Record High Methane Levels

Record High Methane Levels

anomaly Arctic Bering Strait heating methane ocean sea surface SST temperature warming

Unknown 8/07/2015 Add Comment

[ click on images to enlarge ]

As the top image shows, sea surface temperature anomalies in the Bering Strait on August 4, 2015, were as high as 8.7°C (15.6°F). Such high anomalies are caused by a combination of ocean heat, of heatwaves over Alaska and Siberia extending over the Bering Strait, and of warm river water run-off.

As the image on the right shows, sea surface temperatures in the Bering Strait were as high as 20.5°C (69.1°F) on August 4, 2015.

As warm water flows through the Bering Strait into the Arctic Ocean, it dives under the sea ice and becomes harder to detect by satellites that typically measure water temperatures at the surface, rather than below the surface.

The image below shows sea surface temperature anomalies from 1971 to 2000, for August 6, 2015, as visualized by Climate Reanalyzer.

Climate Reanalyzer applies a mask over sea-ice-covered gridcells, reducing anomalies in such cells to zero.

Below is a NOAA image, for August 5, 2015, also with anomalies from 1971 to 2000.

Below is another NOAA image, showing anomalies for August 6, 2015. Because the base period is 1961 to 1990, the anomalies are higher. Nonetheless, the yellow areas that feature around the North Pole on above image do not show up on the image below.

In other words, looking at sea surface temperatures alone may lead to underestimations of the temperatures of the water underneath the sea ice. Keeping that in mind, have a look again at the high anomalies on the image below.

The danger is that further decline of the sea ice will lead to rapid warming of the Arctic Ocean, while the presence of more open water will also increase the opportunity for strong storms to develop that can mix high sea surface temperatures all the way down to the seafloor, resulting in destabilization of sediments and triggering releases of methane that can be contained in such sediments in huge amounts.

The image below shows that global mean methane levels as high as 1840 parts per billion (ppb) were recorded on August 4, 2015. Peak methane levels that day were as high as 2477 ppb.

This peak level of 2477 ppb isn't the highest recorded the year. As the image below shows and as discussed in a previous post, methane levels as high as 2845 ppb were recorded on April 25, 2015. The average of the daily peaks for this year up to now is 2355 ppb. Very worrying about the above image are the high levels of methane showing up over the Arctic Ocean.

As above image also shows, the mean methane level of 1840 ppb is in line with expectations, as methane levels rise over the course of the year, to reach a maximum in September. This mean level of 1840 ppb is higher than any mean level since records began.

The image below shows all the World Meteorological Organisation (WMO) annual means that are available, i.e. for the period 1984 through to 2013.

As above image shows, a polynomial trendline based on these WMO data (for the period 1984 through to 2013) points at a doubling of mean global methane levels by about 2040. The added NOAA data are the highest mean in 2014, i.e. 1839 ppb recorded on September 7, 2014, and the above-mentioned level of 1840 ppb recorded on August 4, 2015.

As said, mean global methane levels last year reached its peak in September and the same is likely to occur this year. In other words, this new record is likely to be superseded by even higher levels soon.

The image on the right shows the steady rise of the highest mean daily methane levels that have been recorded recently, indicating that a continued rise can be expected that would put another highest mean level for 2015 on the trendline of above image soon.

Again, the danger is that a warming Arctic Ocean will trigger further methane releases from the seafloor, leading to rapid local warming that in turn will trigger further methane releases, in a vicious cycle of runway warming.

As illustrated by the image on the right, at a 10-year timescale, the current global release of methane from all anthropogenic sources exceeds all anthropogenic carbon dioxide emissions as agents of global warming.

Over the next decade or so, methane emissions are already now more important than carbon dioxide emissions in driving the rate of global warming, and this situation looks set to get worse fast.

Unlike carbon dioxide, methane's GWP does rise as more of it is released. Higher methane levels cause depletion of hydroxyl, which is the main way for methane to be broken down in the atmosphere.

