22 Apr, 2016
Is the warming Arctic incubating a methane monster that could unleash mass extinction on Earth?
By Ronald L. Shimek, Ph.D.
Excerpted in Full from CORAL Magazine, Volume 13, Number 3
May/June 2016 | Introductory Comments
I set out with an assignment to explore and report on predictions of coral reef extinctions in the coming decades. What I found was even worse, the most disturbing science story of my lifetime…and yours, if it happens to come true.
In the summer of 2014, a series of curious events occurred in the far north of Siberia’s Yamal Peninsula, an expanse of remote tundra jutting into the Kara Sea and totally off the radar of most news gatherers. Yes, the remarkably well-preserved remains of a 37,000-year-old female woolly mammoth calf named Lyuba had been found here in 2007, but the more recent news was largely ignored outside of the immediate region, a vast wilderness of treeless permafrost sparsely inhabited by the indigenous Nenets people and their herds of reindeer. By the following summer, however, stories about the appearance of several huge blowholes–or craters, depending upon who was describing them–were being told and discussed by a handful of science observers, mostly on the fringes of mainstream media. Once they were brought to my attention, these sketchy articles about peculiar happenings in the Arctic Circle began to fit into some deeply troubling scenarios and sleepless nights.
At first, I found these events interesting for a number of reasons, but mostly because I have long been fascinated by Russia, particularly Siberia and its animals and indigenous peoples. Some of this interest undoubtedly originated from my early university classes and the people associated with them, as well as a stint teaching biology at the University of Alaska, Anchorage. Ironically, I now had an assignment to look into predictions being made about the demise of tropical coral reefs in the latter half of this century. Strange nature stories from the Arctic Circle initially appeared to be a mere distraction, but the closer I looked, the more links to the future of life well outside the polar regions emerged.
Northern Siberia is an area of continuous permafrost and tundra, far above the Arctic Circle and a significantly less enjoyable place in midwinter than my home state of Montana or, actually, just about anywhere else. The Yamal Peninsula, on the shore of the Arctic Ocean, is the site of one portion of the largest natural gas field in the world. As a result, stories about the peninsula sporadically make it into the news. Most concern the intense off-and-on interest in Russian gas exploration and extraction. Bordered by the Kara Sea to the west and the Gulf of Ob to the east, Yamal is said to mean “world’s end” in the language of the Nenets. I wondered what the Nenets reindeer herders were thinking when they named the place, and I would have occasion to ponder this again as my research continued.
In the early summer of 2014, though, the Yamal Peninsula made the headlines for much more than Russian gas exploration. All of a sudden, it was said, a huge new crater had been found in the surface of the peninsula. That summer at least two more craters appeared, one in the Taz District south of the Arctic Circle and one on the Taymyr Peninsula in far northern Siberia. By the end of the summer, the actual number of craters or “blowholes” found was uncertain. It appears that some of the sources simply recycled older reports, but possibly as many as five large craters and a large number of smaller ones were created.
Left: A 2014 tundra blowhole; this particular blowhole was reported to have had a diameter ranging from about 100 feet (30 m) to 300 feet (100 m). A few reports stated the hole was about as deep as it was wide. For all blowholes examined, melt water started to fill the holes immediately, and eventually resulted in a circular lake.
Two years after the event, however, an online search reveals only one peer-reviewed journal article mentioning these craters, and that was in passing. No verifiable latitude and longitude coordinates have yet to be reported. Were these craters not significant enough for the attention of academia?
Later reports claimed that local reindeer herders saw a flash and some flames followed by smoke, and then heard what sounded like an explosion somewhere over the horizon, in the direction of one of the blow holes. Because of their shape and other characteristics, Russian scientists who came to examine them said that these craters were not the result of meteorite impacts. (They are, in crime-scene parlance, “exit wounds.”) It rapidly became apparent, at least to some observers, that they must be the result of the violent liberation of gas, specifically methane gas, in the permafrost.
