The Sermeq Kujualleq glacier discharges icebergs into the sea (I. Quaile, Ilulissat 2009)

It might sound like stating the obvious, but in fact it is not easy to find clear evidence that human behavior is behind the retreat of glaciers being monitored in different parts of the world. Hence my interest in a study just published in the journal Science.

The main problem is that it usually takes decades or even centuries for glaciers to adjust to climate change, says climate researcher Ben Marzeion from the Institute of Meteorology and Geophysics of the University of Innsbruck. He and his team of researchers have just published the results of a study for which they simulated glacier changes during the period from 1851 to 2010 in a model of glacier evolution. They used the recently established “Randolph Glacier Inventory” (RGI) of almost all glaciers worldwide to run the model, which included all glaciers outside Antarctica.

“Melting glaciers are an icon of anthropogenic climate change”, the authors say. However, they stress that the present-day glacier retreat is a mixed response to past and current natural climate variability and “current anthropogenic forcing”. Their modeling shows though that whereas only 25% of global glacier mass loss between 1851 and 2010 can be attributed to human-related causes, the fraction increases to around 69% looking at the period between 1991 and 2010. So human contribution to glacier mass loss is on the increase, the experts write.

Marzeion says the global retreat of glaciers observed today started around the middle of the 19^th century at the end of the Little Ice Age, responding both to naturally caused climate change of past centuries (like solar variability), and to human-induced changes. Until now, the real extent of human contribution was unclear. The authors say their latest piece of work provides clear evidence of the human contribution.

Once more I am happy to refer to the Climate News Network, in this case to Tim Radford, for an easy-to-read summary of the main research results and the background. There is no doubt that glaciers are losing mass, retreating uphill and melting at a faster rate, says Radford. He refers to some Andes glaciers and the the Jakobshavn glacier in Greenland, or Sermeq Kujualleq as I prefer to call it, using the indigenous name. Ice Blog followers may remember my own trip to Greenland and that particular glacier. I have also written on the speeding of the melt there on the Ice Blog and on the DW website.

Alpine glacier like these in Saas-Fee, Switzerland, have declined dramatically in recent decades. (I.Quaile)

Radford also refers to ascertaining the melting of alpine glaciers by comparing historic paintings and other documentation with the current ice mass. That decline is something I have observed at first hand in Valais in Switzerland during regular visits over the past 30 years. Look out for a comparative photo gallery of my own pics, when I get time to put it together. Since most of the shots are from the pre-digital era, that will be a time-consuming task.

I also remember a trip to the Visitor Centre of the Begich Boggs glacier in Alaska in 2008. The glacier has already retreated so far you can’t see it at all from the Centre built specially for the purpose of viewing it.

The question until now was how much of all this was caused by natural developments and how much to changes in land use and the emission of greenhouse gases? The latest study supported, among others, by the Austrian Science Fund (FWF) and the research area Scientific Computing at the University of Innsbruck, has come up with some answers. Since the climate researchers were able to include different factors contributing to climate change in their model, they can differentiate between natural and anthropogenic influences on glacier mass loss

“While we keep factors such as solar variability and volcanic eruptions unchanged, we are able to modify land use changes and greenhouse gas emissions in our models,” says Ben Marzeion, who sums up the study: “In our data we find unambiguous evidence of anthropogenic contribution to glacier mass loss.”

As always, there is still need for further research – and a lot more monitoring. The scientists say the current observation data is insufficient in general to derive any clear results for specific regions, even though anthropogenic influence is detectable in a few regions such as North America and the Alps, where glaciers changes are particularly well documented.

With global glacier retreat contributing to rising sea-levels, changing seasonal water availability and increasing geo-hazards, the study’s conclusions should help put a little more pressure on the world’s decision-makers to get serious about emissions reductions.