The situation is dire and calls for comprehensive and effective action as discussed at the Climate Plan.  

The image shows all the World Meteorological Organisation (WMO) annual means that are available, i.e. for the period...
Posted by Sam Carana on Friday, August 7, 2015

Arctic Sea Ice Collapse Threatens - Update 3

Arctic Sea Ice Collapse Threatens - Update 3

Arctic collapse heat methane ocean sea ice temperature threat warming

Unknown 8/03/2015 Add Comment

The image below is based on a nullschool.net forecast for August 6, 2015, run on August 2, 2015. It shows temperatures as high as 26.4°C (or 79.4°F) in the north of Canada (green circle). The inset, based on a Climate Reanalyzer forecast for that date, shows that this is as much as 20°C (or 36°F) higher than temperatures that were common in the area only recently, i.e. from 1979-2000.

The satellite image below, captured on August 2, 2015, shows a close-up of the area, with the green circle in the same location as on above image.

Above image shows that there still is some solid ice present to the right of the green circle. This ice may not be able to survive such high temperatures for long. Furthermore, above image shows what looks like smoke plumes from wildfires to the left of the green circle, another sign of the high temperatures in the area and another feedback that will accelerate decline of the snow and ice cover.

Disappearance of sea ice thicker than 4 meters is now taking place north of Canada and Greenland. It looks set to virtually disappear soon, as shown by the 30-day Naval Research Laboratory animation below, ending with a forecast up to August 10, 2015.

In my experience, sea ice thickness hasn't looked this bad for this time of the year since records began, especially when taking the loss of multi-year ice into account. Until now, the thicker multi-year sea ice used to survive the melting season, giving the sea ice strength for the next year, by acting as a buffer to absorb heat that would otherwise melt away the thinner ice. Without multi-year sea ice, the Arctic will be in a bad shape in coming years. Absence of thick sea ice makes it more prone to collapse, and this raises the question whether a collapse could occur not merely some years from now, but even this year.

Above image below shows sea surface temperature anomalies in the Arctic on August 2, 2015.

Greenland's dramatic loss of ice mass over the past few years and the subsequent meltwater may have caused the sea ice to be larger than it would otherwise have been.

Nonetheless, this has not halted the overall decline of the sea ice. As the image on the right shows, sea ice area now is about as low for the time of the year as it was for the three lowest years on record. Furthermore, thick sea ice is shattered if not gone altogether in many places. Meanwhile, ocean heat is at a record high and there's an El Nino that's still gaining strength.

In conclusion, Arctic sea ice looks set to take a further battering over the next few weeks and could end up at a record low around half September 2015. If things get really bad, sea ice collapse could occur and the remaining pieces of sea ice could be driven out of the Arctic Ocean altogether by storms, resulting in a blue ocean event as early as September this year.

The situation is dire and calls for comprehensive and effective action, as discussed at the Climate Plan.

Arctic sea ice area on July 31, 2015.
Posted by Sam Carana on Sunday, August 2, 2015

Arctic Ocean Temperatures Keep Rising

Arctic Ocean Temperatures Keep Rising

Arctic heat methane ocean rise sea ice temperature warming

Unknown 7/25/2015 Add Comment

People's emissions are causing the planet to heat up and more than 93% of this heat goes into the oceans.

People have measured ocean temperatures for a long time. Reliable records go back to at least 1880. Ever since records began, the oceans were colder than they are now. NOAA analysis shows that, on the Northern Hemisphere, the 20th century average for June is 16.4°C (61.5°F). In June 2015, it was a record 0.87°C (1.57°F) higher.

Back in history, there have been times when it was warmer. The last time when it was warmer than today, during the Eemian Period, peak temperature was only a few tenths of a degree higher than today, according to the IPCC. In those days, there was huge melting, accompanied by extreme storms and sea levels that were 5 to 9 m higher than today.

In many ways, the situation now already looks worse than it was in the Eemian. "The warm Atlantic surface current was weaker in the high latitude during the Eemian than today", says Henning Bauch.