The favored explanation for the craters was that this “mobilization of gas” probably had been going on for some time, the duration of which is uncertain. However, the gas couldn’t make its way up through the tundra and got trapped under a “lid” of permafrost, which normally has the consistency, flexibility, and porosity of concrete. (There are warning signs of gas accumulating. Mounds of cracked earth deforming the permafrost surface are often referred to as “pingos.”) Eventually, a large enough volume of gas built up to create a pressurized gas cavity that resulted in the methane spontaneously combusting; under some conditions, methane is highly unstable and will do this. In turn, this would result in a rather impressive and violent eruption, which fits the herders’ observations—or, in other areas, perhaps the permafrost simply gave way and the cork blew out of the bottle. The two, three, or four blow holes that were created measured up to about 265 feet (80 m) in diameter and depth—the biggest was about the width of an official soccer field and deep enough to swallow a 25-story building. Soon, smaller blow holes appeared surrounding the initial one(s). In a relatively short time, the bottoms of the blow holes filled with water and the sides collapsed. Tests of some craters have found high concentrations of methane gas at the bottoms of the blow holes.
The warming Arctic
Surprisingly, these methane-related happenings in the far, cold north in recent years are becoming a matter of record and have been traced to the thermal effects of a warming climate. Although we tend to think of global climate change as being manifested in such events as abnormally powerful storms, rising sea levels, and bleaching coral reefs in the tropics, the most severe effects have occurred in the colder northern parts of the world, particularly in those areas north of 60 degrees latitude, or north Anchorage. In fact, the effects of global climate change have been most extreme above and near the Arctic Circle. Some monthly temperatures are now as many as 7 to 11°F (4–6°C) above the 1980–2000 temperature averages. Although the average monthly rise in temperature is less than that, not only are the temperatures increasing up north, but the rates of the increases are accelerating as well.
Several factors contribute to the changes in the Arctic. The initial changes that got the snowball melting may have been a result of the earth’s axial inclination. Through much of the year, the ground and ocean surfaces in the northern boreal and Arctic regions are covered with snow, which reflects most of the light and heat falling on it. Many of the Arctic areas are very arid—they are almost deserts, getting very little precipitation throughout the year, most of which falls as snow. Consequently, in spring, it takes very little sunshine and heat to melt away the meager winter snowfall, exposing darker surfaces. After the snow melts, the darker tundra and boreal forest absorb a lot of heat energy.
The heat accumulation is rapid and strong, due to daylight that is present almost entirely or entirely throughout the day. Although that light is fainter than the light in the temperate or tropic regions, the number of hours during which light impinges ramps up the effective cumulative sunlight energy tremendously. As the land warms, the Arctic Ocean ice cover melts. In the first few years of changing climatic conditions, Arctic heating melted parts of the oceanic ice cap, but this simply resulted in a thinner ice cap. However, as time passed and the climate kept getting warmer, the ice over the ocean begin to melt away entirely in many places, exposing the open ocean a bit more each year.
Positive feedback loops
Once this started, the dark ocean itself began to absorb heat and help to melt the remaining ice. This resulted in one of many positive feedback loops, otherwise known as self-reinforcing cycles, in which a cycle’s result causes the cycle to intensify. In this case, as the temperatures warm, the white reflective ice and snow cover melts, increasing the area of dark ocean surface that absorbs more sunlight and heat. In turn, more ice melts, resulting in more areas of dark ocean surface…and on and on, only stopping with the onset of winter each year.
In the past couple of years, several important side effects of the warming of the Arctic water and land surface have manifested in the temperate zones where many of us live. For example, as the Arctic becomes warmer, the temperature difference between the polar and temperate jet streams starts to disappear. As that difference becomes less and less, the polar jet stream, no longer stabilized by the temperature differential between it and its southern neighbor, starts to “wobble” in its position, and may even fragment. The polar jet stream fragmented early in the 2013–2014 winter, causing a portion of the deflected jet stream to move far southward and, in the process, become oriented almost along a north-to-south axis, where it remained for several months in the winter and spring.
