Arctic Ice Extent Tops 2012's, But Is 6th Lowest In History

We mentioned recently the rebound in Arctic ice levels compared to those found at the end of last summer; now that the 2013 minimum has been reached, Forbes' Alex Knapp points out that 2013's figures still show the 6th lowest ice extent in recorded history. "This pattern is expected to continue as average global temperatures continue to rise, leading to further Arctic Ice melts. The volume of sea ice – that is, how thick the Arctic ice is, has also been steadily declining over the same period. And although the charts above only go back to the 80s, the loss of sea ice began several decades prior to that. In 2011, a paper published in Nature estimating Arctic ice extent for the past 1450 years shows a sharp decline in Arctic ice beginning in the mid-20th century."

Comments

history?

[iggymanz]

Reliable monitoring with authoritative of sea ice extents began only with the Scanning Multichannel Microwave Radiometer (SMMR) on the satellite Seasat launched June 28, 1978.

Very spotty records before that time are not considered reliable.

Re:history?

[haruchai]

The Danes have excellent records going back to the '30s.
And let's not forget that the volume is also dropping precipitously but that's much more difficult to measure.

Re:history?

[I'm New Around Here]

So where were they when it was warm enough that the Vikings had two separate colonies on the southern shores of Greenland? Or was Canada still frozen while Greenland was basking in warmth?

Re:history?

[Mashiki]

Yeah...you might just want to stop trotting out the "threatened status with ice" bit. There's no shortage of the bloody things, if anything there are more every passing year and their range of liveable area keeps expanding. In fact, there have been more than a few clashes between brown and polar bears in the last few years. As a fun point, we have them here in Ontario, and not all that far outside of the "southern half" of the province. And they range south, even in the summer here. There have been warnings posted as far south as Kesagami Provincial Park.

Re:history?

[I'm New Around Here]

They failed after being there for 500 years. The first 400 must have been warm enough to keep them there and in good health.

It was only later that the climate cooled, and they were forced to change their lifestyle, and finally leave Greenland.

So my point stands: When it was that warm in Greenland, it was certainly warm in Canada and Alaska. So where did the polar bears live, if warmer water is lethal to them?

.
PS. This article says the Vikings actually adapted to the colder climate, and ate more seal meat as their livestock dwindled over the colder years. They only left in the end because they couldn't trade for needed materials anymore.
http://www.spiegel.de/international/zeitgeist/archaeologists-uncover-clues-to-why-vikings-abandoned-greenland-a-876626.html

Re:So who said...

[Anonymous Coward]

Scientists.
This source is dated 1960.
New Scientist.
The year 2000.

http://books.google.ca/books?id=yJjFw4bzRi0C&pg=PA1453&dq=global+warming&hl=en&ei=_vZbTfq4F5OCsQPI5vyxCg&sa=X&oi=book_result&ct=result&redir_esc=y#v=onepage&q&f=false

Re:why should anybody care?

[sycodon]

This week, after reviewing his own new data, NASA climate scientist Jay Zwally said: "At this rate, the Arctic Ocean could be nearly ice-free at the end of summer by 2012, much faster than previous predictions."

Too fucking easy.