Sea ice extent update 10: leg broken?

I'll be regularly writing updates on the current sea ice extent (SIE) as reported by IJIS (a joint effort of the International Arctic Research Center and the Japan Aerospace Exploration Agency) and compare it to the sea ice extents in the period 2006-2009. The JAXA graph is favoured by almost everyone, probably because it looks so nice compared to other graphs (like the one by Arctic ROOS, the University of Bremen and the Danish Meteorological Institute). All the years have a nice colour of their own which makes it easy to eyeball the differences between trends. Most of the betting on minimum SIE is based on the IJIS data. NSIDC has a nice explanation of what sea ice extent is in their FAQ.

July 1st 2010

Another month in the melt season has gone by. 2010 didn't clinch that century break record, but the average daily melt was more than 10,000 square km or 17% above the previous record of 2007. The last two days ended with relatively low reported melt numbers though, when the exact opposite was expected.

Expected by everyone? By a lot of people perhaps (including me), but not by Steven Goddard, the cryospheric expert over at WUWT. Just a few days ago he predicted that "in three days, the slope of the Arctic extent graph will begin to drop off". He actually was off by 1 day, as yesterday's reported melt of an average 75,469 square km was followed today by a staggeringly low 45,000 square km. The first number was the second lowest melt of 5 for that date and today's number is the lowest of 5, going under 2006's reported melt of 52,500 square km. It has been exactly 32 days since 2010 had the lowest reported melt in the period 2006-2010.

It's not a U-turn yet, more like a J-turn (with the J flipped), but if this isn't a temporary thing 2007 will gain the lead in no time as it has 4 more century breaks in a row coming up and a few more down the road as well. We'll have to wait and see if 2010 can step up to the challenge.

The current difference between 2010 and the other years is as follows:

• 2006: -451K

• 2007: -570K

• 2008: -921K

• 2009: -949K

Here's the IJIS graph:

And a close-up of the flipped J (2007 is dark green):

One factor in the slow-down could be the persistent negative Arctic Oscillation as shown by NOAA's daily AO index:

When looking at AARI's forecast of mean daily drift of sea ice, we see that they expect the Beaufort Gyre to reverse temporarily keeping the ice from flowing out of Fram Strait:

 

After a precipitous drop the Cryosphere Today sea ice area anomaly has finally gone up approximately 0.1 million square km:

TIPS - Other interesting blog posts and news articles concerning Arctic ice:

An interesting article in the Winnipeg Free Press discusses the lack of interest on the part of shipping firms in the Northwest Passage as a potential money-saving alternative to southern routes.

The Chinese and the Russians are off to the Arctic Ocean.

A few days ago I watched the documentary The Search for the North West Passage (watch it on Youtube), depicting John Franklin's failed expedition in the 19th century to find the fabled short-cut through the Canadian Archipelago. So it was with interest that I read on CBC News that "Canadian officials will return to the Northwest Passage this summer in search of Sir John Franklin's long-lost ships, after efforts were postponed last year". Read on.

Comments

[Kevin McKinney]

Well, this decline in melt rate was not foreseen by me, certainly! (Although--is it well-described as a decline in melt rate? Extent is not driven purely by melt, as we know.)

But I'm skeptical that this marks a turning point in the "race." There's always a lot of variability and a bunch of factors play into it. I think there's still lots of vulnerable ice and certainly conditions in the Canadian Arctic (as I keep repeating--sorry!) continue very toasty indeed. We'll certainly see in due course!

Question--your commentary, Neven, says AARI "expect the Beaufort Gyre to stall temporarily," but all those motion vectors on their map don't look like a "stall" to this naive eye. Can you elaborate on this a bit? (I certainly see what looks like transport into the Fram Strait--ie., ice moving back into the Arctic basin!)

On another note, although the CT image for 6/30 still looks quite alarming, this is I think also the first time lately that the area anomaly has decreased--so CT is also reflecting what we see in the JAXA number, presumably.

[Kevin McKinney]

Oh, and thanks for the interesting links, too!

[Gili1]

Hi,

The AARI drift forecast for 4-6 days is very strange: it reverses the direction of both the Beaufort Gyre and the TransPolar drift-- I think you should ignore it. Thanks for the nice constant blogging work.

-Gili

[Andrew Borst]

Looking through older ice flow charts you can see the direction of the ice in the Beaufort Sea does change direction periodically. It appears that the changing direction of the current has stopped the ice flow over the last day or so. It will be interesting to see if the flow rate increases going the opposite direction and how much ice is pushed out of the two straits.

http://iabp.apl.washington.edu/Summary/8309.gif

[Neven]

Kevin, 'stall' wasn't the right word. I've changed it into 'reverse', which is more accurate.

Thanks, Gili. I'll be keeping up the updates and hope to intersperse them with a thing or two the coming days.

The AARI drift forecast for 4-6 days is very strange

I still don't understand how this forecast works, but I like the arrows. Is it updated every 6 days? And are the forecasts retrospectively updated with real time data?

[toby]

Could not watch the Sir John Franklin documentary. Not available in Ireland.

