SIE 2011 update 19: the fat lady is humming

During the melting season 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 2005-2010. NSIDC has a good explanation of what sea ice extent is in their FAQ. I also look at other things like sea ice area, concentration, volume, temperature and weather forecasts, anything that can be of particular interest. Check out the Arctic sea ice graphs webpage for daily updated graphs, maps and live webcam images.

September 3rd 2011

We are slowly approaching the end of the melting season. 2011 has secured a second spot on most area and extent graphs. The only question now is whether there's enough momentum left to break the 2007 record(s).

We have seen some signs this melting season that extent and area numbers aren't so dependent on weather conditions any more. In the past week for instance, we saw how a small and short-lived high-pressure area over the Beaufort Sea almost led to a century break and two more days of above average extent decrease.

In absence of a strong Beaufort Gyre and Transpolar Drift Stream we can only conclude this has to do with the weak or slush puppie ice at the Pacific side of the ice pack. It did quite a lot of melting in situ and who knows how well it would have compacted had weather patterns looked anything like 2007. Because, just like last year, they didn't. Around mid-July the weather turned bad for extent decrease, recovered somewhat after 3 weeks, but with hiccups. This kind of weather in the pre-2007 era would have inevitably led to a minimum extent above 5.5 million square km.

Still, there is one thing that can prevent weak, thin ice from completely melting out, and that's freezing temperatures and diverging winds. In other words, the end of the melting season. Last week I ended my introduction to SIE update 18 with the following remark:

Barring some really strong weather patterns that keep the ice in place and freeze the water over at the edges, we are in for a final phase of the melting season where everything is possible.

So what can we expect? More on that further below, but I think the fat lady could be humming a few bars. 

Sea ice extent (SIE)

Here's the current IJIS SIE graph:

2011 has halved 2007's lead yet again, but didn't manage to fully profit from 2007's slow extent decrease of the last couple of days. I think it's going to be very difficult to break the IJIS record minimum extent now, because 2007 had three weeks of extreme compaction in the final weeks of the melting season, leading to some very strong extent decrease days (for the time of year), and of course a very late date for the minimum extent. However, 2011 is about to edge past 2008's minimum extent in a day or so.

The current difference between 2011 and the other years is as follows:

• 2005: -950K (+3,370)
• 2006: -1257K (+234)
• 2007: +104K (-469)
• 2008: -237K (+172)
• 2009: -678K (+6,417)
• 2010: -583K (+7,865)

Between brackets is the average daily extent decrease for the month of September. 2011's average daily extent decrease for September is currently -11,485 square kilometers. But this doesn't say anything of course, as we only have 2 days so far, and we get a lot of extent increase after the minimum extent. Do note however that 2007 is the only year with a negative average.

If 2011 loses as much sea ice extent as...

• 2005 did after this date it will bottom out at 4.37 million square km
• 2006 did after this date it will bottom out at 4.52 million square km
• 2007 did after this date it will bottom out at 4.36 million square km
• 2008 did after this date it will bottom out at 4.47 million square km
• 2009 did after this date it will bottom out at 4.57 million square km
• 2010 did after this date it will bottom out at 4.23 million square km

The 2007 IJIS minimum extent was 4.25 million square km. 2008 was 4.71 million square km. We are currently at 4.72 million square km.

Sea ice area (SIA)

The Cryosphere Today sea ice area numbers went up quite a bit, but have come down again and we are only 10K away from going below this year's preliminary minimum SIA of 2.983 million square km. SIA is lower than 2008 and 2007 were around this date, but another 75K is needed to break the 2007 record minimum area.

The Cryosphere Today SIA anomaly graph is of course still showing the largest anomaly ever recorded for this date:

As we can see on the Regional Graphs page, the Arctic Basin and Canadian Archipelago are relatively flatlining at the moment. Everything seems to depend now on the slush puppie ice left in the East Siberian Sea that still has some more room to go down, as has the Greenland Sea graph.

Cryosphere Today area per IJIS extent (CAPIE)

On our CAPIE graph we can see how 2007 started shooting up towards the end of August, due to freezing over of melt ponds and of course compacting winds. We see this year's trend line going up as well, but not as strongly. To really break records, CAPIE will have to go up by a couple of percentage points. And not because freezing melt ponds cause SIA to shoot up, but because compaction makes SIE go down faster than SIA.

Sea Level Pressure (SLP)

As usual, we first have a look at the animation of SLP images from the DMI Centre for Ocean and Ice to see what happened in the past week:

The high that caused IJIS sea ice extent to dip quite fiercely, can barely be made out, if just by the isobars above the Beaufort Sea with a tinge of yellow in the middle. The only other noteworthy thing is a cyclone over Svalbard towards the end of the animation. This didn't seem to have much of an effect, except perhaps for some transport towards Fram Strait (which reminds me, I have to update the animation).

Now we come to the reason I'm thinking I can hear the fat lady humming a few bars. The weather hasn't really been great for extent and area decrease in the past couple of weeks (even though extent and area dropped without cessation). I remember how last year around this time some high-pressure areas managed to elbow their way into the American side of the Arctic - ie Greenland, the Canadian Archipelago and the Beaufort Sea - causing trend lines to drop quite a bit more, all the way to a third position on most graphs. But this year those highs simply aren't there (or just for a very short time) and according to the ECMWF weather forecast maps they're not going to come in the next 7 days either:

Update conclusion

As things now stand, I think we're going to see an early end to the melting season. SIE will drop some more, and so might SIA. But with the weather forecast maps showing a lot of SLP areas flipping around (which is never good for extent decrease as it needs stable weather patterns to go down steadily), and on top of that the Arctic being dominated by low-pressure areas, I don't think the combination of thin ice and warm waters is going to be able to put up a fight against diverging winds and freezing temperatures.

