Sea ice extent update 27: nope, not a fat lady (yet)

I'm 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 IJIS 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 good explanation of what sea ice extent is in their FAQ.

August 29th 2010

The 2010 melt season keeps stumbling forward. Days of 20-30K decreases (August 23rd, 25th and 26th) are alternating with decent daily decreases of 50K (24th and 28th) and a very decent daily decrease of 78,437 square km (on the 27th).

This means that after having crossed the minimum extent thresholds of all years in the IJIS database prior to 2007, 2010 could be diving under the 2009 minimum extent in two to three days from now, which - with several other (strong) indicators - is making any talk of a continued recovery impossible.

Next up is the 5 million barrier. I don't think 2010 will be taking over 2008, as the latter had a strong run in the past days that has increased its lead over 2010 considerably. But it all depends on the weather and the final date of minimum extent.

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

• 2006: -624K (37,697)
• 2007: +618K (57,041)
• 2008: +164K (70,333)
• 2009: -212K (48,654)

The average daily melt for the month of August is between brackets. 2010's average daily melt for August is currently 56,406 square km per day.

If 2010 loses as much sea ice extent as...

• 2006 did after this date it will bottom out at 5.15 million square km.
• 2007 did after this date it will bottom out at 4.87 million square km.
• 2008 did after this date it will bottom out at 4.87 million square km.
• 2009 did after this date it will bottom out at 5.04 million square km.

Here's the IJIS sea ice extent graph:

 

Meanwhile the Cryosphere Today sea ice area anomaly is on the increase. A few decent decreases, combined with the 1979-2008 mean starting to level off significantly, have moved the anomaly number towards 1.5 million square km again. Most of the decreases are showing in the Arctic Basin (that has already dived below last year's minimum for this region). Sea ice area in the East Siberian Sea has been dropping for a few days as well, as has the Canadian Archipelago sea ice area, despite all that multi-year ice from the Arctic Basin that keeps spilling into its straits and channels.

The relatively large drops in sea ice area are also having its effect on our compactness graph that shows the ratio between CT sea ice area and IJIS sea extent. It currently stands at 65.34%:

 

Despite the recent domination of low-pressure areas in the Arctic, a high-pressure area manages to stay put over the Beaufort Sea. In fact, ECMWF is forecasting this high to strengthen in the coming 10 days, combined with some very big cyclones on the other side of the Arctic. If this forecast comes about we will be seeing one hell of a Dipole Anomaly:

1040 mb on one side of the Arctic, and 990 mb on the other... That can't be good for the fractured, ulta-mobile ice.

The first instalment of my End Zone-series on air temperatures will be followed later today by an animated comparison of PIPS ice displacement maps from the final weeks of melt in previous years. I have a feeling that the date of minimum extent is preceded by PIPS ice displacement forecasts with small arrows in them.

I have a hunch the the direction of the arrows isn't as important as their size. Whichever way they're pointing, as long as their big, extent keeps decreasing (fast). We'll see what happened in previous years later today, but for now PIPS is still forecasting big arrows:

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

Chris Mooney has written a fantastic article for NewScientist called Arctic Ice: Less Than Meets the Eye.

Meteorologist Jeff Masters has also written a very good summary of the current situation in the Arctic on the Wunder Blog. Joe Romm quotes this article extensively on ClimateProgress.

Patrick Lockerby is feeling better again and delivers a great piece on Petermann and Jakobshavn Glaciers, and glaciers in general.

Wayne Davidson writes about the apparent contradictions in the Arctic, part of the same process:

