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 graph webpage for daily updated graphs, maps and live webcam images.
July 2nd 2011
Another month and another summer solstice has passed. Despite somewhat of an anticlimax at the end of June with two days of very low reported extent decreases, the month has had a very decent daily extent decrease of 66K, second only to 2010's free-falling June (74K daily SIE decrease).
The sun is burning hot and long right now in the most northern part of the planet. The only thing that can prevent the rays reaching the floating ice masses in the Arctic ocean is clouds. The amount of clouds in the Arctic skies is determined by the presence and distribution of high and low pressure areas. These also determine which way and how hard the wind is blowing.
It was a lack of clouds and winds blowing the 'right' way during July - and much of the rest of the melting season - that made 2007 the stunning record year it was. The exact opposite happened last year, ending the record melting so far. June 2011 saw quite a few well-placed high-pressure areas, but as I will show below a slight shift in sea level pressure distribution had direct consequences.
Obviously I will focus a lot on sea level pressure this month, as it largely determines whether July fulfils its potential of mega-melting.
Sea ice extent (SIE)
Here's the current IJIS SIE graph:
The little deviation from the downward trend can clearly be observed. This was due to two days of just 30K reported extent decreases, which was less than half the daily average for June. The 2011 trend line is nonetheless still in the race, even if 2010 has consolidated its lead and 2007 is seriously getting fired up.
The current difference between 2011 and the other years is as follows:
- 2005: -553K (-83,709)
- 2006: -176K (-70,025)
- 2007: -226K (-98,608)
- 2008: -660K (-81,068)
- 2009: -660K (-92,127)
- 2010: +256K (-62,601)
Between brackets is the average daily extent rate for the month of July. 2011's average daily extent rate for July is currently -85,156 square kilometers, but I wouldn't call it an average, as only 1 day of extent decrease has been reported by IJIS so far.
The rate on the Uni Bremen extent rate graph showed a bit of an uptick as well. It will have to start going down hard if this year is to keep up with 2007:
Sea ice area (SIA)
The rate of SIA hasn't slowed down as much as that of SIE, and so the anomaly on the Cryosphere Today SIA anomaly graph is still hovering around the -1.5 million square km mark:
Sea ice area in the region of the East Siberian Sea has been dropping pretty fast lately. The effect of the Beaufort Gyre was showing up nicely in the Laptev Sea SIA graph, but as the Beaufort Gyre has apparently stalled again in the past few days, the decrease in the Laptev Sea SIA has stalled too. Pretty much everywhere else there is a steady decrease (Hudson Bay is about to empty out), the Arctic Basin SIA has started to drop as well.
Cryosphere Today area per IJIS extent (CAPIE)
With SIA droping faster than SIE this year's trend line on our CAPIE graph has gone down quite a bit to join 2007, 2008 and 2010. Melt ponds have something to with the percentage going down, but the ice pack spreading out a bit the last couple of days (causing SIE decrease to decrease) definitely influenced the steep drop at the end of the month:
Sea Level Pressure
Like I've said in the introduction high-pressure areas were dominating the Arctic in June. NOAA's Arctic Oscillation Index shows this clearly:
The AO was becoming less negative a week ago, which immediately resulted in lower extent decreases. Luckily I've been saving images from the DMI Centre for Ocean and Ice. This animation shows what happened in the past week:
There was a high-pressure area over the Beaufort Sea that got pushed towards Siberia by a low-pressure area over Canada/Alaska. I think this has caused the ice pack to spread out, which is why extent numbers have decreased more slowly for a couple of days.
The question now of course is what will happen the coming week. According to the 7-day forecast for the Arctic Oscillation index the AO will turn more negative again. This is also reflected in the ECMWF weather forecast maps for the coming 5 days:
A rather big high-pressure area is going to form more or less over the centre of the Arctic Ocean. Although it isn't centered in the Beaufort Sea (a prerequisite for the Beaufort Gyre) it should cause some winds and transport of ice toward Siberia. And clear skies of course.
Update conclusion
I think we are going to see above average melting the coming week, perhaps even some century breaks. I base this on that large high-pressure area bringing clear skies over much of the Arctic and winds pushing the ice towards warm Siberia. And of course, there is still some ice left in Hudson Bay that is probably going to disappear rather rapidly, making a mark on SIE decrease.
