Sunday, 1 January 2017

Warming of Arctic Ocean from strong winds

STRONGER WINDS CAUSING FURTHER WARMING OF THE ARCTIC OCEAN



Sam Carana, via Facebook

On December 29, 2016, sea surface temperature was 14.6°C (58.2°F) at a spot near Svalbard.

What causes such a high temperature? The Arctic Ocean is warming due to the inflow of warm water from the Atlantic Ocean. Stronger winds are pushing warm water from the North Atlantic into the Arctic Ocean. Why are these winds getting stronger? As the Arctic warms faster than the rest of the world, the temperature difference between the Arctic and the Equator decreases, making the Jet Stream wavier, with longer loops extending to the north and to the south. At the same time, the temperature difference between the oceans and the continents (Europe, Asia and North America) is increasing, speeding up the Jet Stream as it travels, e.g., over the North Atlantic towards the Arctic Ocean.

Indeed, the 14.6°C sea surface temperature on December 29, 2016, near Svalbard is the result of warm water getting pushed from the North Atlantic into the Arctic Ocean. Underneath the surface of the North Atlantic, the water is much warmer than at the surface, and this temperature difference increases as winds get stronger and cause stronger evaporation, which has a cooling effect on the sea surface. As described in earlier posts, a cold freshwater lid on the North Atlantic could result from stronger evaporation, in combination with meltwater, causing more heat to get carried into the Arctic Ocean underneath the sea surface, due to reduced heat transfer to the atmosphere from water on its way to the Arctic Ocean.

The situation looks set to continue and get worse. The combination image in the post shows that the Jet stream is forecast to reach speeds as high as 319 km/h or 198 mph in between North America and Greenland on December 31, 2016 (left panel). At the same time, surface winds are forecasts to reach speeds as high as 95 km/h or 59 mph (center panel) and waves as high as 8.96 m or 29.4 ft in between Norway and Svalbard (right panel). The situation is further illustrated by the video that shows winds over the North Atlantic from December 27, 2016 to January 3, 2017, with forecasts by cci-reanalyzer.org.
https://www.youtube.com/watch?v=V0jkxhODVQY


The fact that this is not a one-off event is also illustrated by the 2015 image showing the Jet Stream reaching speeds of 384 km/h or 239 mph over the Pacific Ocean on December 27, 2015. At the same day and time in 2015, the Jet Stream reached speeds as high as 430 km/h or 267 mph as it moved over North America on its way over the North Atlantic.

In conclusion, increasingly stronger winds are causing huge amounts of heat to enter the Arctic Ocean from the North Atlantic, and also from the Pacific Ocean. As the water of the Arctic Ocean keeps warming, the danger increases that methane hydrates at the bottom of the Arctic Ocean will destabilize.
From the post 'Accelerating Warming of the Arctic Ocean', at:
http://arctic-news.blogspot.com/…/accelerating-warming-of-t…




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