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Northwest passage now ice free and easier to traverse

What the science says...

Select a level... Basic Intermediate

Anyone relying on the fact that the Northwest Passage was navigated in the 1940s, to claim that the Passage obviously must have been ice-free then (as it is more regularly now), is not being truly sceptical, but is relying on half-truths to confirm a pre-conceived belief. If you read the original sources, a very different picture reveals itself.

Climate Myth...

Northwest passage has been navigated in the past

"Here is a photo of the St. Roch. It’s a wooden ship, not some massive, metallic icebreaker. According to the Vancouver Maritime Museum web site, this 104 foot wooden ship sailed through the Northwest Passage from 1940 to 1942, that was from west to east. In 1944 it did it again from from east to west...Once “global warming” is mentioned all critical faculties are shut down in the media. They don’t verify facts. They just repeat the claims that are made" (Classically Liberal)

These are the basic details, from the original account given in the sources listed at the end.

The first voyage through the Northwest Passage by the 'St. Roch' took about 28 months (850 days), between June 23 1940 and Oct 11 1942. The voyage itself certainly wasn't meant as a non-stop attempt, because they had duties to perform as a Royal Canadian Mounted Police ship, but it did get frozen in on two occasions (from mid/late September to July/Aug 1940 and 1941), and the description of the journey refers often to heavy, packed ice and a scarcity of consistent open water - as well as the use of gunpowder to create breaks in the ice. In fact, the overall description of the conditions experienced during the journey (given by Henry Larsen, the Captain of the boat, in his autobiography - see below) reveals how bad it was :

 "The three seasons of the short Arctic Summers from 1940-42 had been extremely bad for navigation, the worst consecutive three I had experienced as far as ice and weather conditions were concerned, and in my remaining years in the Arctic I never saw their like. Without hesitation I would say that most ships encountering the conditions we faced would have failed. I also believe that had we missed the single opportunity we had to get out of Pasley Bay, we most certainly would still be there, in small bits and pieces."

So, not ice-free at all.

The second journey took a total of 86 days (from July 22 to Oct 16 1944), although it actually involved 43 days of actual sailing. That certainly sounds like it was more straightforward and sounds like it may have involved steaming through an ice-free Passage, doesn't it ? Well, the reality is rather different. The description again is of heavy, tightly-packed ice and atrocious weather - so much so that the only really fine day was actually noted in the account. Again, most of the open water they experienced consisted of leads between the ice, which they had to follow as far as they could before anchoring on the ice to shelter from the persistently bad weather. It was reported by Larsen that that particular season was "the worst in years."

Again, hardly ice-free by any description.

In fact, as Larsen himself later acknowledged, the only reason the voyages were attempted had nothing to do with any widespread opening-up of the Passage and everything to do with WWII and Canada's determination to re-iterate its sovereignty over the Northwest Passage, and its concern to show that there were no physical obstacles to prevent it defending its territory.

Compare those voyages above with more recent ones : such as the 'St. Roch II' catamaran, which did the journey in 2000 in three weeks and encountered very little ice; the 'Cloud Nine' ketch, which completed the journey in 45 days in 2007, encountering "hardly any ice"; the 'Babouche', which completed the journey completely by sail for the first time; the Rigid Inflatable Boat (RIB) which completed the journey in two weeks in 2010; and the yacht and trimaran which traversed both the Northwest and Northeast Passages in one season. You can even take a cruise along those waters these days, if you fancy it.

And compare those 1940s conditions with those more usual now : such as 2007, when the Northwest Passage demonstrably opened up for the first time officially recorded; 2008, when both the Northwest and Northeast Passages demonstrably both opened up at the same time for the first time officially recorded; 2010 and 2011, when the Northwest Passage was officially open again. Have a look at the satellite pictures here and here to see what it looks like.

All in all, the Northwest Passage has most definitely been open and ice-free in recent years (and is now more regularly open and navigable); and there is no proof whatsoever that it was ice-free back in the 40s (or, indeed, in any other recent period) - but definitely wasn't open and ice-free when the 'St. Roch' made its difficult transits.


