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R. Gates

Another excellent analysis. Two things that stood out for me:

"To prevent my becoming a prisoner of premature spouting of speculations..."

Yep, I'm often guilty of that...

And you also said:

"One minor thing of interest is that according to the PIPS 2.0 sea ice thickness model the ice just north of Svalbard should be close to 5 meters thick, but I see mostly open water there. We'll get back to this one some other time."

Not meaning to steal your thunder on this one at all, but of course, it's well known that I think PIPS 2.0 is crap. There I said it...and I feel so much better.


Yep, I'm often guilty of that...

At the end of this month I'll have a full year of Arctic gazing under my belt, and that should hopefully be remedy some of the jumping to conclusions. But the annual melting of the ice pack in the Arctic is a fantastic spectacle to behold, even without the downward trend.

Nevertheless, there is a chance that sooner or later we will be seeing something spectacular, such as the huge calving off Petermann Glacier last year. And I'm mainly thinking of the disintegration of the ice pack into several big patches, like I've alluded to at the start of this blog post.

Not meaning to steal your thunder on this one at all, but of course, it's well known that I think PIPS 2.0 is crap. There I said it...and I feel so much better.

Well, if you absolutely have to steal my thunder, you might as well do it like that. :-)


I just noticed that PIOMAS has released another update. It's getting down to -9K or so....


I will be surprised to see ice in the Hudson Bay survive to July.


Thanks for the heads up Bill.

Granted that its a fairly nugatory exercise if hard data is being obtained from Dr Zhang's team, but I have calculated an updated dataset interpolated from the published graph, posted here: http://snipt.org/xwgn

By my reckoning, maximum anomaly for April is -9162, average is -8895. Average for the year to date (four months) is -8736, almost exactly 1000 km^3 below last years figures for the same period.

All four months have been lower that the linear trend, but also lower than the quadratic trend that started me off on this exercise. That is, ice loss is not only accelerating, but it is doing a good impression of accelerating at an ever faster rate.


What do you make of the past weeks increase in chlorophyll in the Barents Sea?

R. Gates

Re: Chlorophyll in the Barents Sea

This is not at all surprising considering the close association of melting ice and chlorophyll blooms. The release of fresh water encourages the chlorophyll growth.





That is true but it is the speed of the spread that I was commenting on and its potential association with the upwelling from the WSC


Thanks, Frank. I've updated the link to your interpolated dataset on the Arctic sea ice graph page.

Mauri, I wasn't aware of those chlorophyll blooms. Thanks for that link, those are some great looking graphs. Too bad I don't know how to interpret them (yet). Are these blooms early for the time of the year, or more widespread than usual?


I see some blooming here off the coast of Norway.


Now that Mauri mentioned it; I noticed the algae this evening, eyeballing MODIS, at the south tip of Svalbard. It assured my opinion on rapid melt in the northern Barentz Sea. An area where Neven gets excited on the possible dissection of a large part of the pack. The stuff UniBremen and CT graphs present as 70% covered sure looked like milk around some scattered floes today. Combine that with the SST anomalies supplied by NCEP and you get... a sense why Tamino is getting more urgent by the day (see his post on ‘hell and high water’).


Being very speculative but it could be that a warming artic region is likely to see much increased river discharge into the Ocean and will increase biological activity.


The chlorophyll is behind the 2010 levels and ahead of 2008 and 2009 levels in same region. The data maps do not go back past 2008 for May imagery anyway.

Rob Dekker

Thanks Frank, Neven, for the update on PIOMAS data. It looks like we are running 1000 km^3 below last year's trend. Last year, there was only 4000 km^3 left over in September (average ice thickness 80cm). In prior years, the volume difference sustains through the melt season, so we may be looking at a 3000 km^3 remaining ice pack in September.

On top of that, area is still some 250 km^2 less than last year, and if that sustains through the melt season, albedo effect may knock out another 500 - 1000 km^3, resulting is ice thickness of less than 50 cm in September.

One may wonder when the point will be reached when the whole thing would just break up into little pieces and melt away in the Actic summer sun....

Also, thanks Neven for posting Frank's spreadsheet again. Just one request : could you (Frank/Neven) possibly update and post the PIOMAS volume graph too ?
This graph is very revealing and visualised the PIOMAS volume estimates better than the spreadsheet IMO.


The extents is not changing to much but there is some amount of melting in the Altantic side of the sea ice at the minute. Going in way past the 85 degree line.

And as for Hudson bay. Blimey. At this rate it may only have a month of ice left in it this summer.

Its normally far too early in a season to say much abotu the year, but we are definently out the blocks and running now.


Something seems to be wrong with the Cryosphere Today numbers for 9 May 2011. Hudson Bay, Arctic Basin, and the Canadian Archipelago ice extents are showing significant drops.


Ah, they've been revised now.


I have to admit that for a minute I thought the graph for Hudson Bay was for real. :-D


Rob Dekker said, "One may wonder when the point will be reached when the whole thing would just break up into little pieces and melt away in the Actic summer sun...."

Both CT and MODIS show brutal, brutal leads opening north of Alaska.

I know I've been saying this for years, but I think this might be the year.

Rob Dekker

rlkittiwake "I know I've been saying this for years, but I think this might be the year."

I share your perception, but remember that there are still many unknowns. For one, PIOMAS volume data may be off, since calibration has been difficult since ICESAT went off the air last year, and Cryosat is still being calibrated itself. Besides that, weather in the summer has a big influence, and even then, even as little as 50cm sea ice in September may not break up completely. Still, when we look at the volume trends, it seems that with the loss of 1000 km^3 each year, the remaining 4000 km^3 should be gone by 2014 at the latest. So we may not see a total desintegration this year, but it sure looks like the odd are increasing rapidly...

Neven's latest post on ice thickness models shows more info, so maybe we should take the conversation there.


The area Svalbard to Franz Josef is showing a lot of open water and lots of lower concentrations of ice that are surrounded by ice. I wonder if when those melts break through to the open sea we will see a dramatic drop in extent? Also the ice tends to melt along the extent line and am wondering if this open water effectively increases the melt “front” by extended the line of where the ice and open water meet (if you follow).

It certainly piques my curiosity.


Indeed, dorlomin, I just noticed that MODIS has a very clear view today of the area around Svalbard and FJL. It's almost all open water between the two island groups. Amazing sight.


Definently clear melting going on above 85N now.

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