Friday, August 31, 2007

Ice free passage

The Northwest Passage has become almost ice free!

Once an impregnable forest of huge ice blocks, the Northwest Passage has — for the first time in recorded history — become almost completely ice-free and open to navigation. Researchers at the US National Snow and Ice Data Center recently announced that: "Analysts confirm that the passage is almost completely clear...
The source website, the Guardian put it more starkly:
The North-West Passage – the sea route running along the Arctic coastline of North America, normally perilously clogged with thick ice – is nearly ice-free for the first time since records began.
Since records began! What, since the turn of the century? The Second World War? 1842? 1726? 1938?

Analysts confirm that the passage is almost completely clear and that the region is more open than it has ever been since the advent of routine monitoring in 1972
1972, huh? How does that fit into Artic temperature anomaly patterns? Let's see now...

Click on that graph. The low point towards the right? The dip between two peaks? 1972, round about when the alarm was about global cooling - because temperatures seemed to have swung alarmingly low. The other high point? 1936, which fits the new data showing 1934 was the warmest year last century.

Out of interest, in what respect do these risings and fallings correlate with CO2 emission rates?

UPDATE: I meant to draw attention to the dishonest alarmism of the first quotation, from a site called treehugger. When did "recorded history" begin? Three thousand years ago? Fifteen hundred? Using this phrase makes it seem the Northwest Passage has never been this clear of ice, not since the dawn of time. Of course, the likelihood is it was at least this clear in the 1930s and for much of the Roman and Medieval eras. The only figleaf of accuracy that treehugger has is the strained truth that this particular set of recordings has a history that goes back just to 1972.

These people are just plain dishonest.

UPDATE: Strangely enough, this story didn't make the BBC website.

UPDATE: It gets worse. Much worse. Read this.

UPDATE: For people clicking through from the bird forum - the graph plainly shows the Arctic has warmed since the 1970s - there's no "denial" here, matey. Just an observation about the alarmist and dishonest way these things are reported, and the provision of some hard information to show that the Arctic is no warmer than it was in the 1930s. By the way, I love the commenter on your forum who says, in effect: I don't know why this is wrong, but I'll pop over to realclimate to get my prejudices confirmed. Oh, and while the graph is on the (excellent) junkscience blog, the data comes from James Hansen's NASA. So there.


Anonymous said...

The RCMP Vessel St Roche made an 86-day passage in 1944, which would have required substantial ice free sections. As well, she passed through the Northern route which is the only "international" passage.

J.M. Heinrichs

Anonymous said...

One should also note that the extent of Antarctic sea ice has reached a record maximum extent this SH winter.

Not reported on the BBC.

Peter Risdon said...

Yes, I did here. And see what I commented... Great minds work alike.

Anonymous said...

So you did!

We also need to remember that the Artic sea ice figures seem to have been subject to a large, unannounced adjustment affecting the period post 2000.

In other words they look like they've been fiddled.

Peter Risdon said...

Heh. This was a y2k bug in the analysis software. Hilarious.

Anonymous said...

It's not entirely true that it wasn't monitored before 1972. It was "monitored" when it was visited by explorers in the period 1818 to 1860 (approx). In this period of time almost this whole area was mapped out.

The first and most obvious point that any Arctic Historian will know is that this exploration-fest was prompted by precisely this. Wm Scoresby was the first to note in the early 1800s that the ice that filled Baffin Bay and the Northern Atlantic had melted, allowing ships to reach about 2 degrees further north than had been possible previously.

It is interesting that such changes in climate happened nearly 200 years ago, without the benefit of global warming.

The second point, equally clear, is that the amount of ice varies from year to year - significantly. An explorer would get their ship(s) into an area without too much difficulty and then be unable to get out for 2 or 3 years, or indeed sometimes at all (e.g. John Ross in the 1830s). Variations in ice are common - Franklin was not found for years because Peel Sound was open in 1846/7 but a solid ice sheet when the rescuers tried to find him.

Amundsen is not relevant to this discussion. The "passage" that has opened is the obvious one - leave Baffin Bay by Lancaster Sound and through Viscount Melville Sound. This was first navigated - by wooden ships - in 1818 by William Parry, who got further than Melville Island - this is "almost all" the "obvious" North West Passage. It is not normal, but is by no means unusual for this passage to be open water - in the era of exploration this point was reached by sail on a few occasions.

The last section and the most difficult, McClure Strait, was observed to be open water in 1854 (?) just before McClure went into Mercy Bay (where he became stuck, permanently). It is an open question whether if McClure had tried it, would he have been able to cross to Melville Island which would have allowed him to complete the passage by ship 50 years before Roald Amundsen did it (by hugging the North coast of Canada through Simpson and Dolphin & Union straits).

So the "opening of the NW Passage" is not quite the freak occurrence it is believed to be.