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Arctic Methane Alert — Ramp-Up at Numerous Reporting Stations Shows Signature of an Amplifying Feedback

Over the past few months, reporting stations around the Arctic have shown a ramping rate of atmospheric methane accumulation. The curves in the graphs are steepening, hinting at a growing release of methane from a warming Arctic environment.

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Alert, Canada Methane June 1 2015

(Alert, Canada methane graph shows atmospheric methane increases in the range of 20 parts per billion in just one year. This rate of increase is 2-3 times the global average for the past five years. A skyrocketing rate of increase. Image source: NOAA ESRL.)

A Massive Thawing Carbon Store in the Far North

The science is pretty settled. There’s a massive store of ancient carbon now thawing in the Arctic.

In the land-based permafrost alone, this store is in the range of 1.3 billion tons — or nearly double the volume in the atmosphere right now. Arctic Ocean methane hydrates in the East Siberian Arctic Shelf add another 500 billion tons. A rather vulnerable store that does not include hundreds of billions of additional tons of carbon in the deeper methane hydrates around the Arctic in places like the Gakkel Ridge, in the Deep Waters off Svalbard, or in the Nares Strait. Massive carbon stores of high global warming potential gas locked in frozen ground or in ice structure upon or beneath the sea bed.

But now human beings — through fossil fuel emissions — are dumping heat trapping gasses into the atmosphere at an unprecedented rate. These gasses are most efficient at trapping heat in the colder, darker regions of the world. And, due to a combination of massive Northern Hemisphere burning, and release from the Arctic carbon stores themselves, the highest concentrations of greenhouse gasses can be found exactly where they are needed least — in the world’s far northern zones .

Arctic Overburden May 29

(The Arctic consistently shows an overburden of methane gas — both at the ground and upper levels of the atmosphere as seen in this METOP graphic from May 29. Such an overburden is but one of many proxy indicators of a ramping rate of release.)

This accumulation and overburden of heat trapping gasses is causing the Arctic to rapidly warm. A rate of warming (now at half a degree Celsius per decade for most regions) that is providing a heat forcing pushing the ancient carbon stores to release. A heat forcing now greater than at any time in the past 150,000 years (and likely more due to the fact that the Eemian Arctic was rather cool overall). A heat forcing rapidly ramping toward at least a range not seen since major glaciation began in the Northern Hemisphere 2-3 million years ago.

The problem for science, then, is two-fold. First, as oceans warm and permafrost thaws, how rapidly will the carbon stores release? And, second, how much of that carbon store will release as CO2, and how much will release as methane? From the point of view of global warming, both CO2 and Methane emissions feedback is a bad outcome of human-forced warming. But methane, which has a global warming potential of between 25 and 120 times CO2 over human-relevant timescales, has a real potential to make an already bad human heating of the Earth System much, much worse.

Methane Bubbles in Thermokarst Lake

(Image source via Science 2.0.)

Most Arctic Reporting Stations Show Rapid Ramping of Methane Gas Accumulation

For this reason, monitoring methane gas accumulation in the Arctic is a key feature of global climate change risk analysis. If the Arctic shows a spiking rate of methane accumulation, then the carbon stores are more susceptible to rapid release of potent heat trapping gasses and we are facing a high urgency situation in need of rapid global response.

Over the past decade, the Arctic has shown numerous isolated or regional spikes to very high methane levels with an overall continued accumulation within the atmosphere. The Arctic also displayed a major overburden of both methane and CO2 — proxy indications of local carbon store feedbacks already ongoing on a minor-to-moderate scale. This combination of overburden and spikes provided a troubling context, especially when adding in observations of methane store release through thermokarst lakes and, later, blow-holes in locations like Yamal, Russia. But up until last year, we had not seen a third, and more troubling, indicator — the ramping rates of atmospheric methane accumulation that would be an early warning that the Arctic carbon store was indeed starting to blow its stack.

