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| [ click on image to enlarge ] |
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| Feedbacks in the Arctic |
Post by Sam Carana.
Tuesday, August 26, 2014
Very warm waters are invading the Arctic Ocean
Tuesday, August 19, 2014
Persistently High Methane Concentrations over Beaufort Sea
High methane concentrations have been showing up over Beaufort Sea over the past few days, as shown on the image below. This follows the recent high methane concentrations over the East Siberian Sea.
The persistent character of these very high methane concentrations over the Arctic Ocean indicates that methane has started to erupt from clathrates under the seabed, triggered by very warm water reaching the bottom of the Arctic Ocean.
Methane eruptions from hydrates in sediments under the Arctic Ocean helped mean methane levels reach new records, with mean global methane readings as high as 1835 parts per billion recorded at several altitudes on August 17, 2014.
The very high sea surface temperature anomalies that show up on above image give an idea of the inflow of warm water from the Pacific Ocean through the Bering Strait. This is further highlighted by the combination image below.
The situation is dire and calls for comprehensive and effective action, as discussed at the Climate Plan blog.
The persistent character of these very high methane concentrations over the Arctic Ocean indicates that methane has started to erupt from clathrates under the seabed, triggered by very warm water reaching the bottom of the Arctic Ocean.
Methane eruptions from hydrates in sediments under the Arctic Ocean helped mean methane levels reach new records, with mean global methane readings as high as 1835 parts per billion recorded at several altitudes on August 17, 2014.
The very high sea surface temperature anomalies that show up on above image give an idea of the inflow of warm water from the Pacific Ocean through the Bering Strait. This is further highlighted by the combination image below.
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| [ click on image to enlarge ] |
Post by Sam Carana.
Friday, August 15, 2014
Heatwave to hit Greenland
A heatwave with temperature anomalies exceeding 36°F (20°C) is expected to hit Greenland between August 16 and 22, 2014, as illustrated by the image on the left and the animation on the right. Such heatwaves can be expected to hit the Arctic more frequently and with greater intensity, as temperatures in the Arctic are rising faster than elsewhere on Earth.
Such heatwaves can result in massive melting on Greenland, as persistent heat changes the texture of the snow and ice cover, in turn reducing its reflectivity. This makes that less sunlight is reflected back into space and is instead absorbed.
Such heatwaves can result in massive melting on Greenland, as persistent heat changes the texture of the snow and ice cover, in turn reducing its reflectivity. This makes that less sunlight is reflected back into space and is instead absorbed.
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| from: Arctic Warming due to Snow and Ice Demise |
As the NSIDC/NOAA graphs below shows, melting on Greenland has been relatively modest this year when compared to the situation in 2012. By July 12, 2012, 97% of the ice sheet surface had thawed, according to this NASA analysis and this NOAA Arctic Report Card.
Melting on Greenland directly affects sea level rise, and melting on Greenland is accelerating due to a number of factors.
Projections of melting on Greenland have long been based on a warming atmosphere only, ignoring the warmer waters that lubricate glaciers and that warm Greenland's bedrock canyons that sit well below sea level.
Furthermore, there are growing quantities of black carbon deposits as a result of burning of fossil fuel and biomass. High temperatures have recently caused ferocious wildfires in Canada that have in turn caused a lot of black carbon to go up high into the atmosphere.
And of course, the atmosphere over the Arctic is warming up much faster than most models had projected. This in turn causes triggers further feebacks, including more extreme weather events such as heatwaves and rain storms that can be expected to hit Greenland with ever more frequency and ferocity. Further feedbacks include methane eruptions from the heights of Greenland, as discussed at the Arctic Feedbacks Page.
When also taking into account the accelerating impact of such factors on melting in Greenland, sea levels could rise much faster than anticipated, as illustrated by the image below.
Melting on Greenland directly affects sea level rise, and melting on Greenland is accelerating due to a number of factors.
Projections of melting on Greenland have long been based on a warming atmosphere only, ignoring the warmer waters that lubricate glaciers and that warm Greenland's bedrock canyons that sit well below sea level.
Furthermore, there are growing quantities of black carbon deposits as a result of burning of fossil fuel and biomass. High temperatures have recently caused ferocious wildfires in Canada that have in turn caused a lot of black carbon to go up high into the atmosphere.
And of course, the atmosphere over the Arctic is warming up much faster than most models had projected. This in turn causes triggers further feebacks, including more extreme weather events such as heatwaves and rain storms that can be expected to hit Greenland with ever more frequency and ferocity. Further feedbacks include methane eruptions from the heights of Greenland, as discussed at the Arctic Feedbacks Page.
When also taking into account the accelerating impact of such factors on melting in Greenland, sea levels could rise much faster than anticipated, as illustrated by the image below.
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| from: more than 2.5m sea level ris |
The image on the right shows a temperature forecast for August 16, 2014, with parts of Greenland changing in color from blue into green, i.e. above the melting point for snow and ice.
