Arctic methane: time bomb or “boogeyman”?

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.