Laura Brosius collects methane from Eight Mile Lake using an “umbrella trap” (Pic: I.Quaile, 2008)

When the Ice Blog was launched in 2008, one of the first posts from a trip to Alaska entitled “Ice-Capades and Alaska baking with methane?” included a visit to frozen-over “Eight-mile Lake” in the Denali national park, where scientists Katey Walter and Laura Brosius were measuring methane emissions from melting ice and permafrost. The young “climate ambassadors” I was travelling with helped her to set up “umbrella traps” and capture bubbles of methane coming to the surface. The “proof of the pudding” was setting a match to the gas and watching it catch light. An interesting experiment.  But the subject has huge wide-ranging implications.  Methane is also a greenhouse gas 25 times more powerful than CO2. Walter and others have since recorded numerous methane seeps in Alaska and Greenland. As global temperatures increase, the permafrost thaws, potentially releasing the gas stored both in the permafrost on land and in the form of methane hydrates under water.

Since that Alaskan trip, methane has beconme an increasingly “hot topic”,  with more research being conducted and data collected. The reservoir of methane stored under the Arctic ice and permafrost is huge.  And there is increasing scientific evidence that with the world warming, this reservoir is not going to stay there for ever. The concentration of atmospheric methane has increased dramatically in the last 200 years – especially in the Arctic. In 2008, scientists came up with a scenario where up to 50 gigatonnes of methane could be released abruptly from the East Siberia Arctic Shelf (ESAS) because of the melting of permafrost which had hitherto kept it safely sealed in.

You can see the methane bubbles rising. (Pic I. Quaile)

Fountains of methane

In 2011, a joint US-Russian expedition surveying the seabed of the East Siberian Arctic Shelf off northern Russia was surprised to observe fountains of methane rising to the sea surface from beneath the seabed. At that time, scientists expressed concern that with the melting of Arctic sea ice and permafrost, the huge methane stores might be released over a relatively short period of time.

The SWERUS-C3 expedition headed by Örjan Gustafsson from Stockholm University is currently underway in the Laptev Sea, where they have discovered “vast methane plumes escaping from the seafloor of the Laptev continental slope”. Gustavsson writes in his blog that he was surprised by this. He speculates that it could have its origins in collapsing “methane hydrates”, clusters of methane trapped in frozen water due to high pressure and low temperatures.

“While there has been much speculation about the vulnerability of regular marine hydrates along the continental slopes of the Arctic rim, very few actual observations of methane releases due to collapsing marine hydrates on the Arctic slope have been made”, Gustafsson writes.  He thinks a “tongue” of relatively warm Atlantic water, presumably intruding across the Arctic Ocean at 200-600 meters depth could have something to do with the methane seeps. Some evidence shows this water mass has recently become warmer.

“As this warm Atlantic water, the last remnants of the Gulf stream, propagates eastward along the upper slope of the East Siberian margin, it may lead to the destabilization of methane hydrates on the upper portion of the slope”, Gustafsson writes.

Costly bubbles

In 2013,  a paper published in the journal Nature put a price tag on the possibility of the Arctic’s methane being released. The experts suggest it could trigger costs of 60 trillion US dollars. Normally, as soon as money is involved, public interest tends to rise. The report should really have brought  the subject of “Arctic methane hydrates” out of the science corner onto the economic and political agenda. Which is, of course, where it has to be, if there is any chance of limiting the Arctic thaw by halting global warming.

Investigating the huge amount of methane captured under Arctic permafrost. (Pic I. Quaile)

There are scientists who insist that such a scenario is not likely. Let me refer you here to a detailed analysis of the scientific literature on the subject published by Nafeez Ahmed, executive director of the Institute for Policy Research & Development, in EarthInsight hosted by the Guardian, in 2013. He points out that none of the scientists  who reject the plausibility of the scenario are experts in the Arctic, and specifically the ESAS. On the other hand, there is an emerging consensus among ESAS specialists based on continuing fieldwork, he writes, “highlighting a real danger of unprecedented quantities of methane venting due to thawing permafrost”.

Rhetoric, polemics – but accuracy please!

Ahmed comes down on the side of the Arctic experts who are highly concerned about the risk of methane being set free in large quantities. That is already clear from the title of his article “Seven facts you need to know about the Arctic methane timebomb”. Sub-headed: “Dismissals of catastrophic methane danger ignore robust science in favour of outdated mythology of climate safety.” Yes, you could say that is tendentious. It is certainly rhetorically powerful.

