Ocean Heat Depth

Ocean heat at the equator

On November 24, 2015, equatorial waters at ≈100 m (328 ft) depth at 110-135°W were over 6°C (10.8°F) warmer than average in 1981-2000, as illustrated by above image. The animation below shows equatorial ocean heat over the past few months, illustrating that temperature anomalies greater than 6°C (10.8°F) occurred throughout this period at depths greater than 100 m (328 ft).

The danger of ocean heat destablizing clathrates in the Arctic

The danger is that ever warmer water will reach the seafloor of the Arctic Ocean and destabilize methane that is held there in sediments the form of free gas and hydrates.

So, how comparable is the situation at the equator with the situation in the Arctic? How much heating of the Arctic Ocean has taken place over the past few years?

The image on the right, produced with NOAA data, shows mean coastal sea surface temperatures of over 10°C (50°F) in some areas in the Arctic on August 22, 2007.

In shallow waters, heat can more easily reach the bottom of the sea. In 2007, strong polynya activity caused more summertime open water in the Laptev Sea, in turn causing more vertical mixing of the water column during storms in late 2007, according to this study, and bottom water temperatures on the mid-shelf increased by more than 3°C (5.4°F) compared to the long-term mean.

This study finds that drastic sea ice shrinkage causes increase in storm activities and deepening of the wind-wave-mixing layer down to depth ~50 m (164 ft) that enhance methane release from the water column to the atmosphere. Indeed, the danger is that heat will warm up sediments under the sea, containing methane in hydrates and as free gas, causing large amounts of this methane to escape rather abruptly into the atmosphere.

The image below, replotted by Leonid Yurganov from a study by Chepurin et al, shows sea water temperature at different depths in the Barents Sea, as described in an earlier post.

The image below is from a study published in Nature on November 24, 2013, showing water temperatures measurements taken in the Laptev Sea from 1999-2012.

Water temperatures in Laptev Sea. Red triangles: summer. Blue triangles: winter. Green squares: historic data.
From Shakhova et al., (2013) doi:10.1038/ngeo2007

Before drawing conclusions, let's examine some peculiarities of the Arctic Ocean more closely, specifically some special conditions in the Arctic that could lead to greater warming than elsewhere and feedbacks that could accelerate warming even more.

Amount of methane ready for release

Sediments underneath the Arctic Ocean hold vast amounts of methane. Just one part of the Arctic Ocean alone, the East Siberian Arctic Shelf (ESAS, rectangle on map below, from the methane page), holds up to 1700 Gt of methane. A sudden release of just 3% of this amount could add over 50 Gt of methane to the atmosphere, and experts consider such an amount to be ready for release at any time (see above image).



Total methane burden in the atmosphere now is 5 Gt. The 3 Gt that has been added since the 1750s accounts for almost half of the (net) total global warming caused by people. The amount of carbon stored in hydrates globally was in 1992 estimated to be 10,000 Gt (USGS), while a more recent estimate gives a figure of 63,400 Gt (Klauda & Sandler, 2005). The ESAS alone holds up to 1700 Gt of methane in the form of methane hydrates and free gas contained in sediments, of which 50 Gt is ready for abrupt release at any time.



Imagine what kind of devastation an extra 50 Gt of methane could cause. Imagine the warming that will take place if the methane in the atmosphere was suddenly multiplied by 11.

Whiteman et al. recently calculated that such an event would cause $60 trillion in damage. By comparison, the size of the world economy in 2012 was about $70 trillion.

Shallow waters in the Arctic Ocean

Shallow waters and little hydroxyl

The danger is particularly high in the shallow seas that are so prominent in the Arctic Ocean, as illustrated by the light blue areas on the image on the right, from an earlier post.

Much of the waters in the Arctic Ocean are less than 50 m deep. Being shallow makes waters prone to warm up quickly during summer temperature peaks, allowing heat to penetrate the seabed.

This can destabilize hydrates and methane rising through shallow waters will then also enter the atmosphere more quickly, as it rises abruptly and in plumes.