**The Conquest of the North West Passage : The Arctic Voyages of the St. Roch, 1940-44 – Inspector Henry A. Larsen, R.C.M.P.                                                      The Geographical Journal, Vol CX Nos 1-3, July – September 1947                            (The first page is accessible for free at :

**The North-West Passage, 1940-42 and 1944 : The Famous Voyages of the Royal Canadian Mounted Police Schooner “St. Roch”
Sergeant Henry Larsen, F.R.G.S., Commander Edmond Cloutier, C.M.G., 1958

**The Big Ship : An Autobiography by Henry A. Larsen, in co-operation with Frank R. Sheer and Edward Omholt-Jensen, 1967

Last updated on 5 October 2011 by JMurphy. View Archives

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Comments 1 to 8:

  1. WOW First class post! Thank you for that information
  2. JMurphy: The Voyage of 1944 was not quite as difficult as you maintain. Capt Larsen was a skilled Captain. At times there was heavy ice, at times there was no ice to be seen. To have accomplished this without the benifit of satillite images is really a feat in and off itself.
  3. Camburn, I have never called into question the skills of Capt. Larsen (in fact I praise him and his crew), but his own words (as given above) speak volumes : ...“It was really the only fine day we had during the entire passage...” (2) “...season was the worst in years.” (1) (2) Read the references given if you can.
  4. Camburn elsewhere maintains that the N-W Passage was significantly warmer than current for long periods of the Holocene, citing as evidence Bow Head whale skeletons. My understanding is that bow head whale skeletons can be found across the length of the North West Passage during a period the preceding the Holocene Climactic Optimum:
    "The distribution and radiocarbon ages of whale remains indicate that during at least one interval of the Holocene, Bering Sea and Davis Strait bowheads could intermingle, (Figure 1b). The Bering Sea bowhead was the first to reach the CAA about 10,000 carbon-14 (14 C) years ago (11,450 calendar years B.P.). Bowheads entered via the Beaufort Sea about 1000 years after submergence of the Bering Strait, and they ranged up to the fronts of receding continental ice sheets [Dyke et al., 1996; Dyke and Savelle, 2001]. Until about 9500 14 C years B.P. (10,700 calendar years B.P.), by which time the Davis Strait bowhead ranged into the eastern Northwest Passage, the Bering Sea and Davis Strait stocks were separated by a glacier ice barrier. With dissipation of this barrier, the two stocks were able to intermingle, ranging well beyond historical limits. About 8000 14 C years B.P. (8900 calendar years B.P.), the Bering Sea and Davis Strait stocks were separated, as they are today. Thus, a year-round sea ice barrier must have become established at that time in the central part of the Northwest Passage."
    (Fisher et al, 2006, my emphasis) In other words the NW Passage was open only for 1,800 year interval ending approx 9,000 years ago and there has been no skeletal evidence since for the intermingling of Atlantic and Pacific Bowheads. That strongly suggests any opening of the straits since then has been brief, and intermittent at best. For what it is worth, genetic evidence suggests the Bering Strait Variety of Bowhead are more closely related to the Hudson Bay stock than to the Davis Strait stock. It also indicates genetic separation of Hudson Bay and Bering Strait stock for at least 8,500 years; which is consistent with a forced separation by the closure of the North West Passage since before the Holocene Climactic Optimum. It should be noted that Atlantic and Pacific Bowheads have once again started intermingling. This evidence strongly suggests that the North West Passage and Canadian Archipelago was warmer than at present approx 10 thousand years ago at the last peak of northern summer insolation (red curve and figures): However, it also strongly suggests it has not been warm enough in that region to maintain open waters since then, even though the Earth itself was warmer due to the gradually melting ice sheets. Unless you have specific evidence of Bow Head populations intermingling in the North West Passage post 7,000 BC, you should stop using this evidence as though it suggested intervals of the passage being open throughout the Holocene. You frequently make that suggestion, but I see no evidence that supports it. (Note: cross posted from here as I believe this to be the most germane place for this discussion.)
  5. Tom: I wasn't talking about the NW Passage, but that's ok. Bow head whale proxy data: Calgary Research Bowhead fossils Please note that the above paper mentions a period of low ice and expansion of bowhead whale domain approx 1,000 YBP which correlates well with the pollin proxy data of 2,000 years of Climate Reconstruction.
  6. The first commercial ship to complete the Northwest Passage, in both senses, in the same year, was the US supertanker Manhattan in 1969.

    The second one, as far as I know, was the drilling ship Canmar Explorer II in 1976.

  7. I obviously meant "in both directions", East-to-West then West-to-East.  Apologies.

  8. MRoscio @6 & 7, the Manhattan was accompanied by an icebreaker, the USCGC Northwind, on its westward passage, and by another icebreaker, the USCGC Staten Island on its eastward passage.  At some unspecified stage, it also had additional assistance by the CCGS Louis S. St-Laurent.  This despite having been modified to itself be an icebreaker.   Likewise, the Canmar Explorer II was also accompanied by an icebreaker, the CCGS Louis S. St-Laurent.

    Given that multiple commercial ships and hobby craft transit the Northwest Passage every year now, without icebreaker assistance, I am not sure what your point is. 

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