Advertisements

A Deadly Climb From Glaciation to Hothouse — Why the Permian-Triassic Extinction is Pertinent to Human Warming

In looking at the potential impacts of human caused climate change over the coming decades and centuries, scientists have often pointed toward more recent times such as the Eemian (the most recent warm interglacial in which global temperatures are similar to what they are now and where they are expected to be over the next 20 years), the Pliocene (2-3 million years ago and the most recent time in which CO2 levels were about equal to those of today), and the PETM (about 55 million years ago and the most recent period during which CO2 levels were above 600 ppm and in which there was very rapid warming, possibly due to methane hydrate release).

The PETM has been a period of very intense study for leading climatologists such as James Hansen who has warned of the potential for a mini-runaway warming event of this kind should humans continue along a business as usual path of fossil fuel burning through the 21rst Century. In particular interest in the PETM corollary scenario is both the amazing velocity of the initial human warming, with CO2 and greenhouse gas releases occurring at rates that are five (CO2) to 27 (methane) times faster than the PETM (Hat tip to Timothy Chase, Source: Skeptical Science). So rapid and powerful a rate of forcing puts at risk of greater release a number of very large global carbon deposits including the massive CO2 and carbon stocks stored in the world’s melting permafrost as well as the even larger stores of carbon locked in methane hydrates scattered across the world’s oceans. Hansen and other scientists have noted a potential for a 4-7 degree Celsius or greater warming by 2100 (at between 700 and 1000 ppm CO2) through a combination of human greenhouse gas emissions and Earth systems carbon emissions. Overall warming by 2300 from Earth Systems feedbacks, even if human emissions were to stop by 2100, is likely to be twice this level.

That such a massive warming would be catastrophic is a given. There is no evidence in the geological record for such a stunning pace of warming over so short a period. And the potential climate change impacts from such high levels of heating, alone, would be extraordinarily difficult for human civilizations and the innocent inhabitants of our living world to manage.

Late Permian Just Prior to De-glaciation

Late Permian Just Prior to De-glaciation at approx 260 million years ago.

(Image source: Ron Blakey, NAU Geology)

But this scientific scenario is based, in part, on knowledge gleaned by studying past geological periods such as the Eemian, Pliocene, and the PETM hyperthermal (other information is derived from the still-developing climate models of terrestrial, ocean, and Earth systems). And, in looking at each of these paleoclimate periods, we find that a single key factor is missing: they all occurred during periods in which Earth was either ice-free, or in which Earth was settling into its current period of glaciation. In the case of human-caused warming, the exact opposite process is ongoing. As during the great Permian Extinction event of around 250 million years ago, the Earth is rising out of a period of glaciation and into a potential human-caused hot-house.

No More Ice Ages and a Start Down the Path Toward De-glaciation

In the current period of human-caused warming we encounter the novel and relatively uncharted territory of an Earth System that is being forced to arise out of a 40 million year long period of glaciation. This period has been characterized, first, by the freezing of the vast land mass of Antarctica, then by the freezing of Greenland and, later, by long ice ages in which glaciers expanded from the poles to cover large areas of land and water. This latter ice age-interglacial period began about 800,000 years ago and has dominated until today.

Glaciation since PETM

(Image source: James Hansen)

With atmospheric CO2 levels now at 400 ppm and with humans continuing to emit high volumes of CO2 for at least the next two decades, we can officially declare the period of ice ages and interglacials at an end (or at least put on extended hold). For retaining even a very small portion of our current greenhouse gas emitting infrastructure or agriculture would be enough to stave off another ice age. Hansen notes:

Forces instigating ice ages, as we shall see, are so small and slow that a single chlorofluorocarbon factory would be more than sufficient to overcome any natural tendency toward an ice age. Ice sheets will not descend over North America and Europe as long as we are around to stop them.