If this keeps up, July has a good chance of doing justice to its newly invented nickname: the month of mega-melt. But there is no way of knowing, things could just as easily and drastically switch as they did in 2010. Nothing in the Arctic is a dead certainty.
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TIPS - Other blog posts and news articles concerning the Arctic and its ice:
MSNBC has this on a new paper by James Overland and Muyin Wang that is about to be published in GRL: Dramatic Arctic sea ice shrinkage predicted
From Earth Times: Arctic sea-ice loss lets Pacific sea-life into Atlantic
And more from MSNBC: Warming oceans could melt ice faster than expected
With seasonal lag in the arctic being about three weeks after summer solistice, tempertures will start to head back down from their climate highs (in theory).
At some points, heavy cloud cover provides an insulation to keep the heat in.
I'm not sure where in the time scale, the advantage switches to clouds. I was thinking around the time that the DMI North of 80 Climate graph hits freezing.
Any ideas ?
It would also be interesting to see the AO graph for the summer of 2007. Did anybody keep one?
Posted by: Lord Soth | July 08, 2011 at 12:17
Haven't got a detailed graph of AO but monthly average numbers were:
2007 1 2.033800
2007 2 -1.306900
2007 3 1.182100
2007 4 0.544270
2007 5 0.893670
2007 6 -0.554960
2007 7 -0.396520
2007 8 -0.033738
2007 9 0.178920
2007 10 0.383480
2007 11 -0.518660
2007 12 0.821130
They could be graphed if you wanted.
For comparison this years numbers are
2011 1 -1.683100
2011 2 1.575400
2011 3 1.424100
2011 4 2.274800
2011 5 -0.035093
2011 6 -0.857750
Posted by: crandles | July 08, 2011 at 12:29
Here is an interesting paper by Wang on the interaction of the AO and DA, to create conditions for extreme sea ice loss.
http://psc.apl.washington.edu/zhang/Pubs/Wang_etal2008GL036706.pdf
We can tell this year visually that we have a postive DA, but im not sure if anybody keeps a daily or weekly index of the DA like they do with the AO.
Posted by: Lord Soth | July 08, 2011 at 12:39
It's a little intimidating for this lurker who is struggling to wade through the math and the science. So, first of all, thanks to all of you whose posts are engaging, enlightening and (often) funny.
And now a query. For centuries, the idea that skirting the permanent summer pack via the narrow and navigationally difficult NW Passage was the hoped for maritime 'short-cut' between Asia and Europe. Given the pattern of rapid reduction in extent and the deeper water offshore, does not the NE Passge (i.e. north of Russia) to the icefree port of Murmansk seems a more likely route for significant traffic? I realize both were 'open' the last couple of summers but 'open' for small vessels isn't the same as a feasible route for significant maritime traffic. Thanks in advance.
Posted by: Voyageur | July 08, 2011 at 13:34
Voyageur: the "Northern Sea Route" is the usual name for what you call the "NE Passge". It was used extensively for shipping, in convoys escorted by ice-breakers, in the Soviet era. It has been used for commercial shipping in the last two years, and probably will be again in 2011.
In terms of usability, without ice-breaker support, it looks about the same as the deep-water route of the North-West Passage.
Posted by: Nick Barnes | July 08, 2011 at 14:51
See http://www.rzd-partner.com/news/2011/07/05/367327.html for instance.
Posted by: Nick Barnes | July 08, 2011 at 14:55
Nick, appreciate both comments and was aware of the soviet convoys (actually saw one leave Murmansk back in the 80s) ... but I take it that you think the deep-water NW Passage route will be as "ice free" or not as the NSR with the retreat of the cap; i.e. that the ice will not linger longer in the Cdn archipelago
thanks
Posted by: Voyageur | July 08, 2011 at 16:23
Hi all,
Just to note that the CT global sea ice anomaly is now over 2 million, which is a rare event.
I have the impression that the current weather pattern, with the extreme high nearly over the Pole, is absolutely hammering the main pack, without this showing up so much on the area and extent figures yet.