Of course, I could be wrong. There still is a huge area - in the East Siberian Sea mainly - with low concentration ice that could melt out in a flash under the right circumstances (a gyring Beaufort Gyre and a streaming Transpolar Drift Stream). And maybe it will even melt out significantly in absence of those right circumstances.

In this sense, the ice pack is going to be confronted with the ultimate challenge. Have we definitely reached the stage where the ice melts out, regardless of weather conditions, even at the end of the melting season? Or will that be for another year?

We are going to find out in the next two weeks.

 

---

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

Patrick Lockerby has just released his latest blog post on Arctic Ice: September 2011

Tamino explains convincingly that the Death Spiral Continues

Comments

[Ian Allen]

I think we need as many vigorous little cyclones as possible now to churn the slush in those still-warm waters.
They are more likely to visit now we have such warm water.

[D]

IMO.If the storm, below iceland, on the DMI graphic stays close to greenlands coast we could see big changes this week. Currently looks just as likely to pass east of Svalbard.
Is it safe to assume that the sea surface temperature [by greenlands coast] is influenced to a large extent by fresh water and that warmer currents persist below?

[Steve Bloom]

Sea ice data fans will want to read this and the following comment at RC.

[Espen]

Yes I have long felt it was more or less pure guesswork, but I'm sure that ice volume has decreased significantly!

Regards Espen

[Paul Klemencic]

Bremen preliminary map comments:
Yesterday an interesting movement of the ice pack showed up. The arm of ice that extends up into the E. Siberian sea began to split down the middle. With the wind driving toward the NP, then splitting with some wind pushing ice toward the Chukchi, and the other side of the Arm being pushed toward the Laptev, large extents of open water began opening in the middle of the Arm. Essentially we are seeing the formation of two somewhat shorter skinnier arms, rather than one Arm.
This continued in the preliminary map today.

This is likely the most devastating development possible for the E. Siberian sea ice this time of year. If the arm moved toward the Laptev, only that edge of the pack would be pushed over warmer water. Likewise, if the wind blew the ice the other way toward the Chukchi, only that side slides over warmer water. With the arm splitting, now two edges are being pushed over warmer water, AND there is open seas and additional ice pack edge created in between the arms.

Since the E. Siberian sea contains about 400k sq km of vulnerable ice broken into pancake ice, this could have a big impact on extent over the next week.

The other regions with a lot of vulnerable ice are the Beaufort, Chukchi, and Laptev. Starting with the Beaufort, the ice spread toward Alaska yesterday, but today seemed to shift direction, and is compacting back into the pack. This could lead to some sizable extent loss today, but will make the ice more difficult to melt soon, since temperatures usually drop in September to the point where the floes start freezing back together.

The Chuckchi is not visible on the prelim map, and yesterday had spread out some. Not much change in the Laptev today, but the eastside edge is being pushed toward Siberia all the way down to the Fram. The ice in the Greenland Sea is splitting apart because of diverging winds similar to the E. Siberian, and will likely cause a significant increase in the ice usually able to "hide and survive" next to Greenland.

The action that counts is really in the E. Siberian yesterday and today.

[Chris Biscan]

The DragonballZ video is priceless and awesome.

A few videos representing the SSTs vs Ice is.

Super Vegeta vs incomplete Cell

Gohan vs Perfect Cell

Vegeta vs Android 19.

Goku vs Freiza

Trunks vs androids back in his time after the cell games.

[Phil263]

Neven

Excellent update as usual. I would concur with your assessment that there is a high probability that we will see an early end to the melting season this year mainly because of weather conditions. I'd say in the coming few days,probably before Sept 10th. Notwithstanding the state of the ice and its effect on the trend, short term conditions are determined by the weather. Just like you can leave in area where the climate is getting dryer over the years, but still get a soaking wet year (eg Australia in 2010/11)!

Steve Bloom @ Sept 3 22.13
Thanks for providing us with the link to the comment on RC about models. I particularly agree with the opinion that even though we can rely on models to give us an indication of a qualitative trend, we cannot trust them to give us an exact figure of SI extent, area or volume.

[Chris Biscan]

The SST anomalies are twice that of 2007 in many cases.

It's very unlikely the melt season wont end until 20th or later with so much warm water out there.

[Phil263]

Fixing the typo above: Oops!

Just like you can live in area where the climate is getting dryer over the years, but still get a soaking wet year (eg Australia in 2010/11)!

[Chris Biscan]

I live in the epitome of a Four Seasons Climate.

Winter has 25 inches of snow with temps getting -20C(-5F) during winter cold out breaks. And 40C(100-105F) during summer heat.

Wind chills in the (-30C or colder range and heat index in the 45C or warmer range)

but overall we are dramatically warmer since the 1950s-mid 1980s.

Most Octobers-March is way above normal.

Some months have gone up 5-6C mean temp for an entire month.