Carbon dioxide levels during the Eemian were well under 300 ppm. So, there could well have been more pronounced seasonal differences then, i.e. colder winters that made that the average ocean temperature didn't rise very much, despite high air temperature in summer. By contrast, today's high greenhouse levels make Earth look set for a strong ocean temperature rise.

As illustrated by above image, contained in ocean temperature data from 1880 for the Northern Hemisphere is a polynomial trendline that points at a rise of almost 2°C by 2030. This indicates that temperatures across the Arctic Ocean could soon be even higher than the peak temperature was back in the Eemian Period. Indeed, the Arctic Ocean temperature is rising at a terrifying pace, the more so given that there seems to be no end in sight soon for this rise. 

This rise of almost 2°C by 2030 is not limited to the month of June. As above image shows, it applies to the 12-months period from July 2014 to June 2015 as well.

In some places, the Arctic Ocean is already very warm. Sea surface temperatures around North America have increased to very high levels and they are threatening to further raise the temperature of the Arctic Ocean.

The Arctic sea ice is on the verge of collapse, as discussed in earlier posts such as this one and this one. This dramatic decline of the sea ice in 2015 is the result of a combination of factors, including:

1. High levels of greenhouse gases over the Arctic Ocean, as illustrated by the screenshot below showing high carbon dioxide concentrations over the Arctic (from NASA video).
   
   
   
   Furthermore, methane levels are very high over the Arctic. An earlier image showed methane levels as high as 2512 parts per billion on July 17, 2015, with high methane levels north of Greenland that also showed up on an earlier image at this post.
   
   
2. High levels of ocean heat in the North Atlantic, as illustrated by the image below showing high sea surface temperatures off the east coast of North America; much of this ocean heat will be carried by the Gulf Stream into the Arctic Ocean over the next few months.
   
   
   
3. High sea surface temperatures in the Arctic Ocean, as illustrated by the image below.
   
   
4. High air temperatures over North America and Russia extending over the Arctic Ocean, as illustrated by the image below showing a location well inside the Arctic Circle where temperatures as high as 37.1°C (98.78°F) were recorded on July 2, 2015. (green circle).
   
   
   
5. Wildfires triggered by these heatwaves resulting in darkening compounds settling on snow and ice, making it more prone to melting, as illustrated by the image below showing smoke reaching high up into the Beaufort Sea on July 22, 2015.
   
   
   
6. Very warm river water running into the Arctic Ocean, as illustrated by the image below, showing sea surface temperatures as high as 19°C (66.2°F) off the coast of Alaska on July 19, 2015. 

The danger is that collapse of the sea ice will further accelerate warming in the Arctic, as sunlight that was previously reflected back into space and heat that previously went into melting then will all be absorbed by the Arctic. Furthermore, more open waters will increase the possibility of storms that can mix surface heat down to the bottom of the seafloor, and destabilize sediments that contain large amounts of methane in hydrates and free gas.

Such feedbacks are further discussed at the feedbacks page, including the danger that further warming of the Arctic Ocean will unleash huge methane eruptions from the Arctic Ocean seafloor, in turn driving temperatures up even higher and causing more intense wildfires, heatwaves and further extreme weather events.

The image below shows a non-linear trend that is contained in the temperature data that NASA has gathered over the years, as described in an earlier post. A polynomial trendline points at global temperature anomalies of over 4°C by 2060. Even worse, a polynomial trend for the Arctic shows temperature anomalies of over 4°C by 2020, 6°C by 2030 and 15°C by 2050, threatening to cause major feedbacks to kick in, including albedo changes and methane releases that will trigger runaway global warming that looks set to eventually catch up with accelerated warming in the Arctic and result in global temperature anomalies of 16°C by 2052.

[ click on image to enlarge ]

The situation is dire and calls for comprehensive and effective action, as discussed at the Climate Plan.

