[NeroASERCH]

Prior to 2010, there was probably no time since the 12th century in which circumnavigation of the north pole was possible.
Each year since then, the Northwest and Northeast passage have both cleared. It was first clear this year on 9 August, compared to 19 August last year.

There was a big chunk north of Siberia for a while that wouldn't budge. A few days ago it looked rather amusingly like an angry ghost:
http://www.dazvoz.com/nsidc-ice-extent-05-08-2012.png

But the polynya representing the ghost's mouth thwackened out like a beauty and his whole head came off.

[Ifroham4]

thwackened.. that one goes in my book.

[Ifroham4]

http://nsidc.org/data/masie/

[LottiFurmann]

But did the Artic passages freeze just as well as they have done previously?

[Paul Bunyan]

But did the Artic passages freeze just as well as they have done previously? The Arctic ice is melting because of the hot ocean. Old ice is disappearing very fast

[HedgeYourBets]

The reduction of the summer sea ice was first recorded in the Barents Sea and in the Kara Sea to the west, and later spread to more eastern parts of the Northeast Passage. From the end of August 1940 - shortly after the passage of the German auxiliary cruiser Komet - to the end of September the entire Northeast Passage was reported free of ice (Ahlman 1947, p.305). No less than about 100 ships were operating along the USSR arctic coast during this period. Relatively warm conditions existed in large parts of the Arctic August-September 1940.
Mapping of the sea ice along the USSR arctic coast from airplanes demonstrated that the summer sea ice extent from 1924 to 1944 decreased about 1 mill. km2 within the USSR part of the Arctic (Ahlmann 1947).

In addition, along the route taken by the drifting Norwegian research vessel Fram across the Arctic Ocean 1893-1896, the average sea ice thickness of first year sea ice has decreased from 365 cm as recorded by Fram, to only 218 cm as recorded by the USSR icebreaker Sedowduring its drift 1937-1940, roughly following the route of Fram 1893-1896 (Ahlman 1947).
Finally, Ahlmann (1947) draws attention to coastal erosion in the USSR part of the Arctic. A couple of Siberian islands consisting of ice-rich permafrost have melted completely away because of the warming, and the southern border of permafrost in Russia and Siberia has retreated towards north by several 10 km's.


Builtfor the Royal Canadian Mounted Police Force to serve as a supply ship forisolated, far-flung Arctic RCMP detachments, St. Roch (323 tons) was also designed to servewhen frozen-in for the winter as a floating detachment with its constablesmounting dog sled patrols from the ship. Between 1929 and 1939St. Roch made three voyages to the Arctic.Between 1940 and 1942St. Roch navigated the Northwest Passage, arriving in Halifax harbor on October11, 1942.

St . Roch was thereby the second ship to make the passage, and thefirst to travel the passage from west to east. In 1944,St. Roch returned to Vancouvervia the more northerly route of the Northwest Passage,making her run in 86 days. The epic voyages of St. Roch demonstrated Canadiansovereignty in the Arctic during the difficult wartime years, and extendedCanadian control over its vast northern territories.
Retired after returning from the Arctic in 1948,St. Roch was sent to Halifaxby way of the Panama Canal in 1950. Thisvoyage made St. Roch the first ship to circumnavigate North America.



Diagram showing the average frontal retreat of 10-15 outlet glaciers from Jostedalsbreen in southern Norway (Ahlman 1947). Photo showing the terminus of the outlet glacier Mjölkevoldsbreen taken by J. Rekstad 1900 (Figure 3a in Ahlman 1947).





Photos showing the terminus of the outlet glacier Mjölkevoldsbreen taken by K. Fægri in August 1937 (left) and 19 July 1946 (right). Reproduced from figure 3b and 3c in Ahlmann 1947.


http://www.climate4you.com/ClimateAn...01900-1949.htm

[Raj_Copi_Jin]

The Arctic Ocean is warming up, icebergs are growing scarcer and in some places
the seals are finding the water too hot, according to a report to the Commerce
Department yesterday from Consulafft, at Bergen , Norway.
Reports from fishermen, seal hunters, and explorers all point to a radical change in
climate conditions and hitherto unheard-of temperatures in the Arctic zone.
Exploration expeditions report that scarcely any ice has been met as far north as
81 degrees 29 minutes.

Soundings to a depth of 3,100 meters showed the gulf stream still very warm.
Great masses of ice have been replaced by moraines of earth and stones, the
report continued, while at many points well known glaciers have entirely disappeared.