This fragmentation and dislocation of the polar jet stream had far-reaching consequences in 2015. It moved to the south and blocked the temperate jet stream that normally blows across the northern U.S., forcing it far to the south and allowing the “so-called” polar vortex to move southward, to the east of the displaced polar jet stream, bringing the record-cold winter weather of 2014–2015 to the American midwestern and eastern states while providing the northwestern states and western Canada with a mild winter. Additionally, by blocking eastward-moving moist air and mid-latitude Pacific storms from making landfall in California, it also greatly exacerbated that state’s nasty drought. Tropical air blowing east across the middle to northern Pacific Ocean was shunted almost directly northward, giving central and interior Alaska record-high temperatures in the spring of 2015; these temperatures, in the 80–90ºF (26.6–32.2ºC) range, were hitherto unknown in that region. Of course, this further warmed the already overheated Arctic, melting off the meager snowfall and drying out the taiga or boreal forest and tundra biomes, paving the way for the huge summer wildfires of 2015. All of these situations could repeat in future years. What happens in the polar circle does not necessarily stay in the polar circle.
Ice that burns
While weather events in populated countries are clearly observable and undeniable, an unseen effect of earth’s warming has been the mobilization of immense quantities of methane, aka “natural gas” (CH4). In Russia and the lands of the far north, this common gas occurs as methane ices, also known as methane hydrates, methyl clathrates, or simply clathrates, buried in the permafrost and deep ocean bottoms.
There are a couple of different clathrates, and they differ primarily in their carbon source. Generally, to the naked eye, methane ices, or methyl clathrates, look like familiar H2O ice, but that appearance is misleading. Instead, they are a combination of methane and water that together, under the right temperature and pressure, form three-dimensional microscopic, crystalline lattices or “cages” of water ice surrounding a large amount of entrapped methane gas. If a piece of clathrate “ice” is removed from water and allowed to start thawing, a burning match applied to the top will cause the released methane to burn with a pretty blue flame, while cold and, generally, fresh water drips from the bottom. One liter of clathrate ice may contain as much as 164 liters of compressed, trapped methane gas.
Slightly lighter than water, clathrates will float if dislodged from ocean or lake bottoms. Huge deposits of such materials, which were essentially unknown until about 20 years ago, have been found almost everywhere on the world’s ocean bottoms, where the appropriate depths of 656 to 1640 feet (200–500 m) provide the pressure and ambient cold temperatures (about 35.6ºF/2°C) necessary to stabilize them. As long as those moderately deep waters remain cool to cold, the clathrates won’t melt and the methane won’t be going anywhere.
The Arctic Ocean is unusual in that it also contains many areas with huge amounts of methane ice in much shallower water, only 65 to 100 feet (20–30 m) deep. For millions of years, the extreme cold of the Arctic has kept them stable. Unfortunately, in recent years, some parts of these shallow waters, mostly over the East Siberian Arctic Shelf, have suddenly become warm enough to melt at least some clathrates, which are already starting to release large amounts of methane.
Clathrates are also found deep in ice cores taken from the Antarctic and deep in Russia’s Lake Baikal; other large deposits of clathrates are frozen in permafrost, “permanently” (we once thought) frozen soil and rock. In some regions the permafrost, frozen to depths in excess of 1,000 feet (300 m), contains unbelievably immense numbers of methane ices, as well as frozen anaerobic sediments. If the permafrost thaws, the clathrates will decompose and release methane gas and the anaerobic sediment bacteria will become active, also releasing methane as a byproduct of their metabolism.
So, what’s the big deal with methane? We know that cows belch it and that, as compressed or liquefied natural gas, it is used daily for heat and cooking in millions of homes and businesses. It is an everyday fuel of modern life and the cleanest-burning hydrocarbon.
As it turns out, methane—CH4— is also a very potent greenhouse gas, efficiently retaining thermal energy in its molecules (see page 42). Liberated into the atmosphere, depending on various conditions, a methane molecule might be up to 100 times more effective as a greenhouse gas than a carbon dioxide (CO2) molecule would be under similar circumstances. If carbon dioxide is the familiar foe in most descriptions of global warming, methane is the lesser-known but more lethal archvillain, colorless and odorless at room temperature but in its different forms capable of retaining tremendous amounts of thermal energy—heat. Fortunately, atmospheric methane breaks down over time, producing carbon dioxide and water vapor. While both of these are also greenhouse gases, they trap heat significantly less efficiently than does methane.