My grandfather kept track of days with snow on ground. at least 1/4 inch over 50%.

We had winters with 70-80 days of that in the 1950s-80s and now some with less then 10 days.

It's crazy.

[Chris Biscan]

UB final is out.

If today doesn't reflect it. Based on winds.

we will see a 3 day period starting today with 150Km2 loss or so.

I am predicting 49,000km2 tonight loss on jaxa and 75,000km2 tomorrow.

[Lucia (The Blackboard)]

Chris--
I just went to Jaxa:
09,02,2011,4720781
09,03,2011,4682188
I think this posted within the past 10 minutes.

[Chris Biscan]

-38,600km2 on Jaxa down to 4,682,188km2 new 2nd place on the all time low list.

Gonna see at least another 100,000km2 come off Jaxa over the next two days.

[Kevin McKinney]

Yes, 4,682,188 km2 clinches a second-lowest IJIS-JAXA SIE minimum for 2011.

Can it still threaten 2007? A long shot, but I'm not so convinced of an early minimum yet.

[Michael Fliss]

What are the possibilities for weather with this low over the Beaufort Sea?

http://www.uni-koeln.de/math-nat-fak/geomet/meteo/winfos/arcisoTTPPWW.gif

[Bob Wallace]

Working off the PIOMAS volume graph, 2011 had about 75% as much ice as 2007 at the end of July. So considerably less ice to melt spread out over a slightly larger area.

Let the residual heat do its job....

[Neven]

Michael Fliss, I think that low is a fluke (not the first time that happened on the Uni Koeln weather map).

[Phil263]

We're getting very close to Tamino's model prediction of 4.66 million. Almost spot on like he was last year! (unless extent goes much further down)

[Rob Dekker]

Neven I think we're going to see an early end to the melting season.

This contradicts my projection (done ealier) that we will get a late minimum, due to prolonged bottom-melt. Your arguments I don't think the combination of thin ice and warm waters is going to be able to put up a fight against diverging winds and freezing temperatures. are very convincing, but I still feel that 2011 melting season may just have one more trick up it's sleeve. Ice is still fragile. So fragile that one storm (mixing warm ocean water with surface ice/water) may do the trick.

Still, the way it looks now, you may be right and minimum may be early.

But it's not over until it's over...

[BilltheillFrog]

If one crunches some numbers from CT, it appears that another little milestone has been passed that further erodes the "Arctic Sea Ice is recovering" and the "Arctic loss balanced by Antarctic gain" nonsense.

After importing the CT Global Sea Ice Area data, a filter was applied to pull out days that had an anomaly greater than 2 million sq km. Thus far, the entire dataset contains just 80 such occurrences in its 32+ year span.

This first happened in 2006, and the subsequent frequency of such events was as follows...

2006 4
2007 24
2008 21
2010 6
2011 25 (thus far)

Of the 55 that happened prior to this year, no fewer than 39 of these (71%) happened later in the year than mid September. That would certainly suggest there is a fair to middling chance that we might just see a few more >2 million sq km Global SIA anomalies this year.

Looking at the year-to-date Global SIA average, this year is currently running about 16.92 million sq km, with 2007 at 17.01

Shifting focus to just the Arctic, I have yet to see a properly explained justification for the unwavering belief displayed on certain websites in this purported recovery of the Arctic ice. Partly, this seems to be fuelled by the frankly ludicrous "logic" that says...

"The Arctic SIE minima reached a nadir in 2007: the fact that it is recovering is self-evident as the 2007 figure has not been breached for the last 4* years." (* NB One can insert any number of choice.)

Unfortunately, if one chooses to look at something beyond a carefully selected fraction of the entire data set, the story is a bit different.

Looking at the NSIDC Arctic SIE data set, the September average for 1979 was 7.2 million sq km. Taking that as the starting reference, there have (thus far) been 7 occasions upon which a new record low has been set. These were as follows...

1984 (0.4%)
1985 (3.3%)
1990 (10%)
1995 (1.8%)
2002 (2.2%)
2005 (6.5%)
2007 (22.8%)

The number in parenthesis indicates how much was sliced off the previous minimum figure. The sheer size of the drop in 2007 should immediately scream "outlier" to anyone with even the most rudimentary grasp of time series data analysis. (Or even to anyone with an open mind.)

Those of the ostrich persuasion seem to gain particular comfort from the fact that 2008 and 2009 "recovered" progressively from the 2007 nadir, as seen below...

2007 4.3 million sq km
2008 4.68
2009 5.36
2010 4.9
2011 4.??

However, there is an old adage about "those who don't learn from history are doomed to repeat its mistakes." As has been stated on these pages many times, things are changing up North, but a similar pattern to that above can been seen below...

1990 6.24
1991 6.55
1992 7.55
1993 6.5
1994 7.18 (look, it's definitely recovering)

1995 6.13 (Oops, how did that happened?)

From the NSIDC figures, it can been seen that a new record low for September has been getting set about every 5 years. I am certainly not predicting that 2012 will be next, as it will depend on weather, not climate, when the record next falls.

However, I most certainly would not bet against 2007 being comfortably eclipsed in either 2012 or 2013. (I can't see it happening this year, but who knows?)

[Neven]

I still feel that 2011 melting season may just have one more trick up it's sleeve. Ice is still fragile. So fragile that one storm (mixing warm ocean water with surface ice/water) may do the trick.