Elsewhere in the world, releases from hydrates underneath the seafloor will largely be oxidized by methanotroph bacteria in the water and where methane does enter the atmosphere, it will quickly be oxidized by hydroxyl. In shallow waters, however, methane released from the seabed will quickly pass through the water column.

Large abrupt releases will also quickly deplete the oxygen in the water, making it harder for bacteria to break down the methane.

Very little hydroxyl is present in the atmosphere over the poles, as illustrated by the image on the right, showing global hydroxyl levels, from an earlier post.

In case of a large abrupt methane release from the Arctic Ocean, the little hydroxyl that is present in the atmosphere over the Arctic will therefore be quickly depleted, and the methane will hang around for much longer locally than elsewhere on Earth.

Shallow waters make the Arctic Ocean more prone to methane releases, while low hydroxyl levels make that methane that enters the atmosphere in the Arctic will contribute significantly to local warming and threaten to trigger further methane releases.

High levels of insolation in summer in the Arctic

Furthermore, the amount of solar radiation received by the Arctic at the June Solstice is higher than anywhere else on Earth, as illustrated by the image below, showing insolation on the Northern Hemisphere by month and latitude, in Watt per square meter, from an earlier post.

Warm water enters Arctic Ocean from Atlantic and Pacific Oceans

What further makes the situation in the Arctic particularly dangerous is that waters are not merely warmed up from the top down by sunlight that is especially strong over the Arctic Ocean in summer on the Northern Hemisphere, but also by warm water that flows into the Arctic Ocean from rivers and by warm water that enters the Arctic Ocean through the Bering Strait and through the North Atlantic Ocean. The latter danger is illustrated by the image below, from an earlier post.

Feedbacks

Furthermore, there are feedbacks that can rapidly accelerate warming in the Arctic, such as albedo losses due to loss of sea ice and snow cover on land, and changes to the jet stream resulting in more extreme weather. These feedbacks, described in more details at this page, are depicted in the image below.

Methane

Above image shows that methane levels on December 3, 2015, were as high as 2445 parts per billion (ppb) at 469 millibars, which corresponds to an altitude of 19,810 feet or 6,041 m.

The solid magenta-colored areas (levels over 1950 ppb) that show up over a large part of the Arctic Ocean indicate very strong methane releases.

Note there are many grey areas on above image. These are areas where no measurements could be taken, which is likely due to the strength of winds, rain, clouds and the jet stream, as also illustrated by the more recent (December 5, 2015) images on the right.

The polar jet stream on the Northern Hemisphere shows great strength, with speeds as high as 243 mph or 391 km/h (over a location over japan marked by green circle) on December 5, 2015.

So, high methane levels may well have been present in these grey areas, but didn't show up due to the weather conditions of the moment.

Furthermore, the white geometric areas are due the way the satellite takes measurements, resulting in areas that are not covered.

Finally, it should be noted that much of the methane will have been broken down in the water, before entering the atmosphere, so what shows up in the atmosphere over the Arctic is only part of the total amount of methane that is released from the seafloor.

In conclusion, the high methane levels showing up over the Arctic indicate strong methane releases from the seafloor due to warm waters destabilizing sediments that contain huge amounts of methane in the form of free gas and hydrates.

Climate Plan

As global warming continues, the risk increases that greater ocean heat will reach the Arctic Ocean and will cause methane to be released in large quantities from the Arctic Ocean seafloor. The 2015 El Niño has shown that a huge amounts of ocean heat can accumulate at a depth greater than 100 m (328 ft). Conditions in the Arctic and feedbacks make that methane threatens to be released there abruptly and in large quantities as warming continues.

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

On November 24, 2015, equatorial waters at ≈100 m (328 ft) depth at 110-135°W were over 6°C (10.8°F) warmer than average...
Posted by Sam Carana on Friday, December 4, 2015

Methane Monster II ~ Demise of the Arctic

Presentation by Jennifer Hynes on runaway feedbacks in the Arctic and the resulting threat of near-term human extinction. At https://www.youtube.com/watch?v=7zUUZAomj6E

There are links to the transcript and to the complete set of slides of the presentation at Jennifer Hynes' blog.

