At the moment, a large part of Russia is experiencing temperature anomalies at the highest end of the scale, i.e. more than 36°F (20°C) warmer than average past records.
Above image shows the situation as at March 20, 2014. The image below is a forecast for March 22, 2014.
Over the past year, average temperatures over the Arctic Ocean have been much higher than they used to be, as illustrated by the NOAA image below.
Warming in the Arctic is accelerating, in part due to a number of feedbacks such as extreme weather. Temperatures over the Arctic Ocean are expected to rise even further next week. The Arctic as a whole is expected to reach average anomalies as high as 5.3°C next week, while many areas over the Arctic Ocean are expected to be hit by even higher anomalies, as the image below shows.
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| [ click on image to enlarge ] |
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As above image illustrates, temperatures over a large part of North America can be expected to be hardly higher than temperatures over the Arctic Ocean mid next week. It is this very difference between high altitude temperatures and lower altitude temperatures that drives the Jet Stream. In the absence of much difference, changes to the Jet Stream are making it easier for cold air to move out of the Arctic and for warm air from lower latitudes to move in. The Polar Vortex is similarly affected, as illustrated by the image below.
At lower altitude, the highest wind speed detected on the image below was 94 km/h (green marker). Strong winds brought a lot of rain from the Atlantic Ocean to the U.K., as has been the case for some time.
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| [ click on image to enlarge ] |
The result is more extreme weather, which can translate into more intense storms, heatwaves, droughts, wildfires and further havoc. Importantly, storms across the Arctic Ocean and higher wind speeds along the edges of Greenland can break up the ice and speed up its exit from the Arctic Ocean. The Naval Research Laboratory animation below shows strong winds pushing the sea ice around and speeding up its exit along the edges of Greenland.
Despite the cold weather that has hit large parts of North America over the past few months, the water off the coast of North America has not cooled, as illustrated by the image below. The blue and lilac colored areas are in part the result of exit currents carrying cold water out of the Arctic Ocean more rapidly, while the Gulf Stream continues to carry warmer water (brown and red colored areas) into the Arctic Ocean.
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| [ Sea Surface Temperatures (SST) - click on image to enlarge ] |
The Arctic is especially vulnerable to warming, due to a number of circumstances, including:
- Gulf Stream carrying warmer water into the Arctic Ocean;
- Arctic snow and ice cover is at the verge of collapse;
- Methane is present in large quantities under the seafloor of the Arctic Ocean.
These circumstances and the combined impact of feedbacks such as extreme weather make that, on top of global warming, the Arctic is hit by a second, addtional kind of warming, i.e. accelerating warming in the Arctic.
The joint impact of feedbacks is becoming stronger, as temperatures keep rising in the Arctic and with continued demise of the snow and ice cover. So, let's start with feedback #1, i.e. that, as snow and ice cover decline further, an ever larger part of the sunlight will be absorbed by the Arctic Ocean, rather than to (a) be reflected back into space or (b) be consumed in the process of transforming ice into water. This first feedback will then be amplified by further feedbacks such as storms that can more easily develop in open water. And, as the weather becomes more extreme, stronger storms and heatwaves can be expected to hit the Arctic Ocean, causing further demise of the sea ice, resulting in more heat being absorbed by the Arctic Ocean. Thus, feedbacks can amplify each other, causing warming in the Arctic to accelerate even further.
- Gulf Stream carrying warmer water into the Arctic Ocean;
- Arctic snow and ice cover is at the verge of collapse;
- Methane is present in large quantities under the seafloor of the Arctic Ocean.
These circumstances and the combined impact of feedbacks such as extreme weather make that, on top of global warming, the Arctic is hit by a second, addtional kind of warming, i.e. accelerating warming in the Arctic.
The joint impact of feedbacks is becoming stronger, as temperatures keep rising in the Arctic and with continued demise of the snow and ice cover. So, let's start with feedback #1, i.e. that, as snow and ice cover decline further, an ever larger part of the sunlight will be absorbed by the Arctic Ocean, rather than to (a) be reflected back into space or (b) be consumed in the process of transforming ice into water. This first feedback will then be amplified by further feedbacks such as storms that can more easily develop in open water. And, as the weather becomes more extreme, stronger storms and heatwaves can be expected to hit the Arctic Ocean, causing further demise of the sea ice, resulting in more heat being absorbed by the Arctic Ocean. Thus, feedbacks can amplify each other, causing warming in the Arctic to accelerate even further.