This is definitely true, Rob. Like I say, I could very well be wrong. I'm still torn between what I learned last year, and how much things have (could) have changed.

I was a bit moody while writing this SIE update and it might have influenced my perspective. But you know, with those highs forecasted on the Siberian coast and lows everywhere else, we're looking at the perfect set-up for an early end to the melting season.

At the moment I don't think IJIS SIE will go below 4.5 million km2, but again, I could very easily be wrong. It's all down to the ice now.

[Neven]

The DragonballZ video is priceless and awesome.

A few videos representing the SSTs vs Ice is.

Thanks, Chris. Now you have me re-watching DBZ episodes. As if I have time for that. :-P

[Ned Ward]

Neven writes: I was a bit moody while writing this SIE update and it might have influenced my perspective.

You know, Neven, I for one really appreciate the straightforward and comprehensive way you do these updates. It's great to have everything in one place like this. Whatever happens this year, I sure hope you'll do this again next summer.

[Neven]

Thanks, Ned. There's a good chance I'll be covering next year's melting season, and probably do some more during hibernation as well.

[Seke Rob]

The fat lady has a stiff upper lip. JAXA adjustment from morning prelim just +1406 KmSq, fixing the 3rd on a -37,187 KmSq decline of extent.

On the minimum scales, most recent history [since 2005] has the 9th in 2008 as the date from which it started climb again i.e. 6 days to reach that date.

Yesterday JAXA gained 156 KmSq on 2007. The numbers to beat in the next 7 days are:

4th -51875
5th -43594
6th -37500
7th -10312
8th -23281
9th -13907
10th -32343

Current 2011 lag on 2007 is 103,594 KmSq, so with those daily numbers it's looking to be a tight fight.

Me current advanced model, GCR's, Planetary positioning of the gas giants, conjunction of moon and stars, sunspot anomalies. CME's, cracks in our magnetosphere, netting to the grand effect of not point not, has 4,415,152 KmSq to happen on 19th. Won't ask you to proof me I'm wrong... time will.

No CT update yet.

[L. Hamilton]

Rounding out the set of bar graphs, although it's not much of a time series I've been drawing one of the IJIS daily min too:
http://img.photobucket.com/albums/v224/Chiloe/Climate/sea_ice_JAXA_min_to_date.png

After two days rising, EB dropped on 9/4 and is once again slightly below 2007 for that date.

[L. Hamilton]

Department of typos: that should have been "too" and "UB".

[Michael Stefan]

L. Hamilton, as you referred to UB rising for a couple days, I believe that the rise it shows isn't real because when I looked at the map the other day I noticed anomalous areas of ice where there obviously wasn't any, especially a quite large area in the Sea of Okhotsk. CT also shows anomalous ice in Hudson Bay on the current map (9/2). Presumably, this is what is referred to when satellite error is mentioned; I wonder why they can't perform a "sanity check" to reduce errors (e.g. there should obviously be no ice in the Sea of Okhotsk right now).

[Paul Klemencic]

Preliminary September 4 Bremen map observations (changes from the Sept 3 final map):

The movement of the pack has changed once again, as a low pressure system now sits near the pole. The counterclockwise flow expanding out from the center, is pushing ice all along the eastside toward lower latitudes, pushing ice away from Severnaya Zemlya and into the Laptev, and pushing the expanded (split) Arm of ice in E. Siberian out toward the Siberian coast. Along with some spreading in the Greenland Sea, there shouldn't be a big loss of extent in these regions, with the possible exception of the E. Siberian. Although there was significant melt along the edges, and more expansion of open areas in the pack in some places, the fact the pack moved toward the Siberian coast spread it out over more extent area.

In the Chukchi and Beaufort, the pack was pushed inward, and compacted, leading to a loss of extent, but increasing ice concentrations near the edge.

When the final map is posted, I will update, and also include some observations on additional blink comparisons.

[Paul Klemencic]

Comments on the observations: That low over the north pole region, coupled with the high over Novaya Zemlya is doing a lot of damage to the pack by pushing ice toward the warmer seas, and blowing up (as in photographer darkroom use of this term) the ice in the E. Siberian. If this low stays in place in the same general area, the ice pack is going be dispersed all along the east side, and the East Siberian region will be pockmarked with open sea areas.

In the E. Siberian, already one group of floes with 90% concentration is surrounded by open water intermixed with mostly 50-60% ice around it, and is located too far away from the main pack to rejoin it (at 152E and 77N). This pod contains about 15k-20k sq km of over 70% ice, and there is at least 150k sq km of ice mostly below 60% between it and the main pack. In the area around this pod, we will eventually lose 150k to 200k sq km extent this year, if this low stays generally in place for another 24-36 hours.

In general, the pack is being moved back and forth, generally coming into contact with warmer seas, so the bottom melt is far from over. The weather still isn't cold enough to start the end of the melt season freeze cycle (water chilling, cold water settling down into the water column, and finally freezing at the surface) in a big way, in the regions with the vulnerable ice (Beaufort, Chukchi, E. Siberian, Laptev, and Greenland).

I believe the odds of falling below 4.25 million sq km on the Bremen report are higher than 60% at this point, for a new extent low by that measure (current Bremen extent is between 4.45 and 4.55 million sq km, according to the bar graph on Neven's Daily Graphs page.