Such high temperatures are now hitting locations close to the North Pole ever more frequently, due to the many feedbacks that are accelerating warming in the Arctic, as discussed at this Feedbacks page.
One of the most dangerous feedbacks is a sudden eruption of huge quantities of methane from the seafloor of the Arctic Ocean, as discussed in a recent post.
The impact of such feedbacks can be accumulative and interactive, resulting in self-reinforcing feedbacks loops that can escalate into runaway warming.
Below is another forecast by ClimateReanalyzer for August 16, 2014, showing the remarkable ‘greening’ of Greenland, as well as the very high temperatures reaching the higher latitudes of North America.
Also see the very high sea surface temperatures around Greenland on the image below, created with ClimateReanalyzer.
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| Sea surface temperature anomalies on August 15, 2014. |
Wednesday, August 13, 2014
Horrific Methane Eruptions in East Siberian Sea
A catastrophe of unimaginable propertions is unfolding in the Arctic Ocean. Huge quantities of methane are erupting from the seafloor of the East Siberian Sea and entering the atmosphere over the Arctic Ocean.
As the top image above shows, peak levels as high as 2363 ppb were recorded at an altitude of 19,820 ft (6041 m) on the morning of August 12, 2014. The middle image shows that huge quantities of methane continued to be present over the East Siberian Sea that afternoon, while the bottom image shows that methane levels as high as 2441 ppb were recorded a few days earlier, further indicating that the methane did indeed originate from the seafloor of the East Siberian Sea.
On August 12, 2014, peak methane levels at higher altitudes were even higher than the readings mentioned on above image. Levels as high as 2367 ppb were reached at an altitude of 36,850 ft (11,232 m). Such high levels have become possible as the huge quantities of methane that were released from the seafloor of the Arctic Ocean over the period from October 2013 to March 2014, have meanwhile descended to lower latitudes where they show up at higher altitudes.
Methane eruptions from the Arctic Ocean's seafloor helped push up mean global methane levels to readings as high as 1832 ppb on August 12, 2014.
Ironically, the methane started to erupt just as an international team of scientists from Sweden, Russia and the U.S. (SWERUS-C3), visiting the Arctic Ocean to measure methane, had ended their research.
Örjan Gustafsson describes part of their work: “Using the mid-water sonar, we mapped out an area of several kilometers where bubbles were filling the water column from depths of 200 to 500 m. During the preceding 48 h we have performed station work in two areas on the shallow shelf with depths of 60-70m where we discovered over 100 new methane seep sites.”
Örjan Gustafsson adds that “a tongue of relatively warm Atlantic water, with a core at depths of 200–600 m may have warmed up some in recent years. As this Atlantic water, the last remnants of the Gulf Stream, propagates eastward along the upper slope of the East Siberian margin, our SWERUS-C3 program is hypothesizing that this heating may lead to destabilization of upper portion of the slope methane hydrates.”
Örjan Gustafsson further adds that SWERUS-C3 researchers have on earlier expeditions documented extensive venting of methane from the subsea system to the atmosphere over the East Siberian Arctic Shelf.
In 2010, team members Natalia Shakhova and Igor Semiletov estimated the accumulated methane potential for the Eastern Siberian Arctic Shelf alone to be 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. wrote a paper warning that “we consider release of up to 50 Gt of predicted amount of hydrate storage as highly possible for abrupt release at any time.”
Last year, a team of researchers including Professor Peter Wadhams calculated that such a 50 Gt release would cause global damage with a price-tag of $60 trillion.
As Prof Wadhams explains in the video below: “We really have no choice except to seriously consider the use of geoengineering.”
Sea surface temperatures as high as 18.8°C are now recorded at locations where warm water from the Pacific Ocean is threatening to invade the Arctic Ocean.
At the same time, huge amounts of very warm water are carried into the Arctic Ocean by the Gulf Stream through the North Atlantic. The image below illustrates how the Gulf Stream brings very warm water to the edge of the sea ice.
Waters close to Svalbard reached temperatures as high as 62°F (16.4°C) on July 29, 2014 (green circle). Note that the image below shows sea surface temperatures only. At greater depths (say about 300 m), the Gulf Stream is pushing even warmer water through the Greenland Sea than temperatures at the sea surface.
Since the passage west of Svalbard is rather shallow, a lot of this very warm water comes to the surface at that spot, resulting in an anomaly of 11.1°C. The high sea surface temperatures west of Svalbard thus show that the Gulf Stream can carry very warm water (warmer than 16°C) at greater depths and is pushing this underneath the sea ice north of Svalbard. Similarly, warm water from greater depth comes to the surface where the Gulf Stream pushes it against the west coast of Novaya Zemlya.