Very few seals and no white fish are found in the eastern Arctic, while vast shoals
of herring and smelts which have never before ventured so far north, are being
encountered in the old seal fishing grounds. Within a few years it is predicted
that due to the ice melt the sea will rise and make most coastal cities uninhabitable.

The Washington Post
November 2, 1922

[Fegasderty]

The Arctic ice is melting because of the hot ocean. Old ice is disappearing very fast

[doctorzlo]

Zeppelin
you are a great source... THANKS !!!

[Ifroham4]

Observer, you giant doofus... that news item indicates only _one_ of the passages was open.

In order to circumnavigate the pole, you need both the NE passage and the NW passage open (as has occurred in the last three years, and at no other time since the Dark Ages.)

[Fegasderty]

Observer, you giant doofus... that news item indicates only _one_ of the passages was open.

In order to circumnavigate the pole, you need both the NE passage and the NW passage open (as has occurred in the last three years, and at no other time since the Dark Ages.)

============
Not if you have a submarine sitting in the garage...

[Drugmachine]

Observer, you giant doofus...
Could you please insert a smiley face, at the least, when calling me a "giant doofus" dv ?


that news item indicates only _one_ of the passages was open.

In order to circumnavigate the pole, you need both the NE passage and the NW passage open (as has occurred in the last three years, and at no other time since the Dark Ages.)
Lets take a closer look, dv, at my "news item".


From the end of August 1940 - shortly after the passage of the German auxiliary cruiser Komet - to the end of September the entire Northeast Passage was reported free of ice (Ahlman 1947, p.305).

Mapping of the sea ice along the USSR arctic coast from airplanes demonstrated that the summer sea ice extent from 1924 to 1944 decreased about 1 mill. km2 within the USSR part of the Arctic (Ahlmann 1947).

Roch made three voyages to the Arctic.Between 1940 and 1942. Roch navigated the Northwest Passage, arriving in Halifax harbor on October11, 1942.


I believe that this info indicates that the NE & NW passages were both ice free between 1940 to 1944.

[softy54534]

I believe that this info indicates that the NE & NW passages were both ice free between 1940 to 1944. You believe wrongly with typical wiful interpretation of material.

The only explicit reference to ice-free conditions in your reports is for the NE Passage for one whole month in September 1940.

You have a note about the (second ever) crossing of the NW Passage by the St Roch between 1940 and 1942. Please note that the St Roch was breaking ice the whole way through its 2.5 year journey, and was frozen in over the two winters of this voyage. The passage most certainly was not "ice free" in this time.
http://www.ucalgary.ca/arcticexpedit...senexpeditions

[radikal]

So, what were the ice conditions like in the North West Passage in mid-late 1940?

The year 1940 was bad for heavy ice, with prevailing northerly and north-westerly winds, and we were continually beset. It took us from July 23 to August 12 to make the 400 miles between Point Barrow and Herschel Island. Sometimes there was not a drop of water in sight as the ice packed itself tightly round us. At other times we were free to move about in little pools from which there was no outlet. At all times we had to be on the move to avoid damage, often moving only a shiplength or two. Sometimes we used "black gunpowder" to crack particularly nasty floes threatening our rudder and propeller. Henry A. Larsen, The Conquest of the North West Passage: The Arctic Voyages of the St. Roch, 1940-44

[radikal]

Just so that deevs doesn't have it all his own way though I note that he was wrong. The North Pole was circumnavigated in 2008 by the Polarstern. Of course it was an icebreaker but he didn't mention anything about that. In any case at least some people claim that both passages were ice free in August 2008.

http://idw-online.de/pages/de/news284090

[MannoFr]

In previous threads on this topic I've added "except in an icebreaker or submarine" ...

But you're right, the Uni of Bremen people also reckon it was clear in 2008. Consider me chastened.

BTW ... it certainly seems that 2012 will break the record for lowest amount of Arctic sea Ice (during the satellite era) in the next few days, with two or maybe three weeks of melt left to come.

[Paul Bunyan]

Although no announcement has been made by NSIDC, the 25 Aug graph indicates that the previous record low in Arctic ice has been reached.

[Raj_Copi_Jin]

In previous threads on this topic I've added "except in an icebreaker or submarine" ... Can't let your guard down for a moment around here.

[Drugmachine]

Can't let your guard down for a moment around here.

[radikal]

Once again I can see a face up there, this time in profile.

[IMG]dazvoz.com/nsidc-25aug2012.jpg[/IMG]