[L. Hamilton]

Michael, thanks for your observation about the maps -- I only looked at the numbers. Regarding the need for "sanity checks," I think it also might be the case that on this blog we tend to over-interpret the day-to-day variations, which indeed go in different directions for the various indexes, for many different reasons.

But averaged over longer times the similarities are much more striking than the differences, for example in these time series of August means:
http://img.photobucket.com/albums/v224/Chiloe/Climate/sea_ice_time_series_Aug.png

Back to the day-to-day changes, though, I know the researchers behind these data sets are watching their own numbers even more closely than we are, and with even sharper interest.

[L. Hamilton]

Paul, you are correct that the most recent UB extent (9/3) is about 4.52. One caution about reading my bar graph, however: it shows the minimum for the year to date, which is not necessarily the most recent value. For UB the extent was slightly lower on 8/31, although rounding off to the same 4.5.

[Bob Wallace]

Obviously sea ice measurements are not exact. This is a complex system and measurements are going to be based on samples which brings all the impreciseness of sampling in any field.

Look at polls which ask political or social questions, they aren't "exact" but only approximations.

We are looking at daily estimates and treating the second decimal place as if it is meaningful.

Perhaps we need a more global index of ice condition. Something like averaging all the various extent measurements once a week.

(The downside of that is that it would take away a lot of the fun of watching the horses round the last turn and head for the finish line....)

[Espen]

88 N :

A refrozen "lake" at 88 N:

http://mgds.ldeo.columbia.edu/healy/reports/aloftcon/2011/20110904-1901.jpeg

Regards Espen

[michael sweet]

L. Hamilton:
On your graph of sea ice area, Cryosphere Today credits the NSIDC for the data. That is why the lines are the same for those two data sources. I would remove Cryosphere Today. Perhaps you could add a note saying Cryosphere Today is the same as NSIDC.

[Chris Biscan]

http://lance-modis.eosdis.nasa.gov/imagery/subsets/?subset=Arctic_r03c04.2011247.terra.1km

The ice there is diverging and completely falling apart right in front of our eyes.

quite incredible.

the clock is ticking on how bad this gets before refreeze.

[L. Hamilton]

Michael, so are the CT daily area values exactly the same numbers that NSIDC uses to calculate their own monthly areas? That wasn't obvious to me -- when I averaged the CT values by month they weren't identical to NSIDC published values (example below). But I'd like to learn more about this and get the graph right.

year,month,areaCT,areaNSIDC
2011,1,11.7887,11.69
2011,2,12.8302,12.63
2011,3,12.9388,12.71
2011,4,12.5732,12.36
2011,5,10.7827,10.65
2011,6,8.59992,8.45
2011,7,5.43387,5.30
2011,8,3.41473,3.31

[Paul Klemencic]

Chris Biscan, nice photo. You can easily see the stress cracks as the wind pushes the ice away from the pack.

Please give us direction where that is ? Looks like somewhere on the eastside, say near Franz Josef Land at about 75E and 83N?

[Ian Allen]

Paul,
Yes, that's definitely FJL on the right of the image.

[Kevin McKinney]

The IJIS SIE number for the 4th is: 4,644,531 km2.

Nearly 40k, significant loss for the time of year.

[Paul Klemencic]

Final Bremen map (August 4) observations: The low pressure system sitting near the pole has move now to just north of Severnaya Zemlya. The winds caused by the interaction of this low and the high sitting over Novaya Zemlya are continuing to shift the pack along the east side toward Svalbard, Franz Josef Land and toward the Kara Sea. On the other side of the low, a weak high pressure system on the Siberian coast inside the New Siberian Islands, is moving "the Arm(s)" of ice in the E. Siberian region toward the coast, pushing this ice away from the main pack. There is about 400k sq km of ice in the E. Siberian region below 80N.

There is little 90% concentration ice left in the Chukchi, which has about 170k sq km of ice left. Today there was a significant pullback of the ice edge in this region, as well as the Beaufort.

The preliminary IJIS number just came in at 4644531 for a 39k loss, on top of yesterday's final reported 36.8k loss.

If the weather conditions hold another day, a similar loss can be expected tomorrow.

[Bob Wallace]

2007 posted some larger melts for early September so even though today's melt was sizable 2011 lost a bit of ground.

[Steve Bloom]

I expect that may have been more compression than melt, Bob. In any event 2007 continues a pretty good pace of loss for the next 8 days or so, roughly 25k per day, and then pretty much dies on the vine. 2011 continues to have the potential to do something else, if the weather isn't entirely unfavorable.

[michael sweet]

L. Hamilton,
I am not sure how the data is processed. CT used to just credit NSIDC but now they credit several data sources. I would not be suprised if the NSIDC quality control checks the data for the monthly averages but not for daily data. The daily maps always show some ice in ice free areas (on the edges). They might also use pixel averaging and not daily averaging as described above for IJIS. CT gets the main picture from U. Bremen but CT changes the contrast from the U. Bremin site so it looks a little different.

I have noticed from comparing the Canade Ice Service maps to the U. Bremen site that U. Bremen usually does not show ice under 40% concentration, or even higher concentrations if the ice is broken up into small pieces (size 3 and 9 on Canada Ice charts). For example recently U. Bremen has shown the Parry channel as open on several days when Canada Ice Service shows 30-80% ice in many locations. The Articio photos confirm Canada Ice.