But now, that signal is starting to show up at almost every Arctic reporting station. A steepening curve in the Arctic atmospheric methane graphs. A signal we really, really don’t want to be bearing witness to:

Barrow Methane June 1 2015Alert, Canada Methane June 1 2015

Summit Greenland Methane June 1 2015Svalbard Methane June 1 2015

(Major reporting stations from Svalbard to Barrow show a ramping atmospheric methane accumulation [Click on individual images to expand]. It’s a signal that is yet one more indicator of an amplifying methane and greenhouse gas feedback to human warming now going on in the Arctic. Images provided by NOAA ESRL.)

Now, it seems, at the very least, we are witnessing a spike in Arctic atmospheric methane accumulation. Let’s hope it’s just a spike and not the start of another ugly exponential curve associated with human-forced atmospheric warming. But if we are witnessing the early ramp of such a curve, we should be clear that we are now in the context of a worst-case climate change scenario.

Hot-Button Topic of Critical Importance

For years, conjecture over the possible rate of Arctic Methane release in a human-warmed Arctic has been the source of extreme scientific and media-based controversy. Major oil companies have used the issue as an excuse to continue fossil fuel burning (irresponsibly spreading the meme — ‘we’re screwed, so we may as well just keep burning anyway’). Major climate scientists and related media outlets have sought to tamp down concern over large-scale methane release by issuing articles with titles like ‘Apocalypse Not’ with many generally insisting that there is practically zero likelihood of a large-scale methane release or major amplifying feedback. Meanwhile, the observational studies have continued to indicate risk of at least moderate and possibly strong methane feedback in an age of rapid human heating of the Arctic environment (studies like this recent paper which observed microbes tripling the rate of methane gas release in thermokarst lakes as a response to Arctic temperature increase.) Finally, a group of very concerned observational scientists like Natalia Shakhova, Igor Simeletov and Peter Wadhams have warned that a large-scale methane release is likely imminent and begs a major response from the global community (sadly, many of these proposed responses have come in the form of geo-engineering — methods which are far less likely to succeed and far more likely to generate unforeseen and highly disruptive consequences than simple cessation of human fossil fuel emission and a transition to carbon-negative civilizations).

Mauna Loa Methane June 1 2015

(Mauna Loa methane measure through June 1, 2015 shows that lower Latitude regions are also starting to follow a ramping rate of increase. Image source: NOAA ESRL.)

All this controversy aside, what we observe now is the following:

  1. Arctic methane and CO2 overburden — proxy indication of environmental release.
  2. Increasing rates of release, indications of increasing release, or possibly increasing release from single sources such as thermokarst lakes, peat bogs, wildfires, and sea bed hydrates and submerged tundra.
  3. A multiplication of observed or discovered methane release sources — thermokarst lakes, methane blow holes, wildfires etc.
  4. A ramping rate of atmospheric methane accumulation at reporting stations throughout the Arctic (most but not all stations).
  5. A ramping rate of atmospheric methane accumulation from global proxy monitors like Mauna Loa and in the global atmospheric average.

Together, these observations represent a troubling trend that, should it continue, will be proceeding along or near a worst-case climate sensitivity track. As such, these new ramping rates of increase in Arctic atmospheric monitors are a very unfortunate indicator.

Links:

NOAA ESRL

NOAA OSPO

Arctic Methane Skyrocketing

Microbes in Thermokarst Lakes Increase Methane Generation with Warming

Arctic Sea Ice Melt, Methane Release Shows Amplifying Feedback to Human-Caused Climate Change

 

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Like a Volcano Slowly Awakening at the Top of our Earth: From Baffin Bay to the Laptev Sea, Arctic Methane Monster Releases Troubling Outbursts

The most dangerous of volcanoes have a number of identifiable behaviors.

They tend to lay dormant for hundreds, thousands, or tens of thousands of years. Then, slowly, as heat and pressure beneath the Earth builds, they begin to awaken. First they tremble a bit. Then they emit a growing volume of noxious gas. Then, they begin a series of mini-outbursts in an ever more violent build-up to an explosive and destructive grand eruption.