Melt in 2011 seems to be ahead of both 2010 and 2007; and in both of these previous maga-melting years, the "low-hanging fruit" in the Hudson Bay had already pretty much vanished by now. So I put 2011 even further ahead.
Posted by: idunno | July 08, 2011 at 16:26
Daniel Bailey/
Webcam #1 is running fine. Sometimes you must go to their archive to get the latest image. It's just the quick-link on the home page that are not up to date.
Latest Cam#1
Posted by: www.facebook.com/profile.php?id=687386516 | July 08, 2011 at 16:37
...or press F5 while on the page where the thumbnails are.
Posted by: www.facebook.com/profile.php?id=687386516 | July 08, 2011 at 16:40
No, webcam #1 isn't a happy bunny. It should be uploading photos every 8 hours, but it's skipped at least half of it's "slots" over the last couple of days. Could be any number of things: problem with the satellite uplink, battery issues etc.
If you look at the last couple you'll see that #1 is also beginning to fall backwards just like #2.
Posted by: Peter Ellis | July 08, 2011 at 16:48
I believe we just had the first revision downwards. Just 313 square km, but still.
Posted by: Neven | July 08, 2011 at 16:59
You're in denial Peter. And I don't want to check if the pictures are there or not, because I know everything is fine.
:)
Posted by: www.facebook.com/profile.php?id=687386516 | July 08, 2011 at 17:01
Indeed, idunno. PIPS is showing a nice clockwise churning of the ice pack, but the arrows aren't huge or anything. So while insolation is hammering away, winds perhaps aren't that mega.
The global SIA anomaly is mainly caused by a huge anomaly in the Antarctic SIA. But if Arctic SIA has a couple of big century breaks in a row...
Posted by: Neven | July 08, 2011 at 17:15
Small milestones department, northern sea ice extent now appears to be lowest for this date over the satellite record.
Posted by: L. Hamilton | July 08, 2011 at 17:57
Hi Neven,
In the first Terra satellite images of 8 July, there seems to be a big break-up of the ice North of Ellesmere island, a little too close to the Ward Hunt Ice shelf for comfort?
It looks to me to be a little to the North, but that's a guess, and I thought somebody here would know...
Posted by: idunno | July 08, 2011 at 20:44
Ice Watchers: Here are some points affecting the near-future prospects for IJIS SIE:
- In 2007 the rate of decline in IJIS SIE hit bottom on July 9/10 (as ranked by the 30-day running average) with both days tied at -104,708 km^2 / day
- the 7-day moving avg for -SIE today is lower (greater loss rate) than the next 7 days in 2007
- DMI.dk SIE (which uses a 30% SI concentration cutoff) reached a record low 6.00 million km^2 today
- IJIS reports 8.37 m at a 15% cutoff meaning there is about 2.37 m km^2 of Sea Ice extent in the range of 15% to 30% concentration
- further, DMI.dk SIE extent fell approx 180,000 km^2 yesterday, indicating a rapid change for SIE at the 15% threshold in days to come.
- the AO index is now at -2.0 (month-to-date avg is 1.5), both of which are below the July 2007 average of 0.4
- AO index is a proxy for Solar insolation, with lower AO values indicating more SW radiation reaching the SI surface.
In summary, I expect record loss of IJIS SIE in the short term. I will update this prognosis when Baffin and Hudson Bay have gone to zero SIE.Game on!
Posted by: Artful Dodger | July 08, 2011 at 22:07
I should add that the early break out of land fast ice off Barrow,AK may indicate anomalously warm Sea temperatures, since the early break out was not predicted by estimates based on Solar Insolation and grounded pressure ridges.
Note that Heat flux through the Bering Strait was a major factor in the record low SIE measured in September 2007.
Posted by: Artful Dodger | July 08, 2011 at 22:12
I'd be wary of interpreting the Barrow data as indicating elevated sea temperature. My understanding is that the whole point is that the grounded pressure ridges isolate the landfast ice from the sea circulation and thus eliminate this as a factor.
Barrow had very early melt pond formation this year - which to me implicates factors above/within the ice rather than below it. Whether that's air temperature, solar radiation or other factors such as dirt/sediment in the ice, who knows?