Perhaps that accounts in part for the reaction I got when I tweeted the link to his analysis recently as interesting background to the ongoing debate on Arctic methane. One response told me to stop “fear mongering” and referred to an article describing methane as a “climate boogeyman”. (In connection with studies on methane leaks from natural gas production). Aha. Emotions are running high – on both sides.

Still – Ahmed’s article is based on a thorough analysis of both sides of the arguments. It seems this cannot be said of a piece on news.com.au, headlined “Are Siberia’s methane blow-holes the first warning sign of unstoppable climate change?”. The article links three giant craters which have been found in Siberia to the scientific research of Jason Box, a renowned glaciology professor and Greenland expert, starting with the tantalizing question:

“What do three enormous craters in the Siberian wastelands have to do with a terrified American climate scientist? Methane. And that’s something to scare us all”.

In fact, as Jason Box @climate_ice tweeted to his followers, the Arctic expert’s research and concern have nothing to do with the giant craters. He tweets:

“News piece juxtaposes Siberian holes with my carbon release concerns but I have no idea about the holes”

Citing the concerns and findings of reputed scientists alongside other reported explanations of the Siberian craters as “hellmouths”, “gateways to the undead” or “aliens” does nothing for serious scientific attempts to monitor climate change in the Arctic or inform politicians and businesses about the scenarios for which the world has to prepare. Now if those of a skeptical persuasion were to take this kind of article as “fear mongering” or the “climate boogeyman”, I could just about understand it. Please, let us not detract from the value of scientific monitoring and analysis, complex computer modeling and genuine concern on the part of a lot of experts who know very well what they are talking about. And let us not bring the media into disrepute for misrepresenting the views of scientists like Jason Box by taking his findings and statements out of context in the interest of a sensationalist story. We do not need to mix fact with fiction and create “boogeymen”. The huge body of scientific findings out there is already scary enough.

Svalbard ice (Irene Quaile)

When a colleague who has a lot of sympathy for those who do NOT accept that humans are responsible for global warming drew attention to the fact that this had been the hottest June on record, following hard on the hottest May, I must admit I was temporarily put of my guard. Aha, I thought. Is he finally getting the message? Alas, the answer is no. There is a small minority of people that still argues – for whatever reason – that natural variation could be responsible for all this, while acknowledging the record concentration of CO2 in the atmosphere. “And all that stuff”. Hm.

Who would have believed it? It has been a long time since the routine UN climate talks in Bonn aroused much in the way of enthusiasm. Frustration or even despair were more likely the order of the day.

Since the debacle in Copenhagen in 2009, it has been hard to stir up any kind of optimism in the climate debate. The planet is heating up, CO2 emissions are still on the increase, the ice caps are melting, storms, floods and droughts are causing huge problems even for wealthy, industrialized nations.

At the same time the UN negotiations have been slithering along at glacial pace. One upon a time, that meant very slow. But with increasing warming, even the ice giants are on the move. The sea level is rising – and maybe even the UN climate talks are sliding into motion.

A glimmer of hope from the climate sinners?

In recent years, the UN summer meetings on the banks of the Rhine were at best good to fill a hole on a news-slack day. This time, it was different. Just before the talks started, US President Barack Obama got the “snowball” rolling with his announcement he would use the Environmental Protection Agency to impose tough restrictions on emissions from coal power plants.

It’s time for innovative solutions all round. Extreme weather at home has taught America to fear climate change. Obama wants climate action to be his legacy. That can only be a good thing for all of us.

Pam Pearson, Director of the International Cryosphere Climate Initiative told me people in her home state Florida are more aware of  the importance of the polar ice. (Pic: IQ)

When China then came out with the intention to cap its emissions, the world really had to sit up and take notice. Even the to-ing and fro-ing on how, why and when, or whether it was just the “personal opinion” of a high-ranking climate representative could not dampen the enthusiasm. For the first time ever, it looks as if the world’s two biggest emitters could actually be prepared to act.

Meanwhile more encouraging signs came out of India and Latin America.

Renewables on the ‘up’

At the start of the Bonn talks, a broad coalition of environment, human rights, indigenous and women’s groups demonstrated outside the conference venue for a worldwide switch to renewable energies. By the end of the talks, 60 countries had signaled support for a 100 percent switch by 2050. German Environment Minister Barbara Hendricks had to admit Germany was not making its targets right now, but would introduce new measures to reach its ambitious goal of a 40 percent emissions reduction by 2020.