[Peter Ellis]

I vaguely recall that CT uses SSM/I data for historical area measurements, but recently switched over to AMSR-E data after a series of sensor failures on the SSM/I satellite, presumably with some cross-comparison and adjustments to allow them to combine the two series. NSIDC have stuck with the SSM/I data to maintain historical continuity. If so, it may be that CT/NSIDC used to agree more precisely but no longer do so: is this the case?

Regarding how NSIDC generates its monthly averages, I suspect it's pixel averaging. My main reason for saying this is that they also generate maps showing the median ice edge for each month, which is only possible if they're looking at the data on a per-pixel basis.

[L. Hamilton]

Michael, it seems non-redundant then to keep in the graph the information that NSIDC and CT areas are very similar but not identical.

[L. Hamilton]

Differences between NSIDC monthly area and average area calculated from CT daily show several patterns. The following refer to
diff = (monthly areaNSIDC) - (monthly mean areaCT)

* Mean diff for the whole series is about -64k (CT significantly higher), with no time trend.

* SD diff for whole series is about 186k, but decreasing over time (less variation, although no change in bias, in recent years).

* Median diff is about 0 in Aug, positive Sep-Dec, and negative the rest of the year (pronounced seasonal pattern).

So the differences aren't random, but I'd welcome enlightenment.

[Wipneus]

IJIS extent update: 4655156, up 10,625 from this morning.

[Peter Ellis]

L. Hamilton, do your observations change depending on whether you use the mean or median monthly value for CT area?

[Peter Ellis]

For the seasonal comparison, it might be more helpful to look at the anomaly relative to the mean diff. It looks like doing that would yield a seasonal pattern almost identical to the normal yearly cycle.

[michael sweet]

L. Hamilton,
I like your graphs a lot. They sumarize some of the key data in a clear readable way. Put in what you think is best.

[Espen]

North East Greenland / Joekelbugt:

Have you watched the mess around Joekelbugt recently?
http://rapidfire.sci.gsfc.nasa.gov/imagery/subsets/?subset=Arctic_r02c03.2011248.aqua.250m

Reards Espen

[Christoffer Ladstein]

Christ! The "Hole" in the laptev sea have "flash"-melted from one day to the next...
http://www.iup.uni-bremen.de:8084/amsr/arctic_AMSRE_nic.png

[Neven]

Whoa, that is indeed big. Thanks, Christoffer. I'm writing a post right now.

[Christoffer Ladstein]

Just a pleasure, Neven!

This melt shouldn't come as a BIG surprise considering the SST in The Laptev Sea, which has been SEVERAL degrees above normal for almost 2 months, and as the hourly pics from Healy do show, the temps even close to the pole have been on the up-tick lately after a short dip down to -10 C.

But I be mighty surprised if neither you, Neven nor Paul K./ Chris B. will "find" a strong Low pressure or similar, to explain what's going on at those latitudes...

No matter, tomorrows drop will be roughly 50K, or more?!

[Michael Fliss]

Oh my gosh, Espen! What a brilliant, beautiful image. It breathes life into UB's Polar View of the Greenland Sea. The ice-the Arctic-speaks to us...and anyone who has walked on ice will recognize that voice.

[Daniel Bailey]

I don't know about you, but this is the voice I'm hearing:

http://www.jahozafat.com/php/sounds/?id=bst&media=WAVS&type=Movies&movie=Wizard_Of_Oz&quote=oz9.txt&file=oz9.wav

[Espen]

Michael,

Anyone who listened to the sound of ice calving they know it is such a loud, impressive, frightening sound U willnever forget, I must have a been Rock Concert up there, could only imagine how it must have when Petermann calved last year in between those rock walls in the Petermann fjord!

regards espen

[Michael Fliss]

Ha ha! I like that Daniel. Regardless, and as we all know, unless we change our destructive ways the witch's scream will be our death rattle...not earth's. Now, back to stats and predictions!

[Christoffer Ladstein]

Slightly OT (until later this month?!): The Hurricane Katia is GROWING very FAST, looks like the East of USA will be beated hard again. Is this nature's revenge upon the lack of will of those well paid Senators at Capitol Hill....

http://sailwx.info/hurricanes/stormreport.phtml?stormnum=665

[Espen]

Message to Paul Klemencic,

Do you remember you gave some area figures on the 15-degree quadrants between 70 - 75 N ,75-80 N and 85-95 N? Could I please get those figures again.

Thanks Espen

[Chris Biscan]

the hurricane is progged to miss the the East Coast by 100 miles.

and even though I am a liberal who has no patriotism. Like most American's in general these days. writing what you wrote is pretty bad. Most Americans are good people conservative or liberal, black, white, brown, or blue it doesn't matter. They don't deserve revenge because some politicians are dirty in a system flushed with money and greed.

That makes this site look bad.

[Espen]

To Paul,

Forget about the numbers, I just found them.

Regards Espen

[Espen]

With what is still happening in the Arctic Sea, because the situation is very unlike 2007, I believe there is still a potential of loosing between 400 - 500 km2 by the end of this melting season.

Regards Espen

[Bob Wallace]

400km2 would set an all time record.

500km2 should open a few eyes and pile another warning sign on top of all the droughts, fires and floods of the last couple of years.