Posted by: Peter Ellis | July 08, 2011 at 22:53
idunno: the Ward Hunt Ice Shelf is at the far east end of that lead. It's a long rectangle, parallel to the coast, a darker colour than the sea-ice.
Posted by: Nick Barnes | July 09, 2011 at 00:16
Jul 08, 2011 prelim SIE:
8,217,031 km^2
Daily change in SIE:
-149,844
Posted by: Artful Dodger | July 09, 2011 at 05:10
Another 149,844 sq km extent loss on IARC-JAXA for 7/8/11.
2011 is deciding to taunt 2007, and go for the championship belt.
Posted by: Anu | July 09, 2011 at 05:43
I imagine most of you will have seen this post "Arctic sea ice in record retreat" on
http://www.wunderground.com/blog/JeffMasters/show.html
and 'Arctic Death Spiral' on Joe Romm's Climate Progress with a plug for your blog, Neven? as "a must for cryo-junkies"! That's us!
This is for Lodger, http://make-everything-ok.com/
and The (Petermann) ice Island off Labrador:
http://earthobservatory.nasa.gov/IOTD/view.php?id=51264
with a link to neat video from some fishermen of part?of it.
I cant contribute much constructive here but greatly enjoy all you write & mostly manage to follow the science, & even the maths too sometimes!
I have been delighted to make a donation to the Tip Jar, feels like the best value 'movie ticket' I've ever bought, in a front row seat & enjoying the very best company & conversation.
Thanks to Articio for the Healy webcam video, feels like realtime up there on the bridge! & easier than clicking my way through their jpg files.
Apologies & OT now I know, Neven:
I just try to make 'art stuff' = textiles, inspired by my concerns about all of this. And I want them to be underpinned by accurate science.
Two of my pieces are currently showing in the Celebration exhibition here in Kentucky USA,
"Warning & Warning 2 = warning flags with an artist's statement alongside about loss of sea ice in the arctic & antarctica.
They can be seen in side view in the last image:
http://www.quiltmuseum.org/current-exhibits.html
This didn't seem like the best venue for a work about climate change but then I found at the time it opened the Ohio R (meets the Mississippi just downstream) was in high flood one block away behind their flood protection barriers. Not sure if viewers would have 'joined the dots' tho?!
Clare, in winter in NZ
http://www.clareplug.vc.net.nz
Posted by: Clare | July 09, 2011 at 08:07
As pointed out by Andrew, it looks like ice leaving through Fram straight is higher than normal.
And as pointed out by Lodger, Hudson bay is approaching 15% concentration, and will thus fall off the edge for IJIS, meaning that the next few days we will see more century breaks.
On top of that, the Kara sea has been warming relentless over the past couple of weeks of clear skies, knocking out ice North of Siberia at record pace (open ocean now approaching 85deg.
Meanwhile, the central basin has been hammered with alternate rain (melting top snow) and brutal clear skies, resulting in melting ponds the size of small lakes witnessed by the NOAA North Pole cameras.
We are at record minimum extent and ice melt shows only signs of accelleration as Nature does her brutal high-summer Actic
And now the Chukchi sea (my favorite), left behind in extent reduction by heavy cloud cover over the past few weeks, is clearing. More Arctic solar heat absorbed by the dark ocean, which will have no mercy with the already bad (witnessed by Healy webcam) ice in the area. If that high pressure zone maintains for a week or so, I predict extreme ice annihilation around the Chukchi sea and deep into the Arctic Basin as a result.
Guys, what an amazing, historic melting season ! Exciting and humbling and scary at the same time.
Posted by: Rob Dekker | July 09, 2011 at 09:58
The dmi 30% graph is really in freefall now
http://ocean.dmi.dk/arctic/icecover.uk.php
Likewise camera 1
http://www.arctic.noaa.gov/latest/noaa1.jpg
This year is aiming to be special
Posted by: Derek | July 09, 2011 at 10:47
For IJIS extent, 2011 is 2 days ahead of 2007 today. 2007 lost insane amounts of ice in July, so I'm expecting this lead to disappear in the next couple of weeks.
Posted by: Nick Barnes | July 09, 2011 at 13:16
Nick: Why do believe that? The path 2011 has taken is more or less under the 2007 figures all way, and then add the heavy volume loss in the meantime. My own estimates of extend/area (based on mainly Modis)the real figures are even lower than most sources indicate. But of course something could change, but the potential of less sea ice in 2011 than 2007 is very possible.