In case you are looking for the earlier presentation by Jennifer Hynes, called 'The Arctic Methane Monster's Rapid Rise', it's at youtube.com/watch?v=a9PshoYtoxo and is also displayed below.

Disappearance Of Thick Arctic Sea Ice

[ view full image at facebook ]

Arctic sea ice is in a horrible state. On August 16, 2015, Arctic sea ice extent was 5.786 million square km, the smallest extent on record for this time of year except for the years 2007, 2011 and 2012, as illustrated by the image on the right.

The situation today is even worse than one might conclude when looking at sea ice extent alone. Thick sea ice is virtually absent compared to the situation in the year 2012 around this time of year, as illustrated by the image below comparing sea ice thickness on August 16, 2012 (left) with August 16, 2015 (right).

The ice used to be over 4 m thick, or over 13 ft thick, north of Greenland and the Canadian Archipelago. This thick multi-year ice has been a feature of the Arctic sea ice for over 100,000 years. It used to be there all year long, unlike the thinner ice that could melt away entirely during the melting season.

The disappearance of this thick multi-year ice is a major development. Why? 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, and huge amounts of heat that would otherwise go into melting the ice will instead be warming up the Arctic Ocean, further accelerating warming of its waters.

Absence of thick sea ice makes it more prone to collapse, and this raises the question whether the sea ice could collapse soon, even this year. Sea ice works like a mirror. Without sea ice, sunlight that was previously reflected back into space, will instead be absorbed by the Arctic. Albedo changes in the Arctic alone could more than double the net radiative forcing resulting from the emissions caused by all people of the world, as calculated by Prof. Peter Wadhams back in 2012.

Furthermore, there is a danger that loss of the sea ice will weaken the currents that currently cool the bottom of the sea, where huge amounts of methane may be present in the form of free gas or hydrates in sediments. This danger is illustrated by the image below by Reg Morrison, from an earlier post.

Absence of sea ice also goes hand in hand with opportunities for storms to develop over the Arctic Ocean. Such storms could push the remaining sea ice out of the Arctic Ocean. Such storms could also mix surface heat all the way down to the seafloor, where methane could be contained in sediments.

As described in an earlier post, sea surface anomalies of over 5 degrees Celsius were recorded in August 2007 (NOAA image right). Strong polynya activity caused more summertime open water in the Laptev Sea, in turn causing more vertical mixing of the water column during storms in late 2007, as described in this study, and bottom water temperatures on the mid-shelf increased by more than 3 degrees Celsius compared to the long-term mean.

Indeed, the danger is that heat will warm up sediments under the sea, containing methane in hydrates and as free gas, causing large amounts of this methane to escape rather abruptly into the atmosphere.

The image on the right, from a study by Hovland et al., shows that hydrates can exist at the end of conduits in the sediment, formed when methane did escape from such hydrates in the past.

Heat can travel down such conduits relatively fast, warming up the hydrates and destabilizing them in the process, which can result in huge abrupt releases of methane.

Since waters can be very shallow in the Arctic, much of the methane can then rise up through these waters without getting oxidized. As the methane causes further warming in the atmosphere, this will contribute to the danger of even further methane escaping, further accelerating local warming, in a vicious cycle that can lead to catastrophic conditions well beyond the Arctic. For additional feedbacks in the Arctic, see the feedbacks page. 

At the same time, ocean heat is at a record high and there's an El Niño that's still gaining strength. This ocean heat is likely to reach the Arctic Ocean in full strength by October 2015, at a time when sea ice may still be at its minimum. The image below shows sea surface temperatures on August 16, 2015 (left) and anomalies (right).

How warm is the water entering the Arctic Ocean? Merely looking at sea surface temperatures could make one overlook the full extent of the predicament we are in. Ocean heat traveling underneath the sea surface can be even warmer than temperatures showing up at the surface. This is illustrated by the image below indicating that on August 16, 2015, warm water emerged at the sea surface near Svalbard with temperatures as high as 14.9°C or 58.7°F, a 9.5°C or 17.1°F anomaly.

