The Arctic sea ice is steadily decreasing: 2018, 2nd record of melting after 2017 (video)

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The Arctic sea ice is steadily decreasing: 2018, 2nd record of melting after 2017 (video)

The Arctic sea ice is dying, here small icebergs adrift in Greenland
© Christophe Magdelaine / www.notre-planete.info - License: All rights reserved

The Arctic sea ice continued to decline: on March 17, 2018, its maximum extent was only 14.58 million km², the second lowest record in nearly 40 years.

Each year, the sea ice cover over the Arctic Ocean and surrounding seas thickens and spreads during the fall and winter, reaching its annual maximum between late February and early April. Then the ice melts partly in the spring and summer until it reaches its annual minimum in September.

In recent decades, however, Arctic sea ice has declined during the growing and melting seasons, to the point that a record of melt was established on March 7, 2017 with only 13.98 million square kilometers of sea ice. measured by satellite.

While Europe experienced a very cold winter (up to 10 ° C below normal in France), the Arctic experienced particularly high temperatures , 5 to 10 ° C higher than the normals calculated for 2004-2013; the North Pole even experienced temperatures above freezing for a few days in February. As a result, on March 17, 2018 Arctic ice cover reached 14.58 million km², making it the second lowest recorded record.
The 10 records of the lowest Arctic sea ice extent since the 1979 satellite measurements
Data: NCDIS Rank Year In millions of km² Dated
1 2017 14.42 March 7
2 2018 14.48 March 17
3 2015 14.52 February 25
3 2016 14.52 March 24
5 2011 14.67 March 9
5 2006 14.68 12th of March
7 2007 14.77 12th of March
8 2005 14.95 12th of March
8 2014 14.96 March 21st
10 2009 15.17 March 5

March 17, 2018: second record of melting Arctic sea ice.
Credit: NASA Goddard Space Flight Center / Katy Mersmann

" Arctic sea ice coverage continues to decline and this is linked to the continued warming of the Arctic, " said Claire Parkinson , senior climate scientist at NASA's Goddard Space Flight Center in Greenbelt, Maryland. This is a positive feedback loop: " Warming means less ice and more ice will melt, but also, because there is less ice, less incident solar radiation is reflected, which helps to warming, "she adds.

In February 2018, a large open water area appeared in the pack ice in northern Greenland, within the multi-year pack ice - the oldest and thickest ice in the Arctic. While most of it has froze again, it has weakened, and a new opening may appear during the next season of melting. "It could make the ice in this region more mobile and likely to come out of the Arctic this summer, either in the Fram or
Paradoxically, the mass balance of the Greenland ice sheet has been close to normal from September to December 2017, an "exception in the general trend observed over the past two decades, the Greenland ice sheet having lost about 3 600 billion tonnes of ice since 2002, "says WMO. In other words, more than 3 900 billion liters of water have reached the oceans, which is the equivalent of more than 40 times the volume of water in Lake Geneva in Switzerland.

The consequences of melting Arctic sea ice

The consequences of the decline of the Arctic sea ice are numerous and potentially major:

climate and weather changes;
increase in the level of the oceans ;
modification of the ocean circulation with the fear of a sudden cooling in Europe ;
impacts on human communities that depend on ice;
impacts on plants and animals that depend on ice;
modification of navigation routes and opening of new territories for geological and petroleum exploration .

Throughout 2017, the extent of pack ice has been well below normal for the period 1981-2010 in both the Arctic and Antarctic (WMO).

NASA has just launched Operation IceBridge , an aerial flyover of polar ice in the Arctic Ocean to map the distribution and thickness of sea ice. In the fall, NASA will launch a new satellite mission, through the ICESat-2 satellite, which will continuously monitor the evolution of sea ice thickness in the Arctic.

Source: https://www.notre-planete.info/actualites/521-fonte-record-banquise-arctique-2018