One of the most dangerous feedbacks is that, as the Arctic Ocean warms up further and as the Gulf Stream carries ever warmer water into the Arctic Ocean, methane can erupt from the seafloor of the Arctic Ocean in large quantities. Methane eruptions from the seafloor of the Arctic Ocean have become especially noticable over the past half year. The big danger is that this will develop into a third kind of warming, runaway global warming.
Large amounts of methane are still entering the atmosphere over the Arctic Ocean, which contains very little hydroxyl to start with, so large abrupt releases will deplete the little hydroxyl that is there much faster than elsewhere. Furthermore, the methane will initially be highly concentrated in the atmosphere over the Arctic Ocean, and where the methane does move out of the Arctic, it could warm up the water along the track of the Gulf Stream, causing even warmer water to enter the Arctic Ocean. For years after its release, the methane will act as a powerful greenhouse gas. Unlike the albedo changes, which have the highest impact at the June Solstice when the amount of solar radiation received by the Arctic is higher than anywhere else on Earth, methane prevents heat from radiating out into space throughout the year.
The interactive diagram below gives an overview of these three kinds of warming and the numerous feedbacks that are accelerating warming in the Arctic, from the earlier post The Biggest Story of 2013.
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| Hover over each kind of warming and feedback to view more details, click to go to page with further background |
In conclusion, the situation is dire and calls for comprehensive and effective action, as described at the Climate Plan blog.
Related
- The Biggest Story of 2013
http://arctic-news.blogspot.com/2013/12/the-biggest-story-of-2013.html
- Climate Plan
http://climateplan.blogspot.com
- Changes to Polar Vortex affect mile-deep ocean circulation patterns
http://arctic-news.blogspot.com/2012/09/changes-to-polar-vortex-affect-mile-deep-ocean-circulation-patterns.html
- Diagram of Doom
http://arctic-news.blogspot.com/2012/08/diagram-of-doom.html
- Polar Jet Stream appears hugely deformed
http://arctic-news.blogspot.com/2012/12/polar-jet-stream-appears-hugely-deformed.html
- Methane Levels going through the Roof
http://arctic-news.blogspot.com/2013/11/methane-levels-going-through-the-roof.html
- Ocean heat: Four Hiroshima bombs a second: how we imagine climate change
http://arctic-news.blogspot.com/2013/08/four-hiroshima-bombs-second-how-we-imagine-climate-change.html
- (Three kinds of) Warming in the Arctic
http://arctic-news.blogspot.com/p/warming-in-arctic.html
- Snow and ice decline causing more sunlight to be absorbed by the Arctic Ocean
http://arctic-news.blogspot.com/2012/07/albedo-change-in-arctic.html - Methane releases warming up Arctic air
http://arctic-news.blogspot.com/2013/11/methane-levels-going-through-the-roof.html - As sea ice decline weakens vertical currents, seabed warms
http://arctic-news.blogspot.com/2012/09/arctic-sea-ice-loss-is-effectively-doubling-mankinds-contribution-to-global-warming.html - Storms cause vertical mixing of water
http://arctic-news.blogspot.com/2012/07/arctic-waters-are-heating-up.html - Accelerated Arctic warming causes storms that push cold air of the Arctic
http://arctic-news.blogspot.com/2012/08/diagram-of-doom.html - Extreme weather causing storms that push away sea ice
http://arctic-news.blogspot.com/2012/04/supplementary-evidence-by-prof-peter.html - Extreme weather causing storms that create higher waves, breaking up the sea ice
http://arctic-news.blogspot.com/2012/08/huge-cyclone-batters-arctic-sea-ice.html - Storms creating more wavy waters that absorb more sunlight
http://arctic-news.blogspot.com/2012/08/diagram-of-doom.html - Extreme weather causing fires, etc.
http://arctic-news.blogspot.com/2012/07/how-extreme-will-it-get.html - Weaker polar vortex and jet stream let cold air move out of Arctic
http://arctic-news.blogspot.com/2012/08/opening-further-doorways-to-doom.html - Extreme weather causing warmer waters
http://arctic-news.blogspot.com/2013/12/the-biggest-story-of-2013.html - Snow and ice decline cause seismic activity that destabilizes hydrates
http://arctic-news.blogspot.com/2013/09/methane-release-caused-by-earthquakes.html - Methane releases prevent sea ice from forming
http://arctic-news.blogspot.com/2013/12/methane-emerges-from-warmer-areas.html
Post by Sam Carana.
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