Another month has passed and so here is the updated Arctic sea ice volume graph as calculated by the Pan-Arctic Ice Ocean Modeling and Assimilation System (PIOMAS) at the Polar Science Center:
As I wrote last month:
It all depends on the weather in the coming weeks, of course, but according to the forecasts anomalously warm temperatures and clear skies are persisting in the short term, and so I wouldn't be surprised if 2015 overtakes 2014 (which lost incredibly little volume during July), comes closer to 2013 and starts closing that enormous gap with 2012.
This is exactly what happened, as the past month turned out to be the warmest and sunniest July in the 2006-2015 period (I'll have more on that in the upcoming July analysis). Volume dropped by 6659 km3, the second biggest drop in the 2006-2015 period, slightly less than 2009, slightly more than 2007 (here's a comparison with both years).
And so 2015 overtook 2014 and is now 971 km3 lower, the gap with 2013 went down from 1223 to 809 km3, and the huge gap with 2012 has become around 30% smaller (from 2968 to 1928 km3).
Here's Wipneus' PIOMAS volume graph:
This also means that the trend line on the PIOMAS sea ice volume anomaly graph has dipped a bit further below the linear trend:
After crudely calculating the ice pack's average thickness by dividing PIOMAS volume numbers with Cryosphere Today sea ice area numbers, it seems this year's trend line is still relatively high compared to the post-2010 years, which makes sense, as CT SIA is relatively low right now (and volume relatively high, which means thickness goes up too):
The Polar Science Center's thickness graph shows the trend line dashing off on its own though, with 2015 now hovering between the top droppers and the rest:
This year's melting season has basically wiped out the 2014 rebound (or 'recovery' as some people try to sell it), but it's still very much up in the air whether the 2015 trend line will dip below that of 2013 as well. 2013 didn't drop all that much during August, the least in the 2006-2015 period, which is only 372 km3 below the average.
The thing is that the weather has switched again, and a weak cyclone is dominating that part of the Arctic where most of the thick ice is situated. There's some discussion on the forum whether this is good for melting or not. My experience is that area/extent decrease tends to stall when cyclones dominate, especially if these cyclones aren't all that strong, and things simply don't move. At this point compaction and transport become more important for how low the melting season ends up.
But there is some transport going on because of the weak cyclone, and it's in the Beaufort and Chukchi Seas, where most of the thicker multi-year ice is. These floes are pushed towards the Canadian/Alaskan coast where anomalously warm water is finishing them off. Of course, I'll have more on this in the ASI update, but it'll be interesting to see what this will do to volume.
And so we wait and see whether the 'recovery' gets wiped out (something I alluded to in this guest blog for the Guardian Environment page).
In 2013 a low pressure area formed over a dome of cold fresh water that had built up under the very high pressure of the previous winter. The cold water and sea ice spread under that low, melting stopped and temperatures dropped.
This year low pressure in winter months flushed cold fresh water out of the Arctic towards the Labrador sea. In July, the water in the Beaufort sea and the Canadian Arctic was warmed by fair skies and warm temperatures. The lows this year are already mixing up that warm water with the ice and melting it.
This year is on track for thickness to cross 2013 levels in mid September. This time of year melting momentum is in actuality the amount heat content of the sea water below the ice.
-FishOutofWater
Posted by: D | August 04, 2015 at 20:01
Just adding my two cents about cyclones and sea ice concentration. Work done by Lammert et al. 2009 Observation of cyclone-induced inertial sea-ice oscillation in Fram Strait showed that cyclones had to have a certain size and speed to resonantly force sea ice to move inertially, or in other words inject mechanical energy into the ice pack. I showed in my MS thesis (submitting to GRL soon!) that strong cyclones that resonantly forced sea ice near-inertial motion typically caused convergence of the ice pack. I also found two high pressure systems which resonantly forced the ice pack, but instead of convergence I saw a weak divergence. Zhang et al. 2000 Recent Changes in Arctic Sea Ice: The Interplay between Ice Dynamics and Thermodynamics showed that dynamics can play a role in in an ice-albedo feedback where a diverging ice pack injects thermal energy into the upper ocean and enhances melt. I guess what I'm trying to get at is that a weak cyclone is will cause less convergence (compared with a stronger cyclone) and less compaction so there's slightly more open water to transfer heat from the atmosphere into the ocean. But this process is less efficient than say a high pressure system or lateral advection. I need some time to pull up the numbers, but I'd be really interested in seeing how wide and how fast this cyclone is moving in Beaufort/Chukchi.