Ice ages are now stopped in their tracks and current human levels of CO2 at 400 ppm are now sufficient to begin melting Greenland and West Antarctica. We can see this melt in yearly losses exceeding 500 gigatons of melt water and ice from Greenland and from Antarctic melt losses in the range of 300 gigatons per year or more. And with the increasing human heat forcing, these melt rates are on a very rapid incline. Greenland is showing a doubling in its melt rate every 5 years.

Yet even this, rapidly expanding, melt pace may seem slow if humans continue along their current path of greenhouse gas emissions growth. Last year, over 32 gigatons of CO2 were emitted into the atmosphere and the net human greenhouse gas emission was equivalent to more than 45 gigatons of CO2. At the current rate of emissions and emissions growth, we are now on track to hit between 500 and 600 parts per million of CO2 by the middle of this century. And this range of CO2 is enough or nearly enough to melt all the world’s ice, setting us on a path toward a place not seen in at least 40 million years. A path toward long-term temperatures in the range of 6 degrees Celsius hotter than the 1880s. If emissions continue until the end of this Century, the path is almost certainly toward that of a hyperthermal and one with unique consequences given the speed at which we approach it and the fact that we will send massive volumes of fresh meltwater into the oceans as we approach it.

The PETM and the Great Dying

And this is where we encounter a bit of a problem. Because the world is rapidly rising up out of a 40 million year long glacial period, it is bound to encounter changes not visible 40 million years ago as the Earth was steadily cooling down toward glaciation or even during the PETM as the Earth emerged from a lesser cool period and entered a hothouse state. In the case of the Permian and the current day, Instigating the loss of glaciers presents its own, rather unique, set of problems and difficulties.

In looking at the geological record, we find that the last major cold period with temperatures close to those of the recent ice ages (aside from a somewhat cool period during the late Jurassic and early Cretaceous) occurred during the late Carboniferous and the early to mid Permian period.

Past Hot and Cold Periods

Hot and cold periods during the last 500 million years (best proxy data used).

(Image source: Commons)

During the late Permian and early Triassic, however, very rapid and intense warming roughly equivalent to that of the Eocene of 55 million years ago occurred. Both events resulted in extinctions in the oceans and on land. Both events showed major temperature spikes toward the end that are theorized to be linked with large methane pulses and amplifying Earth Systems feedbacks. And both are typical to a mini runaway hyperthermal of the kind James Hansen warns is possible under a regime of human warming.

The primary differences between these two events is that, first, the Permian Triassic extinction event occurred after a long period of glaciation and, second, that the Permian extinction was the greatest mass extinction ever recorded in the geological past. What resulted killed off a devastating 96% of the species in the oceans and 80% of all species on land. It is for this reason that the Permian-Triassic boundary layer extinction is known as the great dying.

By contrast, the PETM resulted in a similar, but far less, extreme event. About 35-50% of the benthic forminifera of the deep ocean went extinct. Many other ocean species, especially those of the deep ocean, exhibited stress and losses. Life on land, especially among mammals, was pushed toward dwarfism to deal with the extreme high temperatures. But, overall, stresses to land and ocean animals was far, far less than that of the Permian extinction.

Putting a Lid on the Ocean — Glacial Melt’s Role in Enhancing Anoxia

At issue here is the likely anoxic ocean states resulting from major warming events. As the oceans are heated, they are able to hold less oxygen in solution. This steady depletion results in growing regions of anoxia and related algae blooms that can be very dangerous to marine and, in extreme cases, terrestrial organisms. Warmer, anoxic oceans are more likely to host blooms of deadly green and purple algae.

Troubling Green Algae Bloom North of Scandinavia.

Troubling Green Algae Bloom North of Scandinavia.

(Image source: NASA/Lance-Modis)

These primordial creatures once ruled the seas during the days of ancient Earth, before higher levels of oxygen were present. Now, a mixed, oxygen rich ocean keeps their development in check. But the warmer ocean during the time of the PETM is thought to have brought anoxic states back to the world’s deep oceans.