There still is about a month to go before sea ice can be expected to reach its minimum, at around half September 2015, while sea currents will continue to carry warmer water into the Arctic Ocean for months to come.

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

Thick sea ice is virtually absent compared to the situation in the year 2012 around this time of year, as illustrated by...
Posted by Sam Carana on Tuesday, August 18, 2015

It's time to 'Do the math' again

By David Spratt

Have we gone mad? A new report released today explains why contemporary climate change policy-making should be characterised as increasingly delusional.

As the deadline approaches for submissions to the Australian government's climate targets process, there is a flurry of submissions and reports from advocacy groups and the Climate Change Authority.

Most of these reports are based on the twin propositions that two degrees Celsius (2°C) of global warming is an appropriate policy target, and that there is a significant carbon budget and an amount of "burnable carbon" for this target, and hence a scientifically-based escalating ladder of emission-reduction targets stretching to mid-century and beyond.

A survey of the relevant scientific literature by David Spratt, "Recount: It's time to 'Do the math' again", published today by Breakthrough concludes that the evidence does not support either of these propositions.

The catastrophic and irreversible consequences of 2°C of warming demand a strong risk-management approach, with a low rate of failure. We should not take risks with the climate that we would not take with civil infrastructure.

There is no carbon budget available if 2°C is considered a cap or upper boundary as per the Copenhagen Accord, rather than a hit-or-miss target which can be significantly exceeded; or if a low risk of exceeding 2°C is required; or if positive feedbacks such as permafrost and other carbon store losses are taken into account.

Effective policy making can only be based on recognising that climate change is already dangerous, and we have no carbon budget left to divide up. Big tipping-point events irreversible on human time scales such as in West Antarctica and large-scale positive feedbacks are already occurring at less than 1°C of warming. It is clear that 2°C of climate warming is not a safe cap.

In reality, 2°C is the boundary between dangerous and very dangerous climate change and 1°C warmer than human civilisation has ever experienced.

In the lead up to the forthcoming Paris talks, policy makers through their willful neglect of the evidence are in effect normalising a 2.5–3°C global warming target.

This evidence in "Recount: It's time to 'Do the math' again" demonstrates that action is necessary at a faster pace than most policy makers conceive is possible.

Related

- It's time to 'Do the math' again
http://www.climatecodered.org/2015/04/its-time-to-do-math-again.html

- RECOUNT - It's time to 'Do the math' again
http://media.wix.com/ugd/148cb0_938b5512abfa4d4e965ec8cc292893f7.pdf

- Two degrees of warming closer than you may think
http://arctic-news.blogspot.com/2015/02/two-degrees-of-warming-closer-than-you-may-think.html

- The real budgetary emergency and the myth of "burnable carbon"
http://arctic-news.blogspot.com/2014/05/the-real-budgetary-emergency-and-the-myth-of-burnable-carbon.html

It's time to 'Do the math' again | by David Spratt http://arctic-news.blogspot.com/2015/04/its-time-to-do-math-again.html

Posted by Sam Carana on Thursday, April 23, 2015

Watch where the wind blows

The Arctic looks set to be pummeled by strong winds on February 5, 2015, as shown by the Climate Reanalyzer forecast below.

The video below, based on Climate Reanalyzer images, watch the situation unfold over a period of 9 days

Strong winds can increase the transport of warm water into the Arctic Ocean by the Gulf Stream. The video shows strong winds repeatedly developing off the North American east coast and moving along the path of the Gulf Stream, all the way into the Arctic Ocean, all in a matter of days.

Emissions are causing greater warming of the Gulf Stream and the Arctic. As a result, there is less temperature difference between the equator and the Arctic, slowing down the speed at which the jet streams circumnavigate the globe, while the jets can also become wavier, which in turn can cause extreme weather events.

