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2/03/2015

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.





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