In short, ocean circulation is thought to have reversed. Heating at the tropics resulted in seas becoming saltier as waters there evaporated. These saltier waters grew dense and sank toward the ocean bottom drawing fresher, cooler water in from the poles. This type of ocean circulation is thought to have dominated for about 40,000 years during the PETM and contributed greatly to anoxic ocean states by concentrating warmer, anoxic water at the bottom of the world’s oceans.

During the Permian, anoxic ocean states were thought to be far, far more intense. Paleontological research conducted by Peter Ward found a massive series of three extinction events ranging over the course of about 165,000 years in which death began at the bottom of the Permian ocean and climbed toward the atmosphere.

It is thought by some scientists that rapid warming during the Permian enhanced both glacial melt even as it amped up the hydrological cycle to increase fresh water runoff from the continental land mass. The result was a much greater freshening of the ocean surface. Enhanced evaporation at the equator is thought to have driven a similar ocean circulation to that of the PETM in which hotter, saltier water sank to the ocean bottom. Glacial melt, in this case, greatly enhanced an ocean circulation change that was already leading to anoxic ocean states. The result was that ocean layers became even more stratified and less mobile further amplifying anoxia. In the case of the Permian, ocean anoxia eventually enveloped a majority of the worlds oceans, permeating all the way to the surface and eventually invading the atmosphere.

The Emergence of the Canfield Ocean

A stratified, anoxic ocean developed which started increasing mortality among deep water life forms first. As anoxia rose through the deep and mid levels of the ocean, death advanced up the water column as green and purple algae found sunlit regions and proliferated, adding hydrogen sulfide gas as a killing mechanism to ocean acidification and low ocean oxygen levels. Eventually, the hydrogen sulfide reached the surface waters at which point it began bubbling into the atmosphere. The anoxic ocean had fully transitioned to a primordial Canfield Ocean.

Hydrogen sulfide gas is directly toxic to both plants and animals alike and this great out-gassing likely resulted in the massive loss of land species. Ironically, high temperatures (on the order of 9-12 degrees C hotter than now) enhance the lethality of hydrogen sulfide gas. When the gas reaches the stratosphere, it depletes the ozone layer, causing even greater harm to land species. Fossil remains show evidence of genetic damage indicative of a depleted ozone layer and related Canfield Ocean state.

Human Warming is Much, Much Faster

It took about 20,000 years for the Earth to warm 6 degrees Celsius during the PETM. During the Permian, the final extinction and related warming events lasted about 165,000 years. In the case of the PETM, it is thought that volcanism in India stoked global warming until a rapid methane release over a 20,000 year spike period occurred. During the Permian, volcanism is thought to have burned through coal patches over a large region of Siberia, possibly eventually setting off similar very large methane pulses to those suspected to have occurred during the PETM.

In both cases, temperatures rose to between 9 and 12 degrees Celsius hotter than today. But, in the case of human warming, we have the potential to warm the Earth by as much as 7 degrees Celsius by the end of this century and, possibly, to Permian/PETM levels over the next 300 years. Such a rapid pace of warming holds no corollary in either the Permian, the PETM or during any other major warming event visible in the geological record of Earth’s past. So while we may look to the Permian for potential enhanced ocean circulation and anoxia impacts due to glacial melt and increasingly intense ocean stratification, we have no rational means by which to determine how far behind increasing temperatures and glacial melt such events may arise. In the case of the Permian, it took about 165,000 years for a Canfield Ocean to arise. But anoxic ocean states emerged and intensified as warming ramped up. So it is likely that ocean anoxia and stratification will become an increasing problem as the Earth rapidly warms due to human forcing. We can also expect glacial melt to amplify the problems caused by anoxia by increasing stratification and by pushing warm, oxygen-poor waters toward the ocean bottom where they have little opportunity to recharge oxygen stores. Lastly, in the worst case, we can look for Canfield Oceans as a potential tail-end risk for human warming, especially if global temperatures approach 9 to 12 degrees Celsius above the 1880s average and if very large fresh water pulses from glaciers shut down and reverse current ocean circulation.