People's emissions are causing the planet to heat up and more than 93% of this heat goes into the oceans. People have...
Posted by Sam Carana on Saturday, July 25, 2015

Ocean Temperatures At Record High

Ocean Temperatures At Record High

anomaly Arctic collapse ocean sea ice snow temperature

Unknown 7/21/2015 Add Comment

Of all the excess heat that results from people's emissions, 93.4% goes into oceans. Accordingly, ocean heat has strongly increased over the years.

NOAA analysis shows that, for the oceans on the Northern Hemisphere, the June 2015 sea surface temperature was at a record high 0.87°C (1.57°F) above the 20th century average of 16.4°C (61.5°F), as also illustrated by the graph below.

The most recent 12-month period, July 2014–June 2015, also broke the record (set just last month) for the all-time warmest 12-month period in the 135-year period of record. 

As the above image shows, sea surface temperature anomalies around North America are very high, threatening to further raise temperatures of the Arctic Ocean, which already has very high sea surface temperatures, as also illustrated by the image below. 

As the image below shows, sea surface temperatures as high as 19°C (66.2°F) were recorded in the Bering Strait on July 19, 2015.



The snow depth comparison below shows the situation on July 20, 2015, on the left and a forecast for July 27, 2015, on the right. The green lines indicate areas where sea ice is at melting point. Note the decline of snow cover on Greenland and the Himalayas.

As the continued snow decline on Greenland also illustrates, high temperatures can be expected to keep causing further decline of the snow and ice cover for many weeks to come, given that the minimum sea ice extent is typically reached about half September.

As the image below shows, sea surface temperatures as high as 10.1°C (50.1°F) were recorded in Baffin Bay, off the west coast of Greenland, on July 20, 2015.

On July 21, 2015, temperatures as high as 14°C (57.1°F) were recorded east of Svalbard, an anomaly of 9.7°C (17.4°F), as illustrated by the image below, created with nullschool.net images.

The danger is that warm water will enter the Arctic Ocean and cause the Arctic sea ice to collapse, which could make the Arctic Ocean absorb even more heat. This could unleash huge methane eruptions from the Arctic Ocean's seafloor, in turn driving temperatures up even higher and causing more extreme weather events, wildfires, etc.

The situation is dire and calls for comprehensive and effective action, as discussed at the Climate Plan. 

For the oceans on the Northern Hemisphere, the June 2015 sea surface temperature was at a record high 0.87°C (1.57°F)...
Posted by Sam Carana on Tuesday, July 21, 2015

Heat Wave Forecast For Russia Early June 2015

Heat Wave Forecast For Russia Early June 2015

anomalies Arctic death ESAS heat heatwave India John Davies Russia sea surface SST temperature Veli Albert Kallio wave

Unknown 6/01/2015 Add Comment

Following heat waves in Alaska and the north of Canada, the Arctic looks set to be hit by heat waves along the north coast of Russia in early June, 2015. The image below shows temperature anomalies at the top end of the scale for a large area of Russia forecast for June 6, 2015.

Meanwhile, the heat wave in India continues. It killed more than 2,100 people, reports Reuters, adding that the heat wave also killed more than 17 million chickens in May. The number of people killed by the heat wave is now approaching the 2,541 people killed by the 1998 heat wave in India, which is listed as the record number of deaths due to extreme temperatures in India by the Emergency Events Database.

Further records listed by the database are the well over 70,000 people killed by the 2003 heat wave in Europe and 55,736 people killed by the 2010 heat wave in Russia alone.

On above temperature forecast (left image, top right), temperatures over a large area of India will be approaching the top end of the scale, i.e. 50°C or 120°F. While such temperatures are not unusual in India around this time of year, the length of the heat wave is extraordinary. The heat wave that is about to hit Russia comes with even higher temperature anomalies. Even though temperatures in Russia are unlikely to reach the peaks that hit India, the anomalies are at the top end of the scale, i.e. 20°C or 36°F.

The image below shows a forecast for June 6, 2015, with high temperatures highlighted at four locations (green circles).

Below is a forecast for the jet stream as at June 7, 2015.