In this case, what fuels these winds is the temperature difference between an area off the east coast of North America where temperatures are much higher than they used to be on the one hand, and an area in Siberia where temperatures are extremely low on the other hand. Wind flows from a warm area to a cold area, and the greater the temperature difference, the stronger the wind will blow.

The image below shows that, on February 3rd, 2015, a sea surface temperature of 21°C (69.8°F) was recorded off the east coast of North America (green circle), which constitutes a 12°C (21.6°F) anomaly. Anomalies as high as 12°C were also recorded on February 4, 2015.

click on image to enlarge

Changes to the jet streams can thus fuel strong winds, and such winds can bring warmer air into the atmosphere over the Arctic Ocean. On February 5, 2015, surface temperatures over a large part of the Arctic Ocean were more than 20°C (36°F) warmer compared to what they were from 1985 to 1996.

Extreme weather events, as a result of changes to the jet streams and polar vortex, are depicted as feedback #19 in the diagram below, while storms that bring warmer air into the atmosphere over the Arctic Ocean are depicted as feedback #5,

Besides increasing the transport of warm water into the Arctic Ocean and bringing warmer air into the atmosphere over the Arctic Ocean, strong winds can also break up the sea ice by sheer brute force of the waves caused by the wind.

Waves as high as 10.61 m (34.81 ft) were recorded south of Greenland on February 4, 2015, while waves as high as 7.05 m (23.13 ft) were recorded on the edge of the Arctic sea ice (east of Svalbard) on February 5, 2015, as shown on the combination image below.

Waves that break up the sea ice into smaller pieces can speed up melting, especially in summer. More wind also means more water evaporation, and warmer air holds more water vapor, so this can result in huge rainstorms that can rapidly devastate the integrity of the ice. Strong winds thus constitute a feedback that can result in more open waters in the Arctic Ocean (feedback #6 on the diagram below).

Furthermore, strong winds can speed up the currents that will eventually move sea ice out of the Arctic Ocean into the Atlantic Ocean (feedback #7). Wavy waters catch more sunlight than still water (feedback #8). Decline of the Arctic snow and ice cover results in more sunlight being absorbed by the Arctic, thus further heating up the water of the Arctic ocean (feedback #1).

The dual image below, with images from Climate Reanalyzer, shows high sea surface temperatures around North America and at the edges of the Arctic sea ice. This contributes to surface temperatures that are 20°C (36 °F) higher than what they used to be in Eastern Siberia. At the same time, temperatures on land elsewhere in Siberia, on the North Pole and in parts of Canada and Greenland can go down to 40 degrees below zero.

Accelerated warming of the Arctic is changing the jet streams, in turn contributing to the likelyhood that such strong winds will hit the Arctic. The high temperature difference between the hot spot off the North American east coast and the cold spot over Siberia fuels such strong winds. The dual images below show the jet stream's elongated path over Greenland. Accordingly, temperature anomalies in Greenland are reaching the top end of the scale.

The big danger is that such strong winds will warm up the Arctic Ocean and cause huge amounts of methane to erupt from its seafloor.

The image below shows that methane levels as high as 2503 ppb were recorded on January 31, 2015.

Such methane eruptions constitute yet another feedback that further contributes to warming in the Arctic. For more feedbacks, see the image below.

from:  climateplan.blogspot.com/p/feedbacks.html

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

Another Heatwave Hits Arctic

As parts of Canada, Greenland and Russia are hit by -40 degrees temperatures (anomalies at the bottom end of the scale), parts of the Arctic are experiencing temperatures above freezing (anomalies at the top end of the scale), as illustrated by the image below.

[ click on image to enlarge ]

Temperatures in the Arctic are much higher than they used to be and this situation further accelerates warming in the Arctic, due to a number of feedbacks.

One such feedbacks has been coined the ‘open doors feedback’. Indeed, the situation is much like leaving the fridge door open. This allows cold air to more easily move out of the fridge, i.e. the Arctic, resulting in the cold temperatures over North America that have received extensive news coverage in the media. At the same time, warm air can move more easily into the fridge, i.e. the Arctic, and this is one of the reasons why the Arctic is hit by temperatures that are so much higher than what used to be normal.