If the EU could also bring itself to increase its targets and regain its old position as a climate leader, if the energy crisis caused by the Ukraine dispute could convince politicians that renewable energy is the key to energy security and independence, Europe could well be on its way to hosting a conference that will give birth to a new global agreement.

And even if the UN structures cannot move fast enough: renewable energies are on the rise. UNEP figures show more investment in renewables in the last year than in oil, coal and gas together. Even outside the UN context governments, companies and consumers are finding reason enough to reduce fossil fuel consumption. All is not yet lost for the melting icecaps. The climate snowball is gathering speed.

(I.Quaile)

… And the ice continues to melt. (Pic: I. Quaile)

The delegates to the UN climate meeting currently taking place here in Bonn are receiving an urgent appeal from polar scientists to cut emissions to slow polar ice melt and give low-lying coastal regions more time to adapt to rising sea levels.

I was very interested to hear about a side-event being held here this evening, at which the authors of this year’s key studies on developments in the Antarctic will be explaining the connections between melting polar ice and climate change impacts like rising seas, affecting regions as diverse as small island states, Bangladesh or Florida in the USA.

I interviewed Anders Levermann from PIK, the Potsdam Institute for Climate Impacts Research and Pam Pearson, Director of ICCI, the International Cryosphere Climate Initiative, both in Bonn for the event.

The ICCI decided to bring the cryosphere into the Bonn talks to sensitize delegates to the dramatic developments in the Antarctic in particular, says Pearson. Ice Blog readers (and I was so delighted to hear Pam herself is one!) will remember posts earlier this year on melting in the East and West Antarctic. I also covered these in articles for DW. The shocking thing is that the Antarctic, even East Antarctica, which was until relatively recently considered so cold it had to be safe from global warming, is already being affected by climate change. The papers on the West Antarctic even described the melt trend as “irreversible”.

“We have entered an era of irreversible climate change”.

Today, Anders Levermann, author of the East Antarctic paper and one of the world’s leading Antarctic researchers, told me “we have entered a new era of climate change, witnessed the tipping of the West Antarctic ice sheet, and this is irreversible”.

That should really shock people into action, you would think. But climate negotiations are moving, as one of the experts said to me at the meeting “at a glacial pace”. As we can see in Antarctica, though, and Greenland and other regions, those glaciers are speeding up. Maybe there is hope for the climate talks yet!

The announcements by the USA and China on possible emissions cuts have brought a new “buzz” to the Bonn conference. The fact that the key emitters could finally be getting the message and preparing to move, with the impacts of climate change hitting their own countries, has to be a positive signal. Pearson confirmed to me that people in the sunshine state of Florida, where she lives, had become more aware of the importance of melting ice caps with increasing floods and storms.

As Levermann says, Antarctica and Greenland have a huge potential to raise sea level further than previously anticipated. He was lead author on the IPCC report chapter on sea level rise. The latest IPCC report factored in some of the likely impacts from melting ice in these regions for the first time. Of course the latest research was not yet included. For the 21^st century forecast, this will not make a lot of difference, says Levermann. But the fact that this irreversible Antarctic melt is now underway will make a big difference to coming generations.

There are those who dispute whether the warming of the ocean, which is causing the Antarctic melt (unlike the surface melt on Greenland) is man-made. Levermann does not rule out natural variation as a possible influence. But ultimately, he says, that is irrelevant. Greenhouse gas emissions and so human interference are warming the planet, and any further warming, whatever the cause, will speed up ice melt. So cutting emissions is the way to slow it down and, Pearson adds, gives people time to adapt to rising seas.

The combination of models based on the principles of physics, using a higher resolution than ever before, and evidence from ice cores showing what happened in the past, make for a high degree of certainty about these ice developments, says Levermann.

“The level of warming will determine the rate with which we discharge West Antarctica, and we can still prevent the tipping of East Antarctica”, the cryosphere experts told us here in Bonn.

That is a huge responsibility. Here’s hoping the message will make it into the hearts and minds of those negotiating the future of the earth’s climate and the governments they represent.