The animation below runs the time of the top image (June 6, 2015, 0900 UTC) to the above image (June 7, 2015, 1200 UTC), showing forecasts of the jet stream moving over the Arctic Ocean, with its meandering shape holding warm air that extends from Russia deep into the Arctic Ocean.

Below is another view of the situation.

Jet stream on June 6, 2015, 0900 UTC, i.e. the date and time that corresponds with the top image.

Clicking on this link will bring you to an animated version that also shows the wind direction, highlighting the speed (I clocked winds of up to 148 km/h, or 92 mph) of the jet stream as it moves warm air from Russia into the Arctic Ocean, sped up by cyclonic wind around Svalbard.

This is the 'open doors' feedback at work, i.e. feedback #4 on the feedbacks page, where accelerated warming in the Arctic causes the jet stream to meander more, which allows warm air to enter the Arctic more easily, in a self-reinforcing spiral that further accelerates warming in the Arctic.

The implications of temperatures that are so much higher than they used to be are huge for the Arctic. These high temperatures are heating up the sea ice from above, while rivers further feed warm water into the Arctic Ocean, heating up the sea ice from below.

Furthermore, such high temperatures set the scene for wildfires that can emit huge amounts of pollutants, among which dust and black carbon that, when settling on the sea ice, can cause large albedo falls.

The image below shows Russian rivers that end up in the Arctic Ocean, while the image also shows sea surface temperature anomalies as high as 8.2°C or 14.76°F (at the green circle, near Svalbard).



The big danger is that the combined impact of these feedbacks will accelerate warming in the Arctic to a point where huge amounts of methane will erupt abruptly from the seafloor of the Arctic Ocean.
The image below shows that methane levels as high as 2,566 ppb were recorded on May 31, 2015, while high methane levels are visible over the East Siberian Arctic Shelf.

Below is part of a comment on the situation by Albert Kallio:

As the soils warm up the bacteria in them and the insulating capacities of snow themselves tend to lead snow cover melting faster the warmer the soil it rests on becomes. (Thus the falling snow melts very rapidly on British soil surface if compared to Finland or Siberia where the underlying ground is much colder, even if occasionally the summers have similar or even higher temperatures).

The large snow cover over the mid latitude land masses is a strong negative feedback for the heat intake from the sun if the season 2015 is compared with the season 2012, but the massive sea ice and polar air mass out-transportation equally strongly weakens formation of new sea ice around the North Pole (and along the edges of the Arctic Ocean) as the air above the Arctic Ocean remains warm. The pile up of thin coastal ice also increases vertical upturning of sea water and this could have detrimental effects for the frozen seabed that is storing methane clathrates. The sunlight intake of the sea areas where sea ice has already disappeared corresponds largely with the 2012 season.

The inevitable snow melting around the Arctic Ocean will also transport record volumes of warmed melt water from the south to the Arctic Ocean. The available heat in the Arctic may also be later enhanced by the high sea water temperatures that prevail along the eastern and western coasts of North America, as well as El Nino event increasing temporarily air and sea surface temperatures. This leads to more depressions around Japan and Korea from where the warm air, storms and rains migrate towards Alaska and pull cold air away from Arctic over Russia, while pushing warm air through the Baring Strait area and Alaska to the Arctic Ocean region.

Forecasting seasonal out comes is likely to be increasingly difficult to make due to increasing number of variables in the seasonal melting processes and the resulting lack of historic precedents when the oceans and Arctic has been as warm as today. Thus the interplay of the opposing forces makes increasingly chaotic outcomes, in which the overall trend will always be for less ice and snow at the end of the season. Because of these reasons - including many others not explicitly mentioned here - the overall outcome for the blue ocean, or the ice-free Arctic Ocean, will be inevitable.

Whether the loss of sea ice happens this summer, or next, or one after that, the problem isn't going to go away and more needs to be done to geoengineer to save Arctic ice and wildlife dependent on summer sea ice.