The heat of 2010 was so strong it reversed the usual High pressure usually centered North of Alaska, the very reason for the Beaufort Arctic Ocean gyre was nullified by a near constant low pressure in its stead. Even in 2007, equally a warm year, this High pressure stood out as the main reason causing Arctic Ocean all time melt. In principle, a natural High anticyclone exists at the Pole, just like the Earths magnetic poles, it is not situated at the North geographic Pole but North Of Alaska, making perfect sense, usually explained by Hadley cell circulation. However 2010 summer had the reverse Hadley cells at the Pole, or likely a split Ferrel like configuration. Leaving the Sub-Arctic immersed in clear air , causing record heat signatures throughout the Northern Hemisphere, characterized by near static high pressures baking places like Western Russia and the island nation of Japan. The clear air expected due to La-Nina manifested itself there. The outstanding feature of this is the seemingly puzzling flow of warmer air towards colder air Northwards in the Arctic, which is usually not the case, since colder Arctic air is denser, thus is naturally under higher pressure, but the heat generated by static sub-arctic highs maintained descending air, with higher pressure, reversing the usual scenario, causing heat to flow Northwards, naturally causing unstable convection (fueled by high latitude colder upper air) rising at the Pole causing clouds, forced clouds, not the typical Arctic seeded clouds from descending air. In short, quite a remarkable planetary wide role reversal.

Comments

[JackTaylor]

Steve, where I wrote Nares Strait @ 04:28 add - change it to Fram Strait. Oops.

[Phil263]

With 5,249,688 SIE reported by JAXA today, 2010 has just nudged under 2009 ( by 156 sqkm !!!). Whether this report survives tomorrow's revision, a 54k decrease is significant so late in the melting season.

[FrankD]

Pending any revisions, we have a significant number on IJIS today: 5,249,688.

Having finally passed 2005 yesterday, today's figure is just below the minimum of 2009 (5,249,844 on 13th Sept), leaving only 2008 and 2007 out in front.

2008 minimum is still 540,000 sq km away, so I doubt we'll be reaching that (even 2007 only lost 330,000 sq kms between the 3rd and its minimum on the 24th), but the gap has closed a bit.

[Kevin McKinney]

. . . and the prelim SIE is---5,249,688 km2!

That's under the 2009 minimum (5,249,844) by a couple of hundred.

Now the wait for the revision. . . .

[Jon Torrance]

FrankD,

A note - 2007 wasn't the biggest loser from September 3rd to the end of the melt season in the JAXA record. That distinction belongs to 2005, which lost another 374,219 km2. Not a huge difference but considering how much more fragile the ice surviving now is compared to most of the ice that hadn't melted by this point in 2007 (and the fact that there's more extent therefore the edge of the icepack has to be further south on average than in 2007 and presumably exposed to warmer waters), 2010 could yet surprise us. Not to say I'd bet on it overhauling 2008 but we're entering uncharted waters here, with the best available model suggesting we're all but certain to have lower arctic sea ice volume this month than humans have ever witnessed before. I think people are a little bit too dismissive of the odds of quite a bit more extent loss to go, if the weather over the next few weeks is favourable to extent loss. History may be the best guide those of us who aren't up to modeling the physical processes have, but just because something is unprecedented doesn't mean it's can't happen.

[Lord Soth]

If you look at the NSIDC ice extent, you will notice that there was no flat line, just a nice steady decline.

http://nsidc.org/data/seaice_index/images/daily_images/N_stddev_timeseries.png

Now NSIDC does average for 5 days, but since the flatline on IJIS covered a 4-5 day period, we should have seen something.

I believe NSIDC uses a larger area for pixel size (resolution) than IJIS, and it looks like the flat line was just noise within the resolution that IJIS was using.

With 250K to go to break the 5M barrier, it it still possible.

What ever the outcome, it appears that 5 million sq km, plus or minus some standard deviation, has become the new normal for Minimun Sea ice Extent, and any talk of recovery should be put to rest.

It will be interesting to see if we will get a catastrophic drop to zero volume, or if it will be a series of declines on good weather years, followed by a period of leveling within a small range with bad weather years. The next few years should be interesting.

With Hurricane Earl makine a unwelcome visit to Halifax, this may be my last post for a few days.

[Kevin McKinney]

Good luck with Earl, LS. . .

[Glacierchange.wordpress.com]

I cannot wait to see Update 28. I have posted a discussion on Humboldt Glacier , what I have I not thought of that needs to be covered? What images are musts to use from MODIS? I look forward to further valuable input.

[r w Langford]

Jaxa SIE Sept 3, 5.25. The graph mimics 2007 with this large drop in the last two days.

[Neven]

r w Langford, congratulations, that was comment number 2000!

Continue at the newest SIE update 28, please.