Currently the seven day average for 2011 is running ~17k higher than the 2007 average.

It could happen....

[AmbiValent]

I think a loss of 500km2 is almost certain. But I suspect you both meant 500 thousand km2.

[Espen]

Ambi,

Yes I did! Thanks

Regards Espen

[Christoffer Ladstein]

Chris B:

I did NOT mean to offend you or your fellow american citizens in personal, BUT there must be something rotten in your system to be able to get so close to an economical "collapse"?!
I just finished "The Road", and though I can't say that we'll end up there just because of the vanishing ice at our poles, I don't think I'm wrong in saying that most of the readers and contributors on this blog is above normal interested in Mother Earth well being...

So just don't give a damn about all that us, the Europeans write, we tend to offend americans quite easily. You might say that if we didn't you ought to have reason to get worried!

[AmbiValent]

Looking at the pictures from the Healy, currently around 88N 176W, the ice looks like it's barely out of the water. Would I correctly guess that it's less than a meter thick?

[crandles]

Northern Greenland seems to have had a good covering of snow - there is quite a contrast on modis between today and clear pic 11 days before.

[AmbiValent]

Crandles:
Wouldn't such a snow cover speak for temperatures barely below 0C; wouldn't such temperatures be atypical for Northern Greenland even at this time of year?

[Bob Wallace]

Christoffer, there is something rotten in our system. It's run by humans.

Being humans, we're gullible and when someone offers us free candy we hold out our hands.

Reagan came to office saying that we could cut taxes and regulations and it would make us all rich. Sounded good, so we gave it a try.

Really not unlike the 1920s when industries and banking were not regulated. It might be a lesson we have to learn every few generations.

[Chris Biscan]

The republican party has gotten many religious and lower middle class by the balls of manipulation.

While the Democrats have caved and caved and recently been bought out as well.

Americans are easily bought and distracted.

very sad.

[Chris Biscan]

My hometown "family weather blog" has multiple posts saying the Earth is only 6,000 years old.

half our country believes that.

[Chris Biscan]

UB FINAL

had a major losses all over the arctic.

[Kevin McKinney]

Tonight, the fat lady is humming "4,610,469 km2."

Tomorrow noon will likely be a slightly different tune.

[D]

Not to take things too far off topic, but the last few posts raise a philosophical issue.

First of all, Katia will not hit the US, so we are discussing hypothetical disasters here.

Climate change is going to increase the incidence of extreme weather events in the future(and probably in the present as well). The simple way to think of this is of a loaded pair of dice. No specific event was caused by CC, but each specific disaster was made somewhat more likely by it.

There are those who say that we should never point out that a specific event was influencedd by CC, out of decency, accuracy or whatnot.

This seems disingenuous to me. Never admitting specific damage caused by climate change is exactly what the climate deniers would want. Instead, I think we should start identifying those disasters that were made more likely by CC(assuming the science is better than speculative).

Obviously there shouldn't be any morbid celebration over the suffering of others. But on the other hand, people need to be constantly reminded of the practical consequences of global warming because there are far to many people who are in complete denial.

[www.google.com/accounts/o8/id?id=AItOawkpUaD_uYjZAIrhpA6AA5KyEs-CSoL4zlM]

There is a news on the german site of Alfred-Wegener-Institut about the possible new negative record of summer sea ice cover:

german link:

AWI: Ein neuer Minusrekord kündigt sich an

Same link translated with google:

AWI: A new negative record announces itself

Chris K

[Chris Biscan]

http://www.iup.uni-bremen.de:8084/amsr/ice_ext_n.png

Bremen plummets.

[Chris Biscan]

http://ocean.dmi.dk/arctic/satellite/plots/satanom.arc.d-00.png

early DMI sat temps show a possible big day coming up on the 6th.

recede in the Greenland sea, beaufort, ESB

[Ned Ward]

Kevin McKinney writes: Tonight, the fat lady is humming "4,610,469 km2."

Guess this week's opera must be Einstein on the Beach....

:-)

[Neven]

I have updated the Fram Strait, Slush Puppie and Flashbite animations.

[Chris Biscan]

http://ocean.dmi.dk/arctic/plots/icecover/icecover_current.png

Watt's used that graph to say the ice was recovering in 2010.

A poster on Americanwx also used it recently when it was "better" to say it was a much better indicator of the state of the sea ice. Guess they won't be using it.

I guess that means Norsex is the last hope of the ones trying to trick folks into believing the ice is ok.

[Nick Barnes]

Re areas of zones, sectors, boxes, etc:

Archimedes' hatbox theorem tells us that the area of a latitudinal zone (i.e. all the area between latitudes A and B) is 2.pi.R^2.(sin(B) - sin(A)). The earth's polar radius is approximately 6360km, so the constant part there is 254e6 km^2, and I'm being overgenerous by giving three sig fig. The sine table looks like this:
75 0.965925826289
80 0.984807753012
85 0.996194698092
90 1.0

So the 75-80 zone is 4.8e6 km^2. The 80-85 zone is 2.9e6 km^2. The 85-90 zone is 0.97e6 km^2.

To get 15-degree chunks of these, obviously divide by 24 (i.e. 200e3, 120e3, 40e3, near enough).

I've shown the working so readers can do any related computations themselves.

[Kevin McKinney]

Ned Ward, you must have a Glass ear. . .

