Saturday, 20 August 2016

The storm over the Arctic

Storms over Arctic Ocean

19 August, 2016

Winds over the Arctic Ocean reached speeds of up to 32 mph or 52 km/h on August 19, 2016. The image below shows the Jet Stream crossing Arctic Ocean on August 19, 2016 (see map on above image for geographic reference).

The Naval Research Lab image on the right shows a forecast for sea ice speed and drift run on August 15, 2016, and valid for August 17, 2016.

These storms come at a time when the sea ice has become extremely thin, as illustrated by the Naval Research Lab sea ice thickness animation below, covering a 30-day period run on August 17, 2016, with a forecast through to August 25, 2016. The animation shows that the multi-year sea ice has now virtually disappeared.

With the sea ice in such a bad shape, strong winds can cause a rapid drop in sea ice extent, at a time when the Arctic still has quite a bit of insolation. At the North Pole, insolation will come down to zero at the time of the September 2016 Equinox.

Even more terryfying is the Naval Research Lab's Arctic sea ice thickness forecast for August 25, 2016, run on August 17, 2016, using a new Hycom model, as shown on the right.

With the thicker multi-year sea ice virtually gone, the remaining sea ice is prone to fracture and to become slushy, which also makes it darker in color and thus prone to absorb more sunlight.

Furthermore, if strong winds keep hitting the Arctic Ocean over the next few weeks, this could push much of the sea ice out of the Arctic Ocean, along the edges of Greenland and into the Atlantic Ocean.

Strong winds are forecast to keep hitting the Arctic Ocean hard for the next week, as illustrated by the image on the right showing a forecast for August 24, 2016.
As sea ice extent falls, less sunlight gets reflected back into space and is instead absorbed by the Arctic. Once the sea ice is gone, this can contribute to a rapid rise in temperature of the surface waters. 

The image below shows sea surface temperature anomalies in the Arctic (latitude 60°N-90°N) compared to 1961-1990.

The Climate Reanalyzer image below also shows sea surface temperature anomalies August 16, 2016, this time compared to 1979-2000.

The image below, from an 
earlier post, shows sea surface temperature anomalies on August 12, 2016, in the left-hand panel, and sea surface temperature anomalies in the righ-hand panel.
Sea surface temperature and anomaly. Anomalies from +1 to +2 degrees C are red, above that they turn yellow and white

Above image also shows that on August 12, 2016, sea surface temperatures near Svalbard (at the location marked by the green circle) were as high as 18.9°C or 65.9°F, an anomaly of 13.6°C or 24.4°F.

Where seas are shallow, a surface temperature rise can quickly warm up water all the way down to the Arctic ocean seafloor, where it can destabilize methane hydrates contained in sediments.

This could make that huge amounts of methane get released from the seafloor. Given that many of the seas in Arctic are very shallow, much of this methane can enter the atmosphere without getting broken down in the water, resulting in huge additional warming, especially over the Arctic. As discussed in an 
earlier post, this could contribute to a global temperature rise of over 10°C or 18°F by the year 2026.

One of the people who has been warning about these dangers for many years is Professor Peter Wadhams, whose new book 
A Farewell to Ice was recently launched (256 pages, published September 1, 2016).

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

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