The lost residents of Pompeii, were they here today, could tell us what such an event is like.

Now consider that a volcano-like thing also exists beneath the world’s frozen oceans and lands near the roof of our world. A thing that probably hasn’t erupted in over 45 million years. A thing that has had this immense period of time in which to build up an enormous highly toxic and explosive reserve of frozen and sequestered methane. A thing that is at least as large as the boundary circumscribed by the Arctic Circle. A vast and extraordinarily dangerous monster of a thing. A kind of climate super-volcano.

AIRS_Methane

(Initial methane out-gassing shows a tell-tale methane overburden in the troposphere near Arctic ocean and tundra methane sources in 2011. Just one of many signs of what may be a very large, impending methane eruption. Image source: NASA/AIRS.)

For ever since the Earth began its long fall into cooling at the end of the Eocene, methane has been freezing at the bottom of the world’s oceans, sequestering in the frozen earth. As world land and ocean temperatures fell, the methane formed into clathrates or was bound up in organic permafrost and was, ever-after, locked away. There it lay patiently, waiting for the time when it would be, once again, disturbed by a return to warmth.

And that time of dangerous and explosive reawakening, increasingly, seems to be now.

Footprint of the Vast Volcanic Monster: Shallow Seas, Deep Seas, Permafrost

Of these volatile methane concentrations, some of the most prolific and the most vulnerable reside in the Arctic. Some, which lay sequestered within the shallow sea bed near the East Siberian Arctic Shelf, have been the subject of much controversy during recent years. Scientists like Natalia Shakhova and Peter Wadhams have issued repeated warnings that these methane stores could be vulnerable to a rapid release as sea ice retreats and waters warm. It is estimated that as much as 1400 gigatons of methane lay sequestered under Arctic submarine permafrost in the ESAS. A massive store that, if disturbed even in part, could provide an immense amplifying feedback to human-caused warming.

But the Arctic submarine permafrost isn’t the only zone in which large volumes of methane lay hidden. The Amundsen Basin, one of the deepest trenches in the Arctic Ocean, in the Laptev Sea is a known emitter of methane from sub-sea sources. A region near Svalbard both stores and emits large volumes of methane. And, recently, high rates of methane release have been observed near Baffin Bay. A complete catalog of these stores has not been adequately assessed. But, in combination, it is likely that they at least approach the total volume of stores in the vulnerable East Siberian Arctic Shelf (ESAS) zone.

Ominous Rumblings from the Rapidly Warming Deeps

These stores are deeper beneath the ocean surface and so are not generally thought to be as vulnerable as the shallow sea reserves in the ESAS. But this thinking may be in error as Arctic waters display a temperature inversion in which surface waters near the ice pack are colder than deeper waters far below.

In addition, wide zones of deep water in the Arctic have displayed rapid warming over the past few decades. As an example, bottom waters in the Greenland Sea, an area between the east coast of Greenland, Iceland and Svalbard, were shown in a September 2013 study to be warming 10 times faster than the rest of the world’s deep ocean system. According to the report:

Recent warming of the Greenland Sea Deep Water is about ten times higher than warming rates estimated for the global ocean. Scientists analyzed temperature data from 1950 to 2010 in the abyssal Greenland Sea, which is an ocean area located just to the south of the Arctic Ocean.

Deep Water Warming in Greenland Sea

(Deep Water Warming in the Greenland Sea since 1950. Image source: Science Daily. Image credit: Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research.)

In other regions of the Arctic and through the rest of the global ocean system rapid ocean bottom warming has also been observed. Recent studies by Kevin Trenberth have found that heat accumulation in the deep ocean, during recent years, has outpaced that of warming at or near the surface. And because this warming occurs adjacent to frozen methane stores on or beneath the sea floor, it is a very, very dangerous development.

