future generations in the High North will inherit.
During my latest visit to Arctic Norway in January, young protesters in Tromso told me of their fears about the environmental impacts of Arctic oil drilling. During visits to Alaska, I spoke to young Inupiat residents who were more concerned about jobs and hoping to continue to benefit from wealth from the oil industry. In Greenland, some of the youngsters I spoke to were torn between concern about the melting ice and changes to the lifestyle they had grown up with, and the hope that climate change might bring jobs and prosperity to their Arctic island.
The YAC, which held its inaugural conference in February, is trying to bring young people from across the Arctic together to have their say in what is happening. It is not an easy task, as Elías explains in the article. Clearly, views amongst young people will cover as wide a spectrum as those of any other generation. But they will be united in their interest in looking beyond the short-term interests which influence business and politics today.
So good luck to YAC and here’s hoping your organization will attract a lot of interest. And that it will inspire a lot of active participation to shape a sustainable future for the Arctic and represent the interests of coming generations in a region in danger of losing its identity amidst the ever-faster changes caused by a warming climate.
DateApril 25, 2014 | 3:08 pm
Greenland’s icecap losing stability
Catching up on the last few weeks of icy news after a spring holiday, my eye was caught by an item by Tim Radford from the Climate News Network, dated April 13th. I quote: “Greenland is losing ice from part of its territory at an accelerating rate, suggesting that the edges of the entire ice cap may be unstable”. This caught my attention not just because anything relating to Greenland tends to do that, but because the development could have major significance for the future world climate and sea level- and because it doesn’t seem to have made its way into the mainstream media at a time when sensitivity to the issue should have been high after the IPCC report.
The Greenland ice sheet is the largest terrestrial ice mass in the northern hemisphere. Radford draws attention to a study in Nature Climate Change by Shfaqat Khan from the Technical University of Denmark and colleagues, which indicates that the ice sheet could be melting faster than previously thought. This would mean Greenland’s contribution to sea level rise has been under-estimated (once again!), and oceanographers may need to think again about their projections.
The scientists used more than 30 years of surface elevation measurements of the entire ice sheet to discover that overall loss is accelerating. Previous studies had identified melting of glaciers in the island’s south-east and north-west, but the assumption had been that the ice sheet to the north-east was stable, Radford writes:
“It was stable, at least until about 2003. Then higher air temperatures set up the process of so-called dynamic thinning. Ice sheets melt every Arctic summer, under the impact of extended sunshine, but the slush on the glaciers tends to freeze again with the return of the cold and the dark, and since under historic conditions glaciers move at the proverbial glacial pace, the loss of ice is normally very slow.”
But with global warming, Greenland’s southerly glaciers have been in retreat and one of them, Jakobshavn Isbrae or Sermeq Kujalleq, is now flowing four times faster than it did in 1997. I first reported on this during a trip to Greenland in 2010, and have presented various new studies on it here on the Ice Blog since.
The new research by the Danish-led team considers changes linked to the 600 kilometre-long Zachariae ice stream in the north-east, using satellite measurements. It has retreated by some 20 kilometres in the last DECADE, whereas Sermeq Kujalleq has retreated about 35 kms in 150 years. The Zachariae stream drains around one-sixth of the Greenland ice sheet, and because warmer summers have meant significantly less sea ice in recent years, icebergs have more easily broken off and floated away, which means that the ice stream can move faster. “North-east Greenland is very cold. It used to be considered the last stable part of the Greenland ice sheet,” said one of the team, Michael Bevis of Ohio State University in the US, in an interview with the Climate News Network.
“This study shows that ice loss in the north-east is now accelerating. So now it seems that all of the margins of the Greenland ice sheet are unstable.”
The scientists used a GPS network to calculate the loss of ice. Glacial ice presses down on the bedrock below it: when the ice melts, the bedrock rises in response to the drop in pressure, and sophisticated satellite measurements help scientists put a figure on the loss of ice. They calculate that between April 2003 and April 2012, the region was losing ice at the rate of 10 billion tons a year.
“This implies that changes at the margin can affect the mass balance deep in the centre of the ice sheet,” said Dr Khan. Sea levels are creeping up at the rate of 3.2 mm a year. Until now, Greenland had been thought to contribute about half a mm. The real figure may be significantly higher, according to the report.
This is a very worrying development, but it seems to me it did not get a lot of public attention. This brings me back to the question of the discrepancy between what we know about the impacts of climate change and the widespread lack of political and consumer action. (See my article Denial or Disconnect: Why don’t we act on climate change?)
Are people sticking their heads in the sand (or melting snow)? Have we just been assured so many times that the Greenland ice sheet will never melt that we don’t sit up and take notice? Is it too far away in time and space to bother us? Are too many people giving up and resigning themselves to the fact that climate change is inevitable? Is it just so much easier to hold on to the status quo instead of having to make changes to our 21st century lifestyles?
DateApril 22, 2014 | 2:38 pm