Ocean Heat Overwhelming North Atlantic

Arctic sea ice extent on June 16, 2016, was at a record low for the time of the year.

[ image from JAXA ]

Sea surface temperature near Svalbard was as high as 55°F (or 12.8°C, at the green circle) on June 14, 2016, an anomaly of 19.6 °F (or 10.9°C) from 1981-2011, as illustrated by the image below.

[ click on images to enlarge ]

Above image further shows that the cold lid that had been growing so prominently in extent over the North Atlantic over the past few years, has shrunk substantially. By comparison, the cold area over the North Pacific has grown larger.

Plenty of meltwater has run off from Greenland in 2016, as illustrated by the NSIDC.gov image on the right. The run-off from Alaska and Siberia into the Pacific seems less by comparison than the run-off into the North Atlantic. So, how could it be that the cold area in the North Pacific has grown larger than the cold area in the North Atlantic?

The image below gives another comparison, between June 1, 2015 (top), and June 1, 2016 (bottom), showing anomalies from 1961-1990.

The difference is striking, especially when considering the strength of the colder anomalies (from 1961-1990). Besides meltwater, something else must be influencing the size and strength of these anomalies in the North Atlantic and the North Pacific in different ways. Quite likely, the difference is caused by the Global Ocean Conveyor Belt (or thermohaline circulation), which is carrying warm water into the North Atlantic, while carrying cold water out of the North Atlantic. In the North Pacific, it is doing the opposite, i.e. carrying cold water in, while carrying warm water out of the North Pacific.

[ Note that this animation is a 2.3 MB file that make take some time to fully load ]

In conclusion, there are several issues that are influencing the situation, including the influence El Niño has had and the impact La Niña will have. Even if the Conveyor Belt may slow down, more important than its speed is how much heat it will carry into Arctic Ocean. The image below shows a trend pointing at the water on the Northern Hemisphere getting 2 degrees Celsius warmer well before the year 2030, compared to the 20th century average.

If such trends continue or even strengthen, ever warmer water will be carried from the North Atlantic into the Arctic Ocean. Since the Atlantic inflow is about 10 times greater in volume than the Pacific inflow, this will further speed up warming of the Arctic Ocean.

A warmer Arctic Ocean will speed up decline of the sea ice, causing more sunlight to be absorbed by the Arctic Ocean, as one of the feedbacks that are further accelerating warming of the Arctic Ocean. The danger is that heat will reach the seafloor and will destabilize methane hydrates contained in sediments at the seafloor of the Arctic Ocean.

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


Links

- NASA Study Finds Atlantic 'Conveyor Belt' Not Slowing (March 25, 2010)
http://ift.tt/K3c3ZPnews.php?release=2010-101

- Arctic Ocean Circulation: Going Around At the Top Of the World, by Rebecca Woodgate (2013) http://ift.tt/I7PO3U

- Feedbacks
http://ift.tt/1JO7GM6

- Climate Plan
http://ift.tt/1XoCgDS

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