Links:

Climate Model Links Past Extinction to Higher Global Temperatures

Changes in Permian Ocean Circulation, Anoxia in the Permian Ocean, and Changes in the Permian Carbon Cycle

Rapid and Synchronous Collapse of Marine Ecosystems During Permian Biotic Crisis

Carbon Isotope Anomaly in Conjunction with Biotic Crisis

Biogeochemical evidence for euxinic oceans and ecological disturbance presaging the end-Permian mass extinction event

Storms of My Grandchildren

Under a Green Sky

Advertisements

Arctic Heat: Wildfire Smoke Blankets Siberia, Alaska Shatters Temperature Records, Arctic Ocean Heat Sets off Large Algae Bloom

Siberian Wildfires July 31

Smoke from Siberian Wildfires now covers most of Arctic Russia. Image source: Lance-Modis.

There’s a lot of noise these days over the issue of global warming and human caused climate change. The static includes the intransigence of industry supported climate change deniers, a great confusion over climate context within some wings of the media, a number of increasingly personal attacks on the messengers — scientists, journalists, bloggers, and emerging threats experts — who communicate critical information related to climate change, and even a degree of professional disagreement within the sciences and among experts over key issues such as the potential rate of global methane release due to human warming.

(Read an excellent Guardian article about this debate here)

Despite all the vitriol, controversy and confusion, the signal coming from the Earth System couldn’t be clearer — the Arctic is showing every sign of rapid heat amplification and related emerging feedbacks and environmental changes.

The Arctic ring of fire

Over the continents circling the warming Arctic Ocean, a band from about 70 degrees north to about 55 degrees north, has increasingly erupted into heatwaves and massive wildfires. This year, huge fires blanketed both Canada and Russia, with a recent very large outbreak spreading over Siberia.

Over the past two weeks, numerous wildfires roared through Arctic tundra and boreal forests alike over a sprawling swath of northern Russia. These blazes rapidly multiplied to nearly 200 fires, covering most of Arctic Russia in a pallor of thick, soupy, smoke. The smog cloud blanketing Siberia now stretches nearly 3,000 miles in length and 1,500 miles in width, covering an immense slice of the Arctic and adjacent regions. The fires coincided with a large methane pulse that sent local readings to nearly 2,000 ppb, almost 200 ppb above the global average. Whether these higher methane levels were set off by a prolonged Arctic heatwave that has settled over Siberia since June or were tapped by the fires’ direct contact with thawing tundra remains unclear. But tundra melt and related carbon release, almost certainly set off by far above average temperatures for this Arctic region, clearly resulted in conditions that favored a heightened level of emission (You can track current global methane emissions through the excellent site: Methane Tracker.)

These massive blazes continued today with the most recent Modis shot showing a rash of red hotspots beneath a thickening ceiling of smoke:

Russia Fires July 31

(Image source: Lance-Modis)

Hat tip to the ever vigilant Colorado Bob for the new fire shot.

Arctic wildfires are an important and dangerous feedback to a warming polar climate. The fires produce soot that traps additional heat in the air while aloft and through reduction in the albedo of the surfaces it rains down upon. If the soot ends up on ice sheets, it can greatly amplify the summer sun, chewing large holes and accelerating melt (the Dark Snow Project is studying this highly worrisome dynamic). The fires also render carbon stocks locked in both the forest and the tundras through direct burning. As such, the fires result in a major extra CO2 emission source. The current fire in Siberia also appears to be exaggerating methane release from thawing tundra as large methane spikes appeared in the fire affected regions.

The result is that more heat is locked into an already vulnerable Arctic and global environment.