The situation has been described in a number of earlier posts such as this one, as well in a recent interview with Jennifer Francis. As the Arctic warms more rapidly than the rest of the world, there's less temperature difference between the Arctic and the equator, resulting in the jet stream going around the globe at a lower speed with more elongated loops.

The left chart on above image shows such an elongated loop going north along the east coast of Greenland, then bending before Scandinavia and moving over the north of Greenland, then going around the North Pole and moving back to Scandinavia. This loop is not very visible on the chart, because the jet stream moves faster along straight tracks, and this chart highlights wind speed more than it highlights the path of the jet stream. Yet, the shape of this loop is very important, as it traps warmer air north of Greenland.

BTW, a weaker jet stream also elevates the chance of heat waves elsewhere, which can indirectly warm up the Arctic. Examples of this are heat waves over the Gulf Stream as it crosses the Atlantic Ocean, resulting in warmer water being carried into the Arctic Ocean, and heat waves over Siberia and North America, resulting in warming up of rivers that end in the Arctic Ocean.

Anyway, to get back to the current heatwave, there are a number of reasons why temperatures in the Arctic are so high at the moment. One of the biggest reasons is ocean heat, which has reached very high levels, especially in the North Atlantic, while the Gulf Stream keeps transporting warmer water from the North Atlantic into the Arctic Ocean (i.e. water that is warmer than the water in the Arctic Ocean). This warms up the seafloor of the Arctic Ocean, resulting in methane erupting from the seafloor, with a strong immediate local warming impact in the Arctic, thus further accelerating warming in the Arctic in another one of these self-reinforcing feedback loops, as pictured in the image below.

Further feedbacks that accelerate warming in the Arctic are discussed at the feedbacks page.

Without effective and comprehensive action, these feedbacks threaten to lead to runaway warming, i.e. abrupt climate change causing mass death and destruction, and resulting in extinction at massive scale, as depicted in the image below and as described in this earlier post.

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

Post by Sam Carana.

Ocean Temperature Rise Continues

Ocean Temperature Rise

Of all the excess heat that results from people's emissions, 93.4% goes into oceans. Accordingly, the temperature of oceans has risen substantially.

NOAA analysis shows that the most recent 12-month period, November 2013–October 2014, broke the record (set just last month) for the all-time warmest 12-month period in the 135-year period of record. The global oceans were the warmest on record for October. For January–October, the average global sea surface temperature was also record high.

The danger is that ocean temperatures will continue to rise, especially in the North Atlantic, and that the Gulf Stream will keep carrying ever warmer water from the North Atlantic into the Arctic Ocean, threatening to unleash huge methane eruptions from the Arctic Ocean's seafloor, in turn causing even higher temperatures and more extreme weather events, wildfires, etc.


High Methane Levels

High methane levels were recorded over the Arctic Ocean in October, as discussed in this earlier post, and were sustained in November, as discussed in this post. Methane levels as high as 2717 ppb were recorded on November 16, 2014, p.m, by the MetOp-1 satellite at 469 mb (i.e. 19,820 ft or 6,041 m altitude), as the image below shows.

Methane levels as high as 2549 ppb were recorded on November 19, 2014, p.m, by the MetOp-2 satellite at 586 mb (i.e. 14,385 ft or 4,384 m altitude), as the image below shows.

Above image further confirms earlier indications that these high methane levels do indeed result from large methane eruptions from the seafloor of the Arctic Ocean.

Greenhouse gas levels in general are very high over the Arctic, as earlier discussed in a recent post and as illustrated by the image below, showing carbon dioxide levels as high as 420 ppm at high latitudes, while the global mean was 403 ppm, on November 19, 2014, p.m., at 945 mb (i.e. 1,916 ft or 584 m altitude).

As said, sustained instances of large abrupt methane eruptions from the seafloor of the Arctic Ocean threaten to strongly accelerate warming in the Arctic even further, in turn resulting in ever more methane being released, as illustrated in the image below, from an earlier post.