Posted by: Chase Stoudt | August 04, 2015 at 20:25
Thanks, Chase. Very interesting.
If I understand correctly the current cyclone is too weak to let sea ice converge, which is why those MYI floes are being pushed towards the coast, ie their doom.
And how about GAC-2012?
Posted by: Neven | August 04, 2015 at 21:05
Neven, CT anomaly rose from -1.58 to -1.64 in the last day. I didn't track the area number but it's down to 4.126m.
Did I read you correctly earlier saying that CT lags by 3 days? If so we're in for some very interesting drops in the next few days.
If things continue as they are, 2013 volume is going to be beaten before September. But, of course, it depends on the cyclone in the Beaufort.
Although I'm much more interested in the melting and opening of the pack up towards 85N. I didn't see that coming from that direction. The Laptev is slow and stable but the Beaufort is liteally disintegrating.
I wake up every morning, look at the Bremen map and think "how did that happen?".
Posted by: NeilT | August 04, 2015 at 21:23
Not really. After 4.126 come drops of +10K and -52K.
Yes, the sight is becoming more spectacular by the day, especially those holes. This melting season has a whole personality of its own.
Posted by: Neven | August 04, 2015 at 21:38
Chase, it is plausible then that a weak persistent cyclone (such as the PAC of 2013 or the current low near the Beaufort sea) might break and disperse ice as much as, or more than, a very strong but short-lived cyclone (such as the GAC of 2012)
Posted by: navegante | August 04, 2015 at 21:43
Ya I just pulled up the ECMWF for that system in the Beaufort. My eyeballed values are about 1115 km wide and moving at ~10 meters a second, so really slow and big. Using the Lammert metric the Diameter/ground track speed equals ~31 hours. 3/4 of the local near-inertial period at this latitude is 9.3 hours so it's not even close to make the ice respond inertially, it's all going to be advection like you said with very little to no convergence. I'm not a modeler so I can't speak about Zhang's model results but I agree the 2012 cyclone was definitely powerful enough to make the ice move inertially, thus mixing the upper water column (I could go on here about pumping the pycnocline and what kind of internal waves could have been generated but I won't). That being said, with this current system in the Beaufort you still have broad scale oceanic convergence which can act to deepen the pycnocline and advect warmer water, although I don't know what the extent or magnitude that would transfer through the ice pack.
Posted by: Chase Stoudt | August 04, 2015 at 22:08
DMI model volume is tracking 2011 now, well below 2013 levels.
http://ocean.dmi.dk/arctic/icethickness/images/FullSize_CICE_combine_thick_SM_EN_20150803.png
Based on observations of NASA worldview, I'm inclined to think the DMI values are closer to reality, but what's reality?
-Fish aka George
Posted by: D | August 04, 2015 at 22:20
Navegante said: "...a very strong but short-lived cyclone (such as the GAC of 2012)."
My understanding is that GAC 2012 was actually remarkably long-lived. Simmonds & Rudeva ("The Great Arctic cyclone of 2012" in GRL, 2012) stated that the nearly 13-day duration of GAC 2012 was "very atypical of Arctic storms, particularly in August." They conclude: "Using our multiple-index approach (based on cyclone properties and longevity) we conclude that AS12 was the most extreme August Arctic cyclone (out of a population of 1618). When all Arctic cyclones were considered (which included the more vigorous winter systems) AS12 ranked in position 13 out of a compilation of 19625 storms."
Posted by: Jenny E. Ross | August 04, 2015 at 23:14
BTW, Chase, there has been some confusion lately on the Arctic Sea Ice Forum regarding Ekman and cyclones and di/convergence. It resulted in this topic with folks trying to get to grips with the issues (I just wait until they agree and then act as if I knew it all the time). Maybe you could share some of your knowledge there.
Posted by: Neven | August 04, 2015 at 23:55
My last post was in response to Neven.