;-)

[L. Hamilton]

Updated to 9/5:
http://img.photobucket.com/albums/v224/Chiloe/Climate/sea_ice_UBN_min_to_date.png

[Neven]

Larry, how big was the last daily drop? I ask because of the small flash melt in the Laptev Bite.

[L. Hamilton]

9/3 to 9/4, -27k
9/4 to 9/5, -114k

[Ned Ward]

Ned Ward, you must have a Glass ear. . .

;-)

We could fill up this thread with puns ...

... but puns are a rather minimalist form of humor.

;-) back atcha.

[Paul Klemencic]

L. Hamilton, thanks for the information. Noted, and adjusted my running total from last observation. And very consistent with the big pack changes observed yesterday. The 6.5km grid is definitely picking up open water the bigger 12.5km grid is still missing at this time, given the 4x area, and given the unconsolidated state of much of the ice. IJIS is going to be the last domino to fall into line, but will converge fast to Bremen, when the compaction stage really begins.

Chris Biscan, so far the compaction has been limited mostly to the Beaufort, and to a lesser extent, the Chukchi region. The E. Siberian is still spreading and melting, as well as the Laptev Bite area. When we do see compaction in the E. Siberian, the resulting loss could be very impressive and fast.

Nick Barnes, thank you for the info on the equation to get areas within each quadrangle at between 75N and 80N at around 200k sq km, and 80N to 85N at around 120k sq km.

[Ned Ward]

9/3 to 9/4, -27k
9/4 to 9/5, -114k

L. Hamilton, I'm sorry if you've answered this before, but can you say anything about the origin of those numbers? Are they from adding up the 15+% extent grid cells in the Bremen maps? If so, are they the maps from the ASI algorithm or the Bootstrap algorithm? Using the NSIDC map projection or the "180" one?

I've tried doing this, and get very different numbers. For example, using the ASI algorithm maps with the NSIDC coordinate system, I get the following:

3 Sep: 4.459922
4 Sep: 4.413906
5 Sep: 4.351055

But using the ASI algorithm maps with the "180" coordinate system, I get the following:

3 Sep: 4.449922
4 Sep: 4.390859
5 Sep: 4.297148

I sure wish there were some official numbers somewhere that I could check my work against. I'm probably doing something wrong, perhaps multiple things wrong.

[www.google.com/accounts/o8/id?id=AItOawkpUaD_uYjZAIrhpA6AA5KyEs-CSoL4zlM]

NSIDC is online again.

Chris K

[L. Hamilton]

Ned, I'm not calculating SIE myself, but watching the daily values calculated by UB. These aren't my data to share, and I've promised not to publish them (the PIs have new reports in the works). Still, I try to post a note here when I see something interesting. Sorry if those notes seem cryptic!

BTW, y'all can call me Larry.

[Ned Ward]

OK, thanks, Larry. "Cryptic" is perfectly fine, especially if the alternative is no numbers at all!

:-)

[Christoffer Ladstein]

The days of "smoothie" ice and smooth sky has finally come to the north-eastern corner of Greenland, and as the picture below so clearly tell: Almost all landfast ice is now GONE! Churned away, and perhaps even more will go until King Winter returns for real!?

http://lance-modis.eosdis.nasa.gov/imagery/subsets/?subset=Arctic_r03c03.2011249.terra.250m

[Christoffer Ladstein]

At least compared to the same area 29 days earlier, the landscape barren and free for snow, but still in the "grip" of landfast ice!
http://lance-modis.eosdis.nasa.gov/imagery/subsets/?subset=Arctic_r03c03.2011220.terra

Those with more time-spanning memory are perhaps aware of how frequent this occur?!

[Twemoran]

Christoffer - I think the ice shelf that you are referencing, the one in front of Independence Fjord, has been in place for some thousands of years. It opened up after the last spring tide.

I just came across the term 'piteraq', Google it for some scary stuff!!

North East Greenland may be set for these windstorms as we speak - 50 to 80 m/s equals
180 to 288 Kilometers per hour or 112 to 189 miles per hour.

I assume that these winds would follow fjords and may not be picked up by weather stations, but the damage done to any remaining fast ice could be extensive.

[www.google.com/accounts/o8/id?id=AItOawkpUaD_uYjZAIrhpA6AA5KyEs-CSoL4zlM]

NSIDC has just released its August analysis ->

http://nsidc.org/arcticseaicenews/

sorry for posting it in an extremly old thread first....

Chris K

[Neven]

Thanks, Chris K (what were you doing in Open Thread 3, haha).

NSIDC is offline again. Hmm. Well, I'll start preparing a post then.

[Neven]

BTW, folks, sorry for not diving into that fast ice on the Northeast coast of Greenland. Usually when I go have a look in the MODIS archive (a bit of a PITA to be frank) I find out these things have happened before. But maybe this time is the first time for a very long time. I might have a look one of these days, and if it is exceptional, turn it into an animation.

Here's a current SLP map from DMI:

We see that big low to the west of Norway (noticing anything from that, Christoffer?) that is going to come up towards the Arctic in the coming 2-3 days and should increase transport towards the Atlantic.

But there's a smaller low over the Lincoln as well that should simultaneously push the drift and fast ice away from the Northern Greenland coast (possibly helped by those katabatic winds), and finally push some ice into the channels between the Queen Elizabeth islands.