Once released into the air, methane remains in the atmosphere, holding heat close to Earth rather than letting it escape up and out into space, for as long as 20 to 30 years or more. Presently there are, worldwide, an estimated 5 gigatons (giga = billion) of atmospheric methane, and the concentration in Earth’s atmosphere has increased 150 percent since 1750. Climate scientists already consider methane getting into the atmosphere a very serious concern.
A dragon awakens
The Arctic, as an ecosystem, is dying and decomposing; it is now warmer than it has been for the last 110,000 years. The changes documented there over the last decade are considered irreversible by most experts on Arctic ecosystems. The total amount of potentially releasable carbon stored as methane clathrate beneath the Arctic is greater than the entire amount of carbon found in all global coal reserves. Because the Arctic is heating up faster than any other region, the stability of the methane hydrate and permafrost methane deposits has recently begun to draw the attention of some scientists.
Dr. Natalia E. Shakhova is a Russian oceanographer and geologist who has been studying the permafrost methane distribution throughout the offshore region of the Laptev Sea known as the Eastern Siberian Arctic Shelf (or ESAS in scientific circles) and the adjacent onshore areas. A professor and researcher at the University of Alaska, Fairbanks, she estimates the clathrate deposits in the ESAS to be between hundreds and thousands of gigatons. This is not easy to visualize, but the total mass of carbon in living plants and animals on Earth has been estimated at 500 gigatons, making these buried deposits of solidified methane unimaginably huge in the true sense of the word. Some observers have dubbed the collective, buried power of these deposits the “Methane Dragon.”
In 2010, Shakhova and her co-workers estimated that a catastrophic methane release in excess of 50 gigatons (a minuscule percentage of what is in that area) is possible at any time. She said, and continues to assert, that such a catastrophic release could take place over a period of one to ten years. The fear is not the potential explosive effect—terrifying caribou in the wild, barren north—but rather the massive infusion of enormous clouds of potent greenhouse gas into Earth’s atmosphere. As a result of her work, the question that needs to be asked is this: “Are her estimates of catastrophic release reasonable and possible? And, if they are, what difference would that make?”
Bubble, bubble, toil and trouble…
Around the turn into this century, Dr. Shakhova and her colleagues and coworkers, who had been examining the conditions in the ESAS with regard to its methane clathrate deposits and warming, began to publish the results of their research. Because of the difficulty of doing long-term research in the Arctic, few other people have done any research on methane in that region, even though it obviously contains a great amount of the gas. Still, Shakhova is not alone.
In the summer of 2014, a joint Swedish-Russian-American international expedition–known as SWERUS-3 and based on the Swedish icebreaker Oden–was sampling methane emissions, among many other things, in the Laptev Sea off the northern Siberian coast. One of the participants, Dr. Igor Semiletov, who is Shakhova’s research partner and spouse, said later that in previous years they had found methane bubble plumes tens of meters in diameter; in 2014, however, the plumes were over 3,280 feet (1 km) in diameter. Additionally, the plumes were very common—thousands of them were found extending over a larger area than the expedition was able to survey. It should be noted that 2014 was a particularly warm year in the ESAS region, as were the two preceding years. No data have yet been published detailing conditions in the summer of 2015. This may be due to one of two factors: first, the summer of 2015 was cooler and this resulted in less methane production; and second, for any number of potential reasons, nobody was looking at this problem last summer—probably because research funds are in very short supply in both Russia and North America.
In a 2010 publication, Shakhova, Semiletov, and their co-workers estimated the accumulated methane potential for the Eastern Siberian Arctic Shelf alone to be approximately 2,200 gigatons, as follows:
• 500 Gt (gigatons) in permafrost;
• 1000 Gt in hydrate deposits;
• 700 Gt as free gas beneath the gas hydrate stability zone.