John Davies responds:

Albert Kallio is absolutely right in saying that warmer temperatures are leading to a blue ocean event though the problem remains in which year this will happen. Additionally Methane is being released from the bottom of the ocean leading to increased Methane concentrations and all that means for a destabilising global climate. Frustratingly, the higher temperatures and increasing Methane concentrations are not yet quite sufficient for us to persuade the scientific community and the public that Armageddon is on the way. Hence it is not yet possible to be in a position to persuade the world community of the urgent need for Geo-engineering to save the Arctic and Global climate. However we may reach this situation in the near future and that will be the only time when it might be possible to save the global climate and prevent Armageddon.

The situation is dire and calls for comprehensive and effective action, as discussed at the Climate Plan page.

This image shows Russian rivers that end up in the Arctic Ocean, while it also shows sea surface temperature anomalies...
Posted by Sam Carana on Monday, June 1, 2015

Methane Levels Early 2015

Methane Levels Early 2015

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Unknown 3/27/2015 Add Comment

The image below shows highest mean methane readings on one day, i.e. March 10, compared between three years, i.e. 2013, 2014 and 2015, at selected altitudes. The comparison indicates that the increase of methane in the atmosphere is accelerating, especially at higher altitudes.

The table below shows the altitude equivalents in mb (millibar) and feet.

56925 feet	44689 feet	36850 feet	30569 feet	25543 feet	19819 feet	14383 feet	8367 feet	1916 feet
74 mb	147 mb	218 mb	293 mb	367 mb	469 mb	586 mb	742 mb	945 mb

This rise in global mean methane levels appears to go hand in hand with much higher peak readings, especially at higher altitudes.

From January 1 to March 20, 2015, methane levels reached levels as high as 2619 ppb (on January 12, 2015), while peak daily levels averaged 2373 parts per billion (ppb). At the start of the year, global mean methane levels typically reach their lowest point, while highest mean levels are typically reached in September. Highest daily global mean methane levels for the period from January 1, 2015, to March 20, 2015, ranged from 1807 ppb (January 6, 2015) to 1827 ppb (March 5, 2015).

Further study of the locations with high methane levels indicates that much of the additional methane appears to originate from releases at higher latitudes of the Northern Hemisphere, in particular from the Arctic Ocean, from where it is over time descending toward the equator (methane will typically move closer to the equator over time as it rises in altitude, as discussed in this earlier post).

The largest source of additional methane appears to be emissions from the seabed of the Arctic Ocean. Annual emissions from hydrates were estimated to amount to 99 Tg annually in a 2014  post (image below).

The image below, based on data from the IPCC and the World Metereological Organization (WMO), with an added observation from a NOAA MetOp satellite image, illustrates the recent rise of methane levels and the threat that methane levels will continue to rise rapidly.

What causes these methane eruptions?

Methane eruptions from the seafloor of the Arctic Ocean appear to be primarily caused by rising ocean heat that is carried by the Gulf Stream into the Arctic Ocean. The image below shows sea surface temperatures of 20.9°C (69.62°F, green circle left) recorded off the coast of North America on March 14, 2015, an anomaly of 12.3°C (36.54°F).

[ click on image to enlarge ]

Furthermore, both methane eruptions from the Arctic Ocean seafloor and demise of the Arctic sea ice and snow cover are feedbacks that can interact and amplify each other in non-linear ways, resulting in rapid and intense temperature rises, as illustrated by the image below.

Diagram of Doom - for more background, see Feedbacks

How high could temperatures rise?

Worryingly, a non-linear trend is also contained in the temperature data that NASA has gathered over the years, as described in an earlier post. A polynomial trendline points at global temperature anomalies of over 4°C by 2060. Even worse, a polynomial trend for the Arctic shows temperature anomalies of over 4°C by 2020, 6°C by 2030 and 15°C by 2050, threatening to cause major feedbacks to kick in, including albedo changes and methane releases that will trigger runaway global warming that looks set to eventually catch up with accelerated warming in the Arctic and result in global temperature anomalies of 16°C by 2052.