Posted by: Chase Stoudt | August 04, 2015 at 23:56
You are quite correct, Jenny, the GAC was very long lived. In this situation, the Eckman pumping has already been done along the Canadian and Alaskan coastlines by July's persistent Beaufort high. This weak storm will blow ice over July's warm waters.
Posted by: D | August 05, 2015 at 00:46
George asked:
Well, we are anyway entitled to compare with the DMI-charts from 4 months ago. And to compare leads fatally to these conclusions:
- Only a small area of 5 m thick ice remains - the zone between Station Nord [Princess Ingeborg Peninsula] and Peary Land.
- About 70 % of the 4 meter thick ice has vanished away.
- All of Cincinattus' precious 6 m thick ice in the Beaufort and Chukchy Seas has disappeared too.
And it ain't finished yet ...
Posted by: Kris | August 05, 2015 at 01:58
The deniers have failed compared to all the thickness models. PIOMAS, however, seems to be lower in 2013 than other models. The very cold late spring in 2013 had surprisingly little effect on the PIOMAS thickness. I'm not convinced that PIOMAS is better than other models.
Navy HYCOM still appears to have artifacts of the change in the grid at 80°N so I only use it for comparisons and trends. I don't trust thickness models because they haven't demonstrated consistency.
Posted by: D | August 05, 2015 at 03:48
Noticeable change in the Arctic Death Spiral, as Jun-Jul* 2015 jumps from 6th to 5th record lowest.
Latest: http://haveland.com/share/arctic-death-spiral.jpg
(permanent filename: arctic-death-spiral-1979-201507.jpg)
* I use July because it is the latest series, whereas Neven uses August when it is published - both valid of course.
Posted by: Andy Lee Robinson | August 05, 2015 at 04:46
In response to a comment by NeilT regarding the trajectory of the CT area figures over the next few days, Neven wrote...
"Not really. After 4.126 [Day 214] come drops of +10K and -52K"
That should then put the CT area at 4.084 million sq kms (ignoring any rounding) as at Day 216. By way of comparison, the lowest recorded area in the CT database prior to 2007 was just 4.017. This occurred on Day 266 of 2006. (Hmmm, there are three 6s in there!)
On the flip side, as mentioned a few days ago on another thread, starting on Day 215 last year, the CT numbers virtually flat-lined for 15 days, losing just 150K over this period. Watch this space.
Moving on...
Kris wrote "... All of Cincinattus' precious 6 m thick ice in the Beaufort and Chukchi Seas has disappeared too"
Still, he was right about the ice not retreating polewards of Wrangel Island.
Oh! Wait a minute...
Posted by: Bill Fothergill | August 05, 2015 at 11:45
Thank you Jenny, I didn't know that:
My understanding is that GAC 2012 was actually remarkably long-lived. Simmonds & Rudeva ("The Great Arctic cyclone of 2012" in GRL, 2012) stated that the nearly 13-day duration of GAC 2012 was "very atypical of Arctic storms, particularly in August. <\i>
Posted by: navegante | August 05, 2015 at 14:29
Well, as we set up for the 'finale' of the ice-melt season, it doesn't look like a record. But it also sure doesn't look like 'recovery' either.
And with the global mean and ENSO being what they are, I've got to wonder about the freeze season coming. Will we see 'pre-pre-conditioning' for the 2016 season?
Posted by: Kevin McKinney | August 05, 2015 at 19:07
Cincinattus, I'd forgotten that uncouth jerk.
What did Cincinattus say?
[QUOTE]
"What I think will happen, as I said before, is that this year's melt will proceed to Wrangel Island and then stop. And there will be weeping and wailing and gnashing of teeth in this blog, but the ice will not melt north of Wrangel. And come September (if you haven't banned me) I will come in here and jeer jeer jeer at you poor poor alarmists, let down by Gaia yet again, oh why, oh why, Et tu Gaia?!? (remember that?)"
[/QUOTE]
http://neven1.typepad.com/blog/2015/05/20142015-winter-analysis.html?cid=6a0133f03a1e37970b01bb082c3a60970d#comment-6a0133f03a1e37970b01bb082c3a60970d
Normally when someone makes a reasoned prediction that is shown wrong by events I don't let it cloud my assessment of anything else they say, we can all get it wrong. But when someone makes an unreasoned prediction and in doing so behaves with such bad grace, and bad manners...