At the same time, they estimated that methane emissions in this region already exceeded 8 million tons annually. Remember, only 5 Gt are found in the Earth’s atmosphere now, in early 2016, and the planet is already warming at an alarming rate. With the 2014 observations, it certainly appears that the champagne bottle has been uncorked in this area and given a good shake, so emissions are at least continuous. Ominously, no detailed surveys of the extent of clathrate distributions in other Arctic regions have been attempted, so the global total is unknown.
Summer up North
Rising summer temperatures across the entire Arctic are helping to drive the earlier melting of the Arctic Ocean sea ice each summer. As a result, the ocean heats up a little bit more each year. When it refreezes each winter, the depth and amount of the sea ice formed is less than the prior years. The rise in air temperature, along with the increasing percentage of ice-free ocean water each summer, helps drive the continuing increase in ocean temperature and, as a result, not only are the temperatures of everything in the region increasing, but the rate of those increases appear to be increasing. This is either a good thing or a vicious circle, depending which side of the fence you are standing on.
Throughout the boreal regions—in both the north and the south, but mostly in the north because of the larger land mass and shallower marine waters—air temperatures at various places and various times are now reaching 5.4 to 18°F (3–10°C) above historical averages. In print articles and numerous online opinion postings, a range of authors are expressing the fear that the rate of the melting Siberian permafrost or heating ocean might rapidly accelerate until there is a sudden release of vast amounts of trapped methane into the atmosphere, leading to rapid, severe, and irreversible climate change.
The methane dragon stirs
The plumes that the 2014 SWERUS-3 expedition saw were definitely injecting methane directly into the atmosphere. Stockholm University’s Örjan Gustafsson, the expedition’s chief scientist, maintained a blog that included the following post: “Our first observations of elevated methane levels, about ten times higher than in background seawater, were documented…we discovered over 100 new methane seep sites… The weather Gods are still on our side as we steam through a now ice-free Laptev Sea…” The present average atmospheric methane concentration over most of the world is about about 1.28 parts per million (ppm). Until fairly recently, that was close to the concentration over the Laptev Sea and the ESAS as well. However, on August 3, 2014, the atmospheric methane concentration over one plume in the ESAS field was recorded at 318 ppm (2.5 times higher than expected).
Apparently, as a result of reading Gustafsson’s post, Dr. Jason Box—a well-known and highly respected climatologist at the Byrd Polar and Climate Research Center at Ohio State University, who is also regarded as a tad outspoken—responded by tweeting from Greenland, where he was working: “If even a small fraction of Arctic sea floor carbon is released to the atmosphere, we’re f—d.”
In the worst of all possible situations, the gas from many offshore plumes in one area combines with the methane released from under the nearby onshore terrestrial permafrost, creating areas of localized rapidly rising temperatures. This causes a positive feedback loop in the system and increases all releases in this area, which would expand in size both longitudinally and latitudinally. Within a short time, methane levels elsewhere in the region would start to increase, as would the size of the region affected.
At the present time, the relative state of Arctic methane hydrate deposits in the context of increasing Arctic seawater temperatures, and the concomitant impact resulting in the loss of Arctic Ocean sea ice, is really unknown.
Tipping point for runaway warming
The specter of Shakhova’s envisioned worst-case, 50-gigaton release hinges on many variables and unknowns. Estimates of just what is the tipping point, or better, the “trigger point,” have come from many different groups, but the overwhelming opinion is that this sort of colossal clathrate release would lead to a methane-induced climate cataclysm.
When and how things might unfold is profoundly uncertain, but the trigger point for the short-term catastrophic methane release postulated by Dr. Shakhova could be a temperature rise as low as an additional 1.5°C or as high as an additional 10°C. These are not the rantings of fearmongers, but scenarios described by respected Arctic oceanographers. The 50-gigaton decadal methane pulse scenario posited by Shakhova, Semiletov, and Alekseev, who are probably the leading experts on Arctic methane and methane ices, is considered plausible by scientists at the UK Meteorology Office, as well as multiple scientific reviews, including one written by more than 20 Arctic specialists. Current Arctic atmospheric methane concentrations are unprecedented, but the best minds believe that if 50 Gt were added to the atmosphere, conditions would become very bad, very fast. It would be, some experts fear, the beginning of “runaway global warming” that humans would be powerless to stop.