As Malcolm Light writes in an earlier post: The West Spitzbergen Current dives under the Arctic ice pack west of Svalbard, continuing as the Yermak Branch (YB on map) into the Nansen Basin, while the Norwegian Current runs along the southern continental shelf of the Arctic Ocean, its hottest core zone at 300 metres depth destabilizing the methane hydrates en route to where the Eurasian Basin meets the Laptev Sea, a region of extreme methane hydrate destabilization and methane emissions.
The images below give an impression of the amount of heat transported into the Arctic Ocean.
The image below gives an idea how methane eruptions from the seafloor of the Arctic Ocean could unfold over the coming decades. For more on this image, see this post and this page.
As said, the situation is dire and calls for comprehensive and effective action, as discussed at the Climate Plan blog at climateplan.blogspot.com and as illustrated by the image below.
As the top image above shows, peak levels as high as 2363 ppb were recorded at an altitude of 19,820 ft (6041 m) on the morning of August 12, 2014. The middle image shows that huge quantities of methane continued to be present over the East Siberian Sea that afternoon, while the bottom image shows that methane levels as high as 2441 ppb were recorded a few days earlier, further indicating that the methane did indeed originate from the seafloor of the East Siberian Sea.
On August 12, 2014, peak methane levels at higher altitudes were even higher than the readings mentioned on above image. Levels as high as 2367 ppb were reached at an altitude of 36,850 ft (11,232 m). Such high levels have become possible as the huge quantities of methane that were released from the seafloor of the Arctic Ocean over the period from October 2013 to March 2014, have meanwhile descended to lower latitudes where they show up at higher altitudes.
Methane eruptions from the Arctic Ocean's seafloor helped push up mean global methane levels to readings as high as 1832 ppb on August 12, 2014.
Ironically, the methane started to erupt just as an international team of scientists from Sweden, Russia and the U.S. (SWERUS-C3), visiting the Arctic Ocean to measure methane, had ended their research.
Örjan Gustafsson describes part of their work: “Using the mid-water sonar, we mapped out an area of several kilometers where bubbles were filling the water column from depths of 200 to 500 m. During the preceding 48 h we have performed station work in two areas on the shallow shelf with depths of 60-70m where we discovered over 100 new methane seep sites.”
Örjan Gustafsson adds that “a tongue of relatively warm Atlantic water, with a core at depths of 200–600 m may have warmed up some in recent years. As this Atlantic water, the last remnants of the Gulf Stream, propagates eastward along the upper slope of the East Siberian margin, our SWERUS-C3 program is hypothesizing that this heating may lead to destabilization of upper portion of the slope methane hydrates.”
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| Schematics of key components of the Arctic climate-cryosphere-carbon system that are addressed by the SWE-C3 Program. a,b) Sonar images of gas plumes in the water column caused by sea floor venting of methane (a: slope west of Svalbard, Westbrook et al., 2009; b: ESAO, Shakhova et al., 2010, Science). c) Coastal erosion of organic-rich Yedoma permafrost, Muostoh Island, SE Laptev Sea. d) multibeam image showing pockmarks from gas venting off the East Siberian shelf. e) distribution of Yedoma permafrost in NE Siberia. f) Atmospheric venting of CH₄, CO₂. (SWERUS-C3) |
In 2010, team members Natalia Shakhova and Igor Semiletov estimated the accumulated methane potential for the Eastern Siberian Arctic Shelf alone to be 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. wrote a paper warning that “we consider release of up to 50 Gt of predicted amount of hydrate storage as highly possible for abrupt release at any time.”
Last year, a team of researchers including Professor Peter Wadhams calculated that such a 50 Gt release would cause global damage with a price-tag of $60 trillion.
As Prof Wadhams explains in the video below: “We really have no choice except to seriously consider the use of geoengineering.”
At the same time, huge amounts of very warm water are carried into the Arctic Ocean by the Gulf Stream through the North Atlantic. The image below illustrates how the Gulf Stream brings very warm water to the edge of the sea ice.
Waters close to Svalbard reached temperatures as high as 62°F (16.4°C) on July 29, 2014 (green circle). Note that the image below shows sea surface temperatures only. At greater depths (say about 300 m), the Gulf Stream is pushing even warmer water through the Greenland Sea than temperatures at the sea surface.
Since the passage west of Svalbard is rather shallow, a lot of this very warm water comes to the surface at that spot, resulting in an anomaly of 11.1°C. The high sea surface temperatures west of Svalbard thus show that the Gulf Stream can carry very warm water (warmer than 16°C) at greater depths and is pushing this underneath the sea ice north of Svalbard. Similarly, warm water from greater depth comes to the surface where the Gulf Stream pushes it against the west coast of Novaya Zemlya.
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| [ click on image to enlarge ] |
The images below give an impression of the amount of heat transported into the Arctic Ocean.
As said, the situation is dire and calls for comprehensive and effective action, as discussed at the Climate Plan blog at climateplan.blogspot.com and as illustrated by the image below.
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