Self-reinforcing Feedback Loops

Such methane eruptions are part of a number of self-reinforcing feedback loops that can strongly accelerate warming in the Arctic. Above image, from an earlier post, illustrates two such feedbacks, i.e. albedo changes due to snow and ice demise, and methane releases. Further feedbacks are described in this post and this post, and in the image below.

For a discussion of these and further feedbacks, see this page at the Climate Plan blog 

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.

[ click on image at original post to enlarge ]

IPCC warnings not strong enough



In above paragraph, the IPCC warns about the risk of methane eruptions from the seafloor of the Arctic Ocean further accelerating global warming. While the IPCC does model for a temperature rise that could exceed 12 degrees Celsius in a 'business as usual' scenario (i.e. without action taken), the IPCC does not anticipate that such a rise could occur before the year 2250, as illustrated by the image below.

The situation could be much worse than foreseen by the IPCC, due to a number of reasons, including:

1. The non-linear way feedbacks can hugely increase temperature rises.
2.  The IPCC's underestimation of the amount of methane contained in sediments under the Arctic Ocean and prone to be released as temperatures rise. Shakhova et al. estimate the accumulated methane potential for the Eastern Siberian Arctic Shelf (ESAS) alone as follows:
   - organic carbon in permafrost of about 500 Gt;
   - about 1000 Gt in hydrate deposits; and
   - about 700 Gt in free gas beneath the gas hydrate stability zone.
   Back in 2008, 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.
   Furthermore, mantel methane could add to our predicament, as discussed in an earlier post.
3. Back in 2002, Malcolm Light already warned that seismic events could trigger destabilization of methane hydrates. Furthermore, huge temperature swings can combine with pressure swings and storms, and with swings between expansion and contraction of soil and ice, resulting in severe shocks to ecosystems, as described in an earlier post. 
4. The IPCC's ignoring of large methane eruptions from the seafloor of the Arctic Oceans and the resulting growth of mean global methane levels at higher altitudes, as discussed in an earlier post.

Steven Sherwood et al. wrote back in 2010 that peak heat stress, quantified by wet bulb temperature, across diverse climates today never exceeds 31 degrees Celsius (see also this update). Some may believe that this doesn't apply to the Arctic and the higher altitudes in mountain regions. However, at the June Solstice the amount of solar radiation received in the Arctic is higher than anywhere else on Earth, An increased occurence and intensity of heatwaves could expose large areas of the Arctic and mountain regions to sustained heatwaves exceeding peak heat stress temperatures. In addition, ocean acidification and oxygen depletion in the Arctic Ocean would make it hard for fish, seals, polar bears and further wildlife to survive. Furthermore, the short growth season combined with a long, cold winter limits vegetation in the Arctic, while ecosystems are also becoming increasingly exposed to wild weather swings and wildfires.


Risk Assessment

When taking above points into acount, an absence of action seems to guarantee human extinction by the year 2050. Little action will be ‘too little, too late’ and will merely delay human extinction by a few years, as illustrated by the graph below.

The graph identifies the years 2030 and 2040 as critical. Beyond the year 2030, the risk that humans will go extrinct grows larger than 1% in the absence of action. By the year 2040, the risk of human extinction will have increased substantially, especially if no action will have been taken, but also if too little action will have been taken up to 2040, while even with the best possible programs put in place by the year 2015, there will be a 2% risk of human extinction by 2040, e.g. due to war over what action to take, or due to political opposition or errors making such programs ineffective or even counter-productive.

In conclusion, it is highly likely that the risk of human extinction already now is intolerably high and rising with every moment passing with little or no action taken to reduce the risk. The situation is dire and calls for comprehensive and effective action, as described in the Climate Plan.