Espen
Posted by: Espen | July 09, 2011 at 13:32
Webcam1 hai, hai...
Posted by: Paolo | July 09, 2011 at 14:37
Only hours left, webcam # 1 is going down the drain very soon: http://www.arctic.noaa.gov/npole/2011/images/noaa1-2011-0709-101118.jpg
Espen
Posted by: Espen | July 09, 2011 at 14:37
Do anyone have information on how far apart the 2 Northpole webcams are? It must be some distance since the weather sometimes looks very different from one to the other?
Espen
Posted by: Espen | July 09, 2011 at 15:39
The current positions of the webcam plus weather can be found at the NPEO website.
http://psc.apl.washington.edu/northpole/
Webcam 1 is associated with the IABP PAWS Buoy
Webacam 2 is associated with the POPS-12 Buoy
The chart is updated every few weeks, but the position and temperture is provided several times a day.
Posted by: Lord Soth | July 09, 2011 at 16:26
I always think it's interesting the internal temps of these cameras, 6.5c even up to 13c recently. Doesn't match the air temperature from the bouys but gives me a sense of the effect of the sun on a plastic box therefore the heating energy of the sun up there at the moment. Not very scientific but interesting and compares to -17c in April.
Posted by: Phil | July 09, 2011 at 17:48
Phil there is internal heating to keep the cameras working which has been discussed here a couple of times.
Posted by: crandles | July 09, 2011 at 18:12
Espen: it's just my hunch. The central pack seems more solid to me than in 2010 or 2007. The 'frappuccino' look has not yet set in. My gut feeling is that the central arctic is just not going to melt out in that way this year. Maybe the ice is thicker? We'll see.
(by the way, was I the first person to call it 'frappuccino'?)
Posted by: Nick Barnes | July 09, 2011 at 22:36
@Rob Dekker - a belated thanks for the explanation :) - w
Posted by: Wayne Kernochan | July 09, 2011 at 23:12
Thanks Lord Soth, for pointing out the position of the NOAA webcams. I’ve been looking for that, because the lead showing on 2 is on the brink of being visible on MODIS. That is, given clear weather. And it isn’t.
Since day 183 I couldn’t renew a count on my study area north of Greenland. But webcam 2 is only a tantalising 185 km north of my area's limit.
From the sparse MODIS info, I get a hunch the area is getting compacted up to north Greenland.
If that’s what Nick Barnes takes as a sit for the central pack, he’s right FTTB. But the compaction isn’t yet closing the lead near webcam 2. And Nick, your ‘frappé’ sure was there, day 183 (last time well visible).
But as usual, action shifts in the Arctic. Ostrov Wrangelya is now allmost ‘freefloating'. Hot weather being forecast for the East Siberian Coast (24 dC in Tiksi), soon all fast ice there will be gone. Within a week, the central pack will have no attachment left to Canada, Alaska nor Siberia.
Posted by: Werther | July 10, 2011 at 01:27
I'm not sure about 2007, but last year the ice pack had spread out a lot. If things stay like they are now, I don't think we'll be seeing many holes around the North Pole either. But I'm sure/hope Werther will analyze this thoroughly when the time is there.
Posted by: Neven | July 10, 2011 at 15:56
@Nick: I agree on central pack being intact, and I can agree with you here. Nevertheless, and it is actually my question: could it be due to relatively still weather. Last year, we've seen a lot of cyclonic activity, which broke ice up, this year, winds may not be so strong and therefore, no fragmentation occurred yet ? Or, ice has rebuild a little bit and PIOMAS and TOPAZ models are underestimating volume for the time being ?
But either way. Maybe 2007 was really specific and we have some more years to watch ice disappearing (until 2030). But, even if this is true, the melt is in my point of view extremely rapid. Hey, whole Arctic ice gone within much less than a century - this is like a millisecond in a human life, comparing to ordinary climate change periods (figuratively, not exactly, if someone can give us a real value, it would be nice to know).
Posted by: Patrice Pustavrh | July 10, 2011 at 16:49