There is a lovely old sea shanty for anyone who like those types of songs called "Lord Franklin". Enjoy. My compliments on the great website.

http://www.youtube.com/watch?v=Kj4RHYJdcE4&feature=related

[Lord Soth]

We are 570K below 2007. It is going to take a sustained change in weather for 2007 to catch up. We have less ice volume than 2007, so even if 2007 does catch up, I see 2010 maintaining 2008 rates and surpasing 2007 in August.

[logicman]

Neven: can you provide a link to where Steve Goddard made that statement? I'd like to see exactly what he was predicting and on what basis.

I expect that the gyre reversal will not slow down the export of ice via Nares Strait. It may well increase the dispersal and melt in the Pacific sector of the Arctic. Most of the open waters along the Alaskan and Canadian shores are quite warm now, so any extra flow of broken ice into those waters will accelerate melt.

My latest prediction is that the rate of ice loss as shown in NSIDC and JAXA graphs will accelerate about July 8th. Feel free to laugh and wag fingers if I am wrong. :-)

I'll be updating my blog soon. Many thanks to the people who have visited my blog via Neven's site, and thank you Neven for the many links you have posted.

[Nick Barnes]

Check out today's Terra image for the crack showing the next big loss at the eastern end of the ice bridge in the NWP: a big triangle of ice, with its base across the whole of Viscount Melville Sound (about 140km N/S, and maybe 60km E/W). The Aqua image shows that two more triangles are ready to come after that, after which there'll be about 150-200km of ice bridge remaining in the deepwater channel. The other side of Stefansson Island, there's another 30km chunk breaking off in the McClintock Channel.

[Account Deleted]

The other area that looks like it may start to clear quickly is the Laptev Sea - the Uni Cologne Mets site http://www.meteo.uni-koeln.de/meteo.php?show=En_We_We has toasty condition for that region at the moment and the forecast on Weather Underground, for the few station that seem to exist in that region suggest that these condition will last for a few days.
PIPS also suggest that the ice is relatively thin in that region.

[Chartsgraphs.wordpress.com]

Neven

I've been experimenting with how to show the changes in rates of daily SIE decline for 2010 and 2007. I've been using a table of comparative rates for previous periods. My latest attempt plots the actual daily 2010 - 2007 SIE differences. Here's a link my latest attempt:

http://processtrends.com/images/RClimate_JAXA_Arctic_SIE_2010_2007_latest_diff..png

Which display method do you prefer, the data table of rates or the differences plot? If I put both the data table and the difference plot on the same display with the SIE trends, the text is unreadable. I'd appreciate feedback on which method is easier for readers to pick up changes in the 2010 versus 2007 situation..

I plan to start plotting the 2010 - 2007 Cryosphere Today Sea Ice Area data and would like to use the same plot layout for both SIE and SIA.

Kelly O'Day

[Kevin McKinney]

A moderate decline for today--63.5k or so, according to the prelim.

[Neven]

Nick Barnes, thanks for that comment. I'll be updating the NWP animation in a minute.

Kelly, I prefer the lower graph which visualises the difference in extent between both years, the upper graph is the same as the IJIS graph but without other years.

If I could be so bold, I'd like to see a graph that shows what they call a moving average, I believe,of the last 10 days or so, like Gas Glo made here: http://www.flickr.com/photos/37346653@N05/4738373888/

[Gas Glo]

Update on my graph - 14 day average:

http://farm5.static.flickr.com/4075/4754564774_c9243458a9_b.jpg

A few things I have been wrestling with about this graph:

The heat transfer in is maximum at soltice (subject to weather variation). The peak melt rate is always later which is not too suprising - the later in the melt season the thinner the ice.

After the peak melting rate, the downward trend in rate is suprisingly linear. (OK 2008 does not look linear but then 2009 has a big jog in the other direction.) The heat transfer in is not linear, so what pattern of increasing areas of just above 15% ice cover occurs to make the trends in ice melt rate look linear?

If the volume is particularly low this year, presumably this pattern of increasing areas with low ice cover may be more important this year so leading to a more curved in 2008 direction shape.

The date of peak melting rate seems more variable than the date when net melting ends:
2010
2009 26/07/2009
2008 26/07/2008
2007 13/07/2007
2006 06/07/2006
2005 31/07/2005
2004 09/08/2004
2003 25/07/2003

peak rate 35 day range

1st positive 15/09/2004
last negative 27/09/2003

zero rate 13 day range

If 13 days reflects weather variability, are the other 22 days of peak rate variability predictable from factors other than weather?

Thoughts anyone?

[dorlomin]

Tamino joins in with the ice nerds
http://tamino.wordpress.com/2010/07/01/on-thin-ice/

[Lord Soth]

Goddard made an interesting observation about Hudson Bay, with the rate of decline slowing with most of the ice in Hudson Bay gone. The fact that his prediction came true, is however pure coincidence.

Sure Hudson Bay has melted out, but there are new candidates for rapid ice loss, for example the Laptev Sea, Baffin Bay and others.

However, at some point, once most of the first year ice south of 80 is melted, we will run out of "easy ice to melt".

At some point all that is left, will be mostly second and multiyear ice, which will be more resistant to the melting process.