To the point of an observed rapid warming of the deep ocean, it is important to note that there are a number of mechanisms that transport heat into the abyss worldwide. But in the Arctic, this transfer system is amplified and particularly intense. Fresh, cold surface waters tend to deflect warmer, saltier waters funneling in from more southerly latitudes toward the Arctic Ocean bottom. As glacial ice melts in Greenland, as storms within the Arctic intensify and become more prevalent, and as fresh water runoff from the continents surrounding the Arctic basin increases, fresh water content at the surface grows and widens, creating a kind of fresh water wedge that expands southward and deflects warmer, saltier water toward the ocean bottom.

And there, the warmer waters can go to work releasing the massive volumes of methane stored in frozen clathrates near the ocean floor.

Large Mid-February Methane Belch

Methane released from deep water clathrate stores has a long journey before it reaches the atmosphere. The methane passes through the water column, where a portion of it oxidizes into CO2. Microbes near the methane source and throughout the water column devour a portion of the methane as an energy source. But eventually, if the pulse is large enough, the methane finds its way to the surface and releases. Such outbursts are, likely, only a fraction of the initial bottom release. So a large expulsion into the atmosphere may well be a hint that something even more powerful and energetic is going on down below.

Over the past decade, deep water regions have shown at least as much atmospheric venting as the East Siberian Arctic Shelf. And this year has been no exception with troubling outbursts continuing in a zone from Baffin Bay to Svalbard to the Laptev Sea. These outbursts have, in part, contributed to increasing atmospheric methane concentrations at a rate of around 7 parts per billion each year since 2007 after an 8 year period during which global methane levels had plateaued at around 1790 parts per billion. By comparison, pre-industrial global methane levels were around 750 parts per billion during the 1880s. Today, they average around 1835 ppb (Mauna Loa). Should very large outbursts emerge, the rate of atmospheric methane increase would be expected to dramatically steepen. And though we haven’t yet seen these kinds of outbursts, more minor, but still large and concerning, continue to occur with troubling frequency.

This past week, according reports from Methane Tracker and Sam Carana, two particularly large and troubling ocean to atmosphere methane outbursts were observed in this region — one over the Laptev Sea and the other over Baffin Bay. The Baffin Bay outburst occurred in a zone where water depths ranged from 1,000 to 2,500 meters (middle to deep ocean) and the Laptev outburst likely occurred from the deep waters and precipitous slopes of the Amundsen Basin which plunges as deep as 4,400 meters (extraordinarily deep ocean) and extends almost directly under the North Pole.

Methane belch

(Methane belching from Laptev Sea and Baffin Bay on February 22nd with highest reading spiking to 2383 ppb, about 500 ppb above the global average. Image source: Methane Tracker and Sam Carana. Data source: composite methane data collection from SIO, NOAA ESRL, U.S. Navy, GEBCO. )

From these outbursts, 10,000 foot methane concentrations of 2383 ppb were observed. These readings are about 500 ppb higher than the global average and represent an extraordinary local spike for the Arctic.

The outbursts occurred in a region where the fresh water wedge was most recently active — areas where sea ice keeps expanding then melting and retreating as warmer, saltier waters encroach. Regions where the warmer water column would be continuously flushed toward ocean bottom zones containing methane hydrates.

If we were to continue with the volcano analogy, we could well consider the most recent Laptev and Baffin Bay outbursts to be a series of minor but intensifying eruptions. The most recent in a string of troubling and increasingly more volatile activity from the methane volcano rumbling at the top of our planet.

Links:

Deep Greenland Sea is Warming Faster than the World Ocean

Global Heating Accelerates, Deep Ocean Warming the Fastest, What Does it Mean for Methane Hydrates?

Methane Tracker

NOAA ESRL

Massive Methane Concentrations over Laptev Sea

2013 4th Hottest Year on Record, Deep Ocean Warming Fastest

Triggers to Release the Methane Monster, Deep Ocean Warming, Sea Ice Melt, Sea Level Rise and the Fresh Water Wedge

Methane Emissions From ESAS Occurring at Twice the Expected Rate

The Arctic Methane Monster Stirs

Beneath the Cracking, Melting Ice, The Arctic Methane Monster Continues it Ominous Rumblings

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