Given an effective meltdown of methane clathrates in the Arctic, climate expert Dr. Malcolm Light has estimated global temperatures of around 50°C above averages between the years 2040 and 2050. In summer, if the normal average had been 30°C (for example, where I live in Montana), the post-methane belch temperature would rise to 80°C or 176°F.
While the timing is unclear, the consequences can be predicted with some certainty. They include:
• Complete melting of polar ice caps; global flooding
• Disruption of global ocean currents and gyres; demise of oceanic fisheries
• Crop and food production failures
• Spread of disease and parasites
• Collapse of power grids and transportation systems
• Mass human mortality in heat and cold waves
• Catastrophic breakdowns in political, economic, and societal stability.
There is no easy way to write these words: Should such an event occur, it is certain that the coral reefs I set out to research would have no chance of survival. More to the point, most of us would perish.
Denial: Meet de Permian
Confronted with the worst possible news, a common human response is denial. I am acutely aware that people reading this are already saying that the science is faulty or, most likely, the scientist at the core of this scenario is dead wrong.
Not surprisingly, as soon as Dr. Natalia Shakhova’s group began publishing their findings a few years ago, it became apparent almost immediately that other scientists were split over the validity of their research. Although many contradictory arguments were posted in the blogosphere and in various other venues, no actual research results contradicting the results or conclusions of Shakhova’s group have been published.
Quite a number of researchers have been working with Dr. Shakhova and other members of her team, and as far as I can determine, all of them agree with her. It is notable that essentially all the people who have been doing active research on Arctic methane or clathrates support Shakhova and her colleagues.
In fact, a catastrophic series of eerily similar events has already happened here on Earth, and it probably started in the same desolate vastness of Siberia. Two hundred and fifty million years ago, an estimated 95 percent of all life forms on the planet were destroyed when the globe apparently became lethally hot in a relatively short period of time. This event is called the Permian Extinction, and some of the brightest scientists on Earth are convinced that a primary suspect was a colorless, odorless, smothering greenhouse gas sometimes called dragon’s breath—methane.
In second part of this article in the next issue of CORAL, Dr. Shimek will look at the disquieting similarities between Earth leading up to the Permian Extinction 250 million years ago and global conditions today, with expert predictions of what may be in store for the planet in coming decades and what, if anything, might be done to change course.
ABOUT THE AUTHOR
Ronald L. Shimek, Ph.D., is a marine zoologist and former biology professor who has authored numerous peer reviewed papers and hundreds of popular science articles. He is the former chair of the Biology Department at the University of Alaska, Anchorage and assistant director of the Bamfield Marine Science Centre on Vancouver Island, Canada. He is a CORAL Magazine senior editor and lives with his wife, Roxie Friedrickson, in Wilsall, Montana.
Copyright © 2016 by Ronald L. Shimek, Ph.D. and CORAL Magazine
Excerpted in Full from CORAL Magazine, Volume 13, Number 3
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Dr. Natalia Shakhova: Methane Hydrates – Extended Interview Extracts With Natalia Shakhova
Credit: Nick Breeze | YouTube
SWERUS: Swedish – Russian – US Arctic Ocean Investigation of Climate-Cryosphere-Carbon Interactions – The SWERUS-C3 Program
About the author
I am a marine biologist/invertebrate zoologist who got captivated by – or sucked into – the reef aquarium hobby late in the last millennium, I have written widely in the hobby press and elsewhere, mostly about invertebrates (in the context of the hobby, anything but fishes) and how to keep them alive. I reside in Wilsall, Montana, about as far from the ocean as one can get and still live in the contiguous 48 states, go figure… What can I say, it is home. :-)