Alaska shatters temperature records

Meanwhile, across the Arctic, Fairbanks reported its 14th straight day of above 70 degree temperatures, shattering the previous record of 13 days running back in 2004. The Arctic location has also seen 80+ degree weather (Fahrenheit) for 29 days so far this summer and 85+ degree weather for 12 days this summer. The record for 80+ degree days is 30 during a summer and the previous record for 85 + degree days was 10 days. A ‘usual’ Alaskan summer only saw 11 80 degree days, with the current number for 2013 nearly tripling that mark.

So Fairbanks has shattered two summer high temperature duration records and is now closing in on a third. Since predictions call for high 70 to low 80 degree weather for at least the next few days, it appears likely that this final mark will fall as well. The Alaskan heat is expected to continue through at least this weekend after which temperatures are expected to fall into, the still above average, lower 70s.

Given these record hot conditions in Alaska, one has to wonder at the potential for fires to erupt in this region as well. An outbreak of large fires spread through the region in June. But compared to Canada and Russia, which have both seen major fire outbreaks, Alaska has been relatively quiet. Methane Tracker shows little in the way of 1950 ppb or higher readings over Alaska at the moment. But this is an uncertain indication to say the least.

The current Arctic Weather Map shows broad regions of warm to hot daytime conditions throughout much of the Arctic. Areas of highest temperatures are located in Alaska, Northwestern Canada, Siberia and Northern Europe. These Arctic heatwave conditions have persisted throughout the summer of 2013, drifting in a slow circle along with their related heat domes and high amplitude Jet Stream pulses.  So far, these conditions have shown little evidence of abating.

Alaska Canada Daytime Aug 1 Russia Europe Daytime August 1

The above images show respective daytime temperature forecasts provided by Arctic Weather Maps. Areas in red indicate temperatures ranging from 77 to 86 degrees. The first image shows daytime in Alaska and Canada for Thursday, August 1. The second image shows predicted daytime temperatures for Siberia and Europe for the same date.

Arctic Ocean heat anomaly soars

In addition to an immense rash of wildfires belching enormous plumes of smoke that now cover most of Northern Russia and record-smashing high temperature streaks in Alaska, we continue to see a rising heat temperature anomaly over a vast region of the Arctic Ocean. A broad stretch of sea area shows .5 to 1 degree Celsius above average sea surface temperatures. This region includes the Central Arctic Basin which has seen broad, anomalous areas of much thinner, more dispersed sea ice coverage. Isolated regions are showing temperatures in the range of 2 to 4 degrees Celsius warmer than average with the hottest region over the Barents and the Kara Seas near Norway and northern Russia.

sst.daily.anom

(Image source: NOAA)

The region where the highest heat anomaly measures have appeared also shows a very large green algae bloom. This oil slick like region is clearly visible in a freakish neon off-set to the typically dark Arctic waters. Higher ocean heat content and added nutrients increasingly fuel these kinds of blooms which can lead to fish kills and ocean anoxia in the regions affected. This particular bloom is very large, stretching about 700 miles in length and 200 miles in width along a region near the northern coast of Scandinavia.

Algae Bloom North of Scandinavia

Very large algae bloom north of Scandinavia. Image source Lance Modis.

As the oceans warm due to human caused climate forcing, there is increasing risk that large algae blooms and increasing regions of ocean anoxia will continue to spread and grow through the world ocean system. In the more extreme case, the current mixed ocean environment can turn into a dangerous stratified anoxic ocean environment. Past instances of such events occurred during the Paleocene and during ages prior. Oceans moving toward a more anoxic state put severe stress on numerous creatures inhabiting various ocean levels and is yet one more stress to add to heat-caused coral bleaching and ocean acidification due to increasing CO2 dissolution.

Ocean mixing is driven by the massive ocean heat and salt conveyors known as the thermohaline circulation. Slowing and changing circulation patterns can result in switches from a mixed, oxygenated ocean environment, to a stratified, anoxic state. Currently, a number of the major ocean conveyors, including the Gulf Stream and the warm water current near Antarctica, have slowed somewhat due to added fresh water melting as a result of human caused climate change.