At that point we will be dependent on wind patterns pushing this ice into the slightly warmer southern arctic waters of the beaufort sea, and ice export from the various straits.

I'm 100% confident that 2010 will be in the top three for ice loss regardless of weather, and there is a good probability that we could reach a record ice loss in the high 3's million sq. km.

[Kevin McKinney]

gas glo, since you ask--I wouldn't be too sure about the concept that solstice=max heat in.

Radiation, clearly (and subject to weather variation, to be sure, as you also note.) But it was noted earlier--don't remember who made this point--that there is a considerable thermal lag. I imagine it's actually different for different components of the system (ocean, lower trop, whatever.) And they are thermally coupled with differing efficiency (if that's the word.)

In a word, warmer currents and warmer winds keep bringing heat in after the height of radiative cooling. I've no clue about the numbers here; I'm a musician, not a scientist. But this seems likely to give ample scope for the kinds of variability that you note.

My two cents.

[Artful Dodger]

It's raining on the North Pole StarDot NetCam (Thu Jul 01 19:45 UTC). You can also see a rainbow on the left edge of the other camera, both available here:

http://sites.google.com/site/arcticseaicegraphs/

[Neven]

Sure Hudson Bay has melted out, but there are new candidates for rapid ice loss, for example the Laptev Sea, Baffin Bay and others.

Yes, I noticed this too. The CT sea ice area of the Arctic Basin, which looks to me the most important and biggest of all regions, is still dropping precipitously.

[Kevin McKinney]

Oops--I wrote "radiative cooling" for some reason in my previous comment when I meant "radiative heating"--probably obvious. Sorry, anyway!

If you look at CT basin by basin, several are now kind of "tapped out"--Bering Sea, of course, Gulf of St. Lawrence (which had very little ice all winter anyway, this year.)

A couple of semi-random thoughts I'd like to invite reactions to:

1) Noting the NCDC SST maps, you can see elevated temps in several of the newly ice-free areas, such as Baffin Bay. I'm wondering how much previous-year data they have for some of these areas? Hudson Bay, for example--much of it is normally still ice-bound at this time, so what is the SST baseline in such a case?

2) We'd been talking about the Beaufort Gyre reversing; it occurs to me that that should have a significant fracturing effect on the ice, yes? There'd be some pretty enormous mechanical stresses, plainly. Of course, that's a bit of a double-edged sword; on the one hand, new fractures result, but on the other you get pressure ridges and floes overriding each other, which gives local thickening.

[dorlomin]

Noting the NCDC SST maps, you can see elevated temps in several of the newly ice-free areas, such as Baffin Bay.
= = = = = = = = = = = = = =
Energy going into heating water rather than melting ice?

[logicman]

"Energy going into heating water rather than melting ice?" Exactly!

Last year the summer heat went directly into warming up Baffin Bay, Nares Strait and Lancaster Sound. When the ice arch collapsed, most of the ice melted before ever reaching Baffin Bay, until about September.

This year, much of the summer heat has gone into melting the ice which has been flowing from the Lincoln Sea since last year. I expect the Baffin Bay area to start playing catch-up about now.

Compare the Rapidfire mosaics for this year and last, by editing the url to show 2009 instead of 2010. Look especially at Baffin Bay.

http://rapidfire.sci.gsfc.nasa.gov/subsets/?mosaic=Arctic.2010182.terra.4km
http://rapidfire.sci.gsfc.nasa.gov/subsets/?mosaic=Arctic.2009182.terra.4km

[www.google.com/accounts/o8/id?id=AItOawn6XOWW-fGm0xLA4i_wDdh_m_IknX4cxQw]

NOAA SST maps now updated (down for last few days) and a big increase in temp(+5C in 3 days) in both beaufort bay, chuckchi and boffin bay.

With spots of 8 to 10C now shown over last two days - this will speed up the melt of all that fractured thin ice shown by the rapidfire maps in chuckchi and beaufort.

Its amazing to see how fast Hudson bay is heating up now that less then 10% ice remains (150k left out of 1.2million ave max)

NOAA SST links -
http://www1.ncdc.noaa.gov/pub/data/oisst/amsr-anom-bb.gif
http://www1.ncdc.noaa.gov/pub/data/oisst/amsr-sst-bb.gif

Poseidon

[Neven]

Lord Soth, I'm quoting you for the second time:

Sure Hudson Bay has melted out, but there are new candidates for rapid ice loss, for example the Laptev Sea, Baffin Bay and others.

When looking at the CT sea ice area maps it seems to me like it's the Greenland Sea, the Barents Sea and particularly the East Siberian Sea that are being the pary poopers here. This is obviously compensating the drop in the Arctic Basin sea ice area.

And like logicman says the ice is also spread out across Baffin Bay because of the steady transport of ice floes through Nares Strait and Parry Channel.

These could be the reasons for the slowing melt rate.

[Account Deleted]

There seems to be a bit of disagreement between the Russian and the American about Ice Displacement. The AARI site suggest that little ice is being exported into the Greenland sea at the moment, whereas the PIPS site suggest there should still be a fair amount.