Links

• Intergovernmental Panel on Climate Change (IPCC) WGI Fifth Assessment Report (AR5), Final Draft (7 June 2013), page 168.
http://www.climatechange2013.org/images/uploads/WGIAR5_WGI-12Doc2b_FinalDraft_Chapter02.pdf

• Intergovernmental Panel on Climate Change (IPCC) WGI Fifth Assessment Report (AR5), Final Draft (7 June 2013), Figure 12.5.
http://www.climatechange2013.org/images/uploads/WGIAR5_WGI-12Doc2b_FinalDraft_Chapter12.pdf

• An adaptability limit to climate change due to heat stress - by Steven C. Sherwood & Matthew Huber
http://www.pnas.org/content/early/2010/04/26/0913352107.full.pdf

• Ocean Temperature Rise - by Sam Carana
https://arctic-news.blogspot.com/2014/10/ocean-temperature-rise.html

• Methane release from the East Siberian Arctic Shelf and the Potential for Abrupt Climate Change - by Natalia Shakhova & Igor Semiletov
http://symposium2010.serdp-estcp.org/content/download/8914/107496/version/3/file/1A_Shakhova_Final.pdf

• Anomalies of methane in the atmosphere over the East Siberian shelf: Is there any sign of methane leakage from shallow shelf hydrates? - by Shakhova, Semiletov, Salyuk & Kosmach  http://www.cosis.net/abstracts/EGU2008/01526/EGU2008-A-01526.pdf

• Mantle Methane - by Malcolm Light
https://arctic-news.blogspot.com/2014/02/mantle-methane.html

• Evidence linking Arctic amplification to extreme weather in mid-latitudes - by Jennifer A. Francis and S.J. Vavrus, in: Geophysical Research Letters 39 (6):. doi:10.1029/2012GL051000
http://onlinelibrary.wiley.com/doi/10.1029/2012GL051000/abstract

• Near-Term Human Extinction - by Sam Carana
https://arctic-news.blogspot.com/2014/04/near-term-human-extinction.html

• Warm waters threaten to trigger huge methane eruptions from Arctic Ocean seafloor - by Sam Carana
https://arctic-news.blogspot.com/2014/08/warm-waters-threaten-to-trigger-huge-methane-releases-from-arctic-ocean-seafloor.html

• How many deaths could result from failure to act on climate change? - by Sam Carana
https://arctic-news.blogspot.com/2014/05/how-many-deaths-could-result-from-failure-to-act-on-climate-change.html

• Methane linked to Seismic Activity in the Arctic - by Malcolm P. Light & Sam Carana
https://arctic-news.blogspot.com/p/seismic-activity.html

• Wild Weather Swings - by Sam Carana
https://arctic-news.blogspot.com/2014/10/wild-weather-swings.html

• Four Hiroshima bombs a second: how we imagine climate change - by Sam Carana
https://arctic-news.blogspot.com/2013/08/four-hiroshima-bombs-second-how-we-imagine-climate-change.html

• Polar jet stream appears hugely deformed
https://arctic-news.blogspot.com/2012/12/polar-jet-stream-appears-hugely-deformed.html

• Near-Term Human Extinction
https://arctic-news.blogspot.com/2014/04/near-term-human-extinction.html

• Climate Plan
https://arctic-news.blogspot.com/p/climateplan.html

Very warm waters are invading the Arctic Ocean

Global mean methane levels as high as 1836 parts per billion were recorded at several altitudes on August 24, 2014. Meanwhile, the Arctic Ocean continues to warm up. As the image below shows, the ocean heat is felt strongly on the Northern Hemisphere.

Very warm waters from the North Pacific and the North Atlantic Oceans are now invading the Arctic Ocean. Never before in human history have these waters been this warm. In the Arctic Ocean, this is causing very high sea surface temperatures, as shown on the image below.

[ click on image to enlarge ]

The very high temperatures threaten to trigger all kinds of feedbacks, as described in the image below.

Feedbacks in the Arctic

The big danger is that, as the seabed warms up, methane will erupt from hydrates in sediments under the Arctic Ocean. The situation is dire and calls for comprehensiev and effective action, as discussed at the Climate Plan blog.

Post by Sam Carana.