[ click on image to enlarge ]

Action

The situation is dire and calls for comprehensive and effective action, as discussed at the Climate Plan blog.

Comparison between three years, i.e. 2013, 2014 and 2015, of highest mean methane readings at selected altitudes on...
Posted by Sam Carana on Friday, March 27, 2015

The Mechanism

The Mechanism

Arctic clathrates heat hydrates mechanism methane Natalia Shakhova ocean permafrost Peter Wadhams sea ice temperature

Unknown 2/28/2015 Add Comment

What is the mechanism behind accelerated warming of the Arctic Ocean, huge abrupt methane eruptions from the seafloor of the Arctic Ocean and skyrocketing temperatures?

1. Potential for Methane Release in Arctic

Vast amounts of methane are stored in hydrates under the seafloor of the Arctic Ocean. Furthermore, vast amounts of methane in the form of free gas are contained in sediments under the seafloor of the Arctic Ocean. Thirdly, vast amounts of carbon are frozen in the permafrost and much may enter the atmosphere in the form of methane as the permafrost continues to thaw.

Natalia Shakhova et al. in 2010 estimated the accumulated potential for the East Siberian Arctic Shelf (ESAS) region alone (image on the right) as follows:
- organic carbon in permafrost of about 500 Gt
- about 1000 Gt in hydrate deposits
- about 700 Gt in free gas beneath the gas hydrate stability zone.

In early 2014, Sam Carana estimated annual methane emissions from hydrates and permafrost at 100 Tg (i.e. 0.1 Gt). This methane will contribute to further warming of the air over the Arctic and the North Atlantic, causing further extreme weather events, such as heatwaves and storms along the path of the Gulf Stream from the North Atlantic into the Arctic Ocean, in turn triggering further releases from hydrates at the seafloor of the Arctic Ocean and threatening to escalate into runaway global warming.

Such methane eruptions are caused by warming water of the Arctic Ocean, which in turn is due to emissions by people. Some elements of the mechanism causing methane to erupt from the seafloor are described in more detail below.

2. Ocean Heat

From: Ocean Temperature Rise continues

Above graph, based on NOAA data, shows a polynomial trendline pointing at an October Northern Hemisphere sea surface temperature anomaly rise of more than 5°C (9°F) by 2050, compared to the 20th century average, from an earlier post.

Waters at greater depth are also warming rapidly, as illustrated by the image on the right, from an earlier post, showing a rise in ocean heat up to 2000 m deep that has more than doubled over the past decade. Data from 2005 through to 2014 contain a polynomial trendline that points at a similar rise by 2017, followed by an even steeper rise.

The North Atlantic is warming rapidly, with sea surface temperature anomalies as high as a 12°C (21.6°F) recorded east of North America earlier this year, as illustrated by the image below.

A warmer North Atlantic is a major contributor to the rapidly warming waters of the Arctic Ocean, since the Gulf Stream keeps carrying warmer water into the Arctic Ocean all year long.

A further contributor is a warmer North Pacific.

Further contributions come from the combined impact of numerous feedbacks, in particular changing winds and currents, cryosphere changes and methane releases, as further described below.

From: Watch where the wind blows

3. Feedbacks: Changing Winds and Currents, Cryosphere Changes and Methane

- Changed Winds and Currents

Emissions by people are not only causing temperatures of the atmosphere and oceans to rise, they are also causing winds and ocean currents to change. Such changes can in turn result in heatwaves that are more intense and that persist for prolonged periods. Furthermore, strong northbound winds, combined with strong precipitation and waves can speed up the volume of warm water carried by Gulf Stream into the Arctic Ocean, as discussed in an earlier post. 

- Arctic Sea Ice

A warming atmosphere, warming oceans and decline of the Arctic snow and ice cover all go hand in hand. The IPCC concluded in AR5 that, for RCP8.5, the Arctic Ocean will likely be nearly ice-free in September before mid-century. Prof. Peter Wadhams warned, back in 2012, that the Arctic Ocean could be virtually ice-free within a few years. An exponential trendline based on sea ice volume observations shows that sea ice looks set to disappear in 2019, while disappearance in 2015 is within the margins of a 5% confidence interval, reflecting natural variability, as discussed at the FAQ page.