Posted by: Chris Reynolds | August 05, 2015 at 21:59
Oh yes, and the 6m crap was delivered with equally bad grace...
http://neven1.typepad.com/blog/2015/03/the-ns-are-calling-the-maximum.html?cid=6a0133f03a1e37970b01b7c7709e8b970b#comment-6a0133f03a1e37970b01b7c7709e8b970b
Posted by: Chris Reynolds | August 05, 2015 at 22:01
Too bad I banned him. ;-)
Although if I hadn't, he'd probably be whining about how there's a ship stuck in the ice somewhere in Baffin Bay.
Posted by: Neven | August 05, 2015 at 22:02
Unfortunately he wouldn't be on it either....
Posted by: NeilT | August 05, 2015 at 22:42
Would really like a like button!
Posted by: Andy Lee Robinson | August 05, 2015 at 23:37
can you set up a like button on this blog Neven? there are times when a like would be appropriate response to a comment.
Posted by: philiponfire | August 06, 2015 at 06:12
Neven,
Please avoid the "Like"-button. This is not a vote forum or a beauty contest. It is a deadly serious matter for the whole world. Having Cincinattus around for a short while was thought-provoking, which is good in my mind.
Please avoid the scape-goat'ism, which has been sticking out it's grim face in this thread for a while. It is really bad taste to continue ridiculing a guy, whos has been "banned for life" on this site.
Posted by: P-maker | August 06, 2015 at 10:59
P-maker, thanks for your concern. Even if I would want it, I don't think it's possible to install a like-system.
Posted by: Neven | August 06, 2015 at 11:06
At the risk of going off topic.
P-maker. I'm on record for stating the obvious here. 2 Billion lives forfeit. I don't know how to make it any more "serious" than that.
As a person who makes their living in IT and also set's up forums and, from time to time, provides admin services to forums, I find one thing constant.
If you want a life ban you have to work at it. In the case of this site it will be making ludicrous statements with no basis in fact, dismissing both evidence and very in depth scientific research with flippant remarks and generally making such a nuisance of yourself that you wind up standing on the outside shouting at yourself. Or go back to a place like WUWT and howl at the moon along with the other like minds.
Whilst whacking this particular mole might be thought provoking, I've found, over the last 19 years of watching, discussing and contributing, that after about the first 500 times it just becomes boring drudge work.
Neven, It is possible and a quick search elicits an article
http://hofmannsven.com/2013/laboratory/wordpress-post-like-system/
Which will do that. However, I must admit, that what the author calls I prefer to keep things simple does not fall into my lexicon of simple. Personally I'd go for the plugin every time unless it was unstable...
Posted by: NeilT | August 06, 2015 at 17:13
Gah, ignore that last bit. Typepad not wordpress. Must be a slow day and my brain has not caught up.
Posted by: NeilT | August 06, 2015 at 17:15
Yes, avoiding a 'like'-athon would be a very good idea.
I was looking at the Arctic sea ice extent graphs, again, and it looks like the problem only really becomes solid after 2005.
Do the volume statistics reflect the year 2005 as being some type of significant year?
Posted by: AbbottisGone | August 06, 2015 at 22:59
Also, being ever so slightly conservative, it seems volume essentially reaches minima at the start of August.
Is it fair enough to make this sort of statement?
Posted by: AbbottisGone | August 06, 2015 at 23:06
I don't know about the volume stats for 2005 but it was a real shock year. That was the year the ice retreated so far they discovered a new island....
It led to huge expectations in 2006. 2006 started very low in area and continued low until it suddenly stalled for a long time. Dashing at the end to not quite make it.
This preconditioned 2007.
As I recall it, most of it started in 2005. Although there was a lot in the press about a UK size chunk of ice which suddenly vanished in the Beaufort (or thereabouts), in October or November. Can't remember if it was 2004 or 2003 but it was before 2005. I think it was 2004 as I was in Sweden then and I recall printing out the Bremen maps at the time.
Sorry I can't be more precise but I've searched for all the news articles on the late autumn loss since and can't find them.
Posted by: NeilT | August 06, 2015 at 23:29
Like is quite useful although it gets abused. The alternative is loads of posts with +1 which gets messy real quick.