Movement toward a more anoxic ocean state is an added stress on the world climate system and another of the myriad impacts set off by human warming. Though a complete switch from a mixed ocean to an anoxic ocean is still far off, it is an important long-term risk to consider. Perhaps one of the absolute worst effects of an unabated burning of fossil fuels and related carbon emissions by humans would be the emergence of a terrible primordial ocean state called a Canfield Ocean. But this is another, rather unsavory topic, likely worth exploring in another blog (nod to prokaryotes who has been fearfully hinting about risks associated with this particularly nasty climate mechanism on internet boards and in blogs and comments for years).

In the meantime, it’s worth considering the clear and visible effects of Arctic amplification currently in train: massive Siberian wildfires along with immense smoke plumes and troubling methane pulses, an ongoing Arctic heat wave that continues to break temperature records, and very high Arctic ocean temperature anomalies that are setting off massive algae blooms north of the Arctic circle.

Heat Dome Wildfires, Methane Pulse Expand, Blanketing Arctic Siberia in Cloud of Dense Smoke

Heat Dome Fires Siberia

An immense cloud of smoke covers Arctic Siberia. Image source: Lance-Modis.

 

Add sea ice near record low levels, a mangled, wavy jet stream, heat dome high pressure systems that increasingly emerge in a thickening atmosphere, a global warming induced increasing of the hydrological cycle and warmth-amplifying methane seeps from the tundra and what do you get? Summer Arctic heatwaves that persist over days and weeks setting off temperatures in the 80s and 90s and sparking massive and terrifying fires that belch enormous clouds of methane-laced smoke larger than most countries.

***

Last week, a persistent Arctic heatwave re-intensified over Central Siberia, setting off a rash of wildfires while at the same time apparently forcing some of this region’s vast tundra methane stores to erupt. Throughout the weekend, these fires grew, expanding and multiplying, spurring Russia to call up nearly a thousand firefighters and a score of aircraft to combat these raging blazes. Fires continued to erupt throughout the weekend, growing in number to more than 170 separate blazes. This massive region of fires fed a vast cloud of smoke that has now expanded to cover an area about 2000 miles in length and 1200 miles in width.

NASA’s Aqua satellite has provided a recent image focusing in on the area featuring the densest cluster of these fires. The approximately 130 fires shown (but not including all the fires involved) are indicated in red. (Hat tip to Colorado Bob for the head’s up).

Massive wildfires, Russia

More than 130 wildfires, indicated in red, erupt across Siberia. Image source: Aqua/Modis.

Much hotter than average conditions persisted over most of this smog-covered region on Monday as the heat dome high pressure system associated with the scorching Arctic temperatures and wildfires moved retrograde to a feeble Jet Stream and on toward Europe. Daytime temperatures over much of this Arctic region ranged from the mid 70s to the upper 80s with some locations showing highs in the lower 90s.

Arctic temperatures, Daytime, Siberia

Monday daytime temperatures for Central Siberia. Red indicates 77-86 degrees Fahrenheit. Image source: Arctic Weather Maps.

 

These Arctic heatwave conditions are expected to first shift toward Europe then move back over Siberia, eventually settling upon Kamchatka by late this week. According to these model forecasts, heatwave conditions will continue to persist for sections of Siberia at least until the end of this week. So Russia will likely continue to be under the gun for wildfires as the week progresses.

Methane spikes continue

Perhaps the most troubling event to occur in conjunction with Arctic heatwave conditions and a very large wildfire eruption over Central Siberia’s tundras and arboreal forest land is a disturbing methane pulse, also indicated by the Aqua satellite. This methane pulse emerged in conjunction with the heatwave that began last week and appears to have intensified somewhat in recent days. According the Methane Tracker’s A4R, the large clouds of smoke associated with the massive spate of wildfires show heightened methane levels even greater than those first observed last week. In some cases, the methane in the smoke clouds is around 2,000 parts per billion, nearly 200 parts per billion higher than the atmospheric average.