- Permafrost

Permafrost decline will cause Arctic temperatures to rise, due to albedo change and due to carbon that is contained in the permafrost and that can be expected to be released in the form of methane or carbon dioxide as the permafrost thaws. The image below pictures permafrost decline as foreseen by the IPCC in AR5. 

Obviously, rapid decline of the sea ice will come with albedo changes that will also make the permafrost decline more strongly than the IPCC foresees, while they will also cause even more extreme weather events. One of the dangers is that huge amounts of warmer water will flow from rivers into the Arctic Ocean, as discussed below.

- Warmer Water From Rivers

More sunlight getting absorbed in the Arctic will accelerate warming of the Arctic Ocean directly, while there will also be warmer water flowing into the Arctic Ocean from rivers in Siberia and North America, fueled by stronger and longer heatwaves, storms and wildfires. 

map from: http://en.wikipedia.org/wiki/File:Rs-map.png

Above map shows that a number of large rivers in Siberia end up in the Arctic Ocean. Another large river is the Mackenzie River, which ends in the Beaufort Sea, north of Alaska, where sea surface temperatures of about 20°C (68°F) were recorded in 2013, as the image below illustrates.

Another area of concern, also marked with a purple oval in the image below, is located in the north of Canada.

More extreme weather events include heat waves, storms, floods and wildfires, all of which can contribute to more rapid warming of the Arctic Ocean.

The combined effect of all the above will be that methane that is now contained in the form of free gas and hydrates in sediments under the Arctic Ocean, can be expected to be increasingly released as the Arctic Ocean warms further.

- Methane 

Of the vast amounts of methane stored in the Arctic, much of it is prone to be released with further temperature rises, as discussed in this earlier post and in this earlier post. Cracks in sediments used to be filled with ice. Warmer water is now melting the ice that used to sit in cracks. This ice has until now acted as a glue, holding the sediment together. Moreover, the ice in the cracks has until now acted as a barrier, a seal, that prevented the methane contained in those sediments from escaping. In a video interview with Nick Breeze, Natalia Shakhova mentions a sample of sediment taken from the ESAS seafloor in 2011 that turned out to be ice-free to a depth of 53 m at water temperatures varying from -0.6˚C to -1.3˚C. Back in 2008, Natalia Shakhova et al. considered release of up to 50 Gt of predicted amount of hydrate storage as highly possible for abrupt release at any time.

The image below, based on data from the IPCC and the World Metereological Organization (WMO), with an added observation from a NOAA MetOp satellite image, illustrates the recent rise of methane levels and the threat that methane levels will continue to rise rapidly.

When looked at from a longer range of years, above image fits in the black square on the image below.

The image below shows exponential rise based on data of East Siberian Arctic Shelf (ESAS) releases alone, as discussed in an earlier post.

Non-linear rise is supported by the fact that methane's lifetime increases as more methane enters the atmosphere. As the image below shows, peak methane levels have been very high recently.

All these feedbacks can interact and amplify each other in non-linear ways, resulting in rapid and intense temperature rises, as illustrated by the image below.

Diagram of Doom - for more background, see Feedbacks

4. Runaway Global Warming

The threat is that such rapid temperature rises will appear at first in hotspots over the Arctic and eventually around the globe, while also resulting in huge temperature swings that could result in depletion of supply of food and fresh water, as further illustrated by the above image, from an earlier post, and the image below, from another earlier post.

Rapidly rising temperatures will cause stronger evaporation of sea water. Since water vapor is one of the strongest greenhouse gases, this can further contribute to the non-linear temperature rises pictured above.

In conclusion, the situation is dire and calls for comprehensive and effective action, as discussed at the Climate Plan blog.

Post by Sam Carana.