I do understand the sentiment though, one of the reasons I no longer have a FB account is I couldn't find the "Acquaintance" button....
Posted by: NeilT | August 06, 2015 at 23:33
Cheers: enlightening!
The fourth graphic down, if I squint my eyes, possibly reveals a slow then fast crash toward a new normal after 2005. I'm obviously trying to confirm my bias here though...
Then of course 2014 represents a very robust challenge to the new status quo in the name of 'a recovery' with 2015 worth all the popcorn in the world in my opinion.
Just call me keenly interested ~;^>'///,<
Posted by: AbbottisGone | August 06, 2015 at 23:48
Saying all that I am so glad for the 2014 recovery that gives us our current 2015... because if it wasn't there I think mass panic would be a reality...
We need to wake up NOW I feel!
Posted by: AbbottisGone | August 07, 2015 at 01:20
Record-breaking polar bear spurs climate change concerns
Thursday, August 6, 2015, 11:59 AM - A hungry and skinny polar bear in Norway is raising concerns about climate change after it broke the record for the longest underwater dive with a remarkable time of three minutes and 10 seconds.
The bear smashed a previous record of 72 seconds. It swam 45 to 50 metres without coming up for air in an effort to stalk three bearded seals. The event was recently published in the journal Polar Biology, highlighting the desperate measures polar bears must take to survive and the link between climate change and melting sea ice.
These pictures will make you sick
Posted by: Colorado Bob | August 07, 2015 at 02:40
http://i1377.photobucket.com/albums/ah68/csantamaria/polarbear-0608_zpsnmbqnhlo.jpg
Posted by: Colorado Bob | August 07, 2015 at 04:30
The new face of climate change
Credit :
Arctic guide Rinie van Meurs.
Posted by: Colorado Bob | August 07, 2015 at 04:31
That is one hungry looking polar bear!
Posted by: philiponfire | August 07, 2015 at 08:12
To be thorough, or in other words not to double handle the situation: can we get some info on the correct and fit/healthy state of a polar bear?
Of course it looked not right to me on first inspection but do they periodically lose and then gain weight? I'm sorry if I'm being ignorant it just seems an important point..
Posted by: AbbottisGone | August 07, 2015 at 09:11
It is normal for polar bears to lose weight around the time of the Sea Ice minimum, as their availability of food follows an annual cycle. They have evolved as ambush predators, and two of the most frequent ways they have of feeding would be...
a) Smashing through seal dens to take their young, and
b) Hanging about at a breathing hole - waiting for an unsuspecting seal to pop up for what is likely to be its last ever breath.
Any form of hunting which involves serious amounts of chasing is very inefficient from an energy budget perspective.
Seals tend to have their young in the spring, so that time of year should normally represent a bit of a food bonanza for the bears, during which they would expect to pile on the pounds - in anticipation for the forthcoming months of famine. However, early ice break up is bad news for both bears and seals alike.
http://cmsdata.iucn.org/downloads/fact_sheet_red_list_ringed_seal.pdf
It is very important to be able to do live capture on seriously underweight bears in order to determine the cause. Obviously, the head-in-the-sand brigade will claim that any patently underweight bear just happens to be either: old, or sick through natural causes, or sick through some pathogen ingestion.
This later point (eg pathogens such as PCBs) can be very prevalent in what are known as apex predators. These are creatures at the top of their food chain who have no significant natural predator (ie Trophic Level 5) within their particular biome.
However, the species of hairless ape with the high powered telescopic rifle and the penchant for pollution has seriously dented the claim of Ursus maritimus to be at Trophic Level 5.
Limited amounts of crap (such as PCBs) get ingested by phytoplankton and zooplankton. These get gobbled up by small fish, which are themselves eaten by larger ones. Seals prey on these fish, and the pollutant can consequently increase in concentration at each stage, eventually reaching seriously harmful levels as one goes up through trophic levels.
http://www.polarbearsinternational.org/about-polar-bears/essentials/pollution
For info on the 19 designated sub-populations of polar bears as at 2014, see...
http://pbsg.npolar.no/en/status/status-table.html
For a possibly more meaningful description about the 4 physically distinct sea ice environments (convergent, divergent, seasonal and archipelago) it is worth looking at...
http://www.polarbearsinternational.org/where-do-polar-bears-live