Given these dramatically elevated methane levels, one has to wonder if the fires are enhancing methane emissions from the thawing Siberian tundra and peat bogs.

This particular methane pulse also comes at a time when scientists are increasingly concerned about the potential for enormous methane pulses in the gigaton or tens of gigatons range coming from thawing submerged tundra in the East Siberian Arctic Shelf. A recent Nature article examined the subject in depth and caused broad controversy within the climate community. A NASA mission investigating Arctic methane emissions called CARVE is also seeking to clarify risks involved with the immense methane stores now being unlocked as the Arctic Ocean warms and as the tundra thaws.

The current massive spate of Siberian wildfires now appears to be at least as large those that occurred during June of 2012. In that event, massive blazes sent smoke across the Pacific Ocean to fill valleys on the West Coast of North America. With another week of heatwave conditions set for this region, it is possible that these already extreme conditions will intensify. So we’ll be keeping a close eye on what appears to be a still developing extreme event.

 

 

Barrow Data Shows Large Methane Pulse: Erroneous Reading or Reason For Concern?

Over the past few days, observations of anomalously high methane readings have been coming in from Barrow Alaska. These four reading show a jump of ground level methane concentration at Barrow to 2090-2140 parts per billion (ppb). This is a massive increase over previous measurements of around 1890 ppb. You can see these readings in the graph above in the form of four orange dots in the far upper right hand of the graph.

Barrow is just one reporting station around the Arctic. So, in order to validate any large pulse in methane, we would have to see high readings around the Arctic. As yet, this doesn’t appear to be happening.

In addition, sometimes methane data gets corrupted by bad sensors or faulty process. The result can be anomalously high readings. This has happened before and there is good reason to suspect that these high readings could be caused by a failure of the methane monitoring process.

All that said, this year has seen a number of very strong global warming signals in the Arctic. We’ve seen record warmth over much of the region. We’ve seen record sea ice melt and a trend that shows a potential for ice free Arctic seas within ten years. And we’ve seen an immense increase in melt over the Greenland ice sheet. The sea ice melt is particularly troubling because it is occurring in weather conditions that should not be conducive for melt. And what this points to is a lot of latent heat in the Arctic doing the melting.

So given this context, it would be very unwise to ignore an anomalously high set of methane readings at Barrow. The reason is that heat can destabilize frozen sea bed or tundra methane and result in large pulses of methane hitting the atmosphere. These pulses can contribute large volumes of methane that can dramatically increase atmospheric concentrations. In addition, the over-all trend in the satellite record over the last ten years is for increasing pulses of methane emitted from the Arctic from September to January. Each year, the methane signal has been stronger, so this trend is also cause for concern.

It is still likely that these numbers are the result of error or faulty equipment. But there is a small but not insignificant possibility, perhaps a 20 or 30 percent chance, that this pulse showing up in the Barrow data is real. The fact that four observations are now showing anomalously high readings and that these readings are continuing to rise is serious cause for concern and needs close monitoring.

A large methane pulse in the Arctic this year would be a terrible result. It would add an amplifying global warming feedback to the already strong feedback of sea ice loss and loss of Greenland reflectivity. It would also show that the Arctic environment and the methane stores there are far more sensitive to temperature changes than most scientists had expected. So these observations at Barrow are serious cause for concern.

UPDATE:

I got a response from Andy Crotwell a NOAA scientist specializing in greenhouse gas emissions. He notes that the wind on the day these samples were taken was likely from a developed area where methane readings would have been higher. So he’s pretty sure these are not representative of the Arctic environment and will be listed as outliers in the data.

Links:

http://www.savethearctic.org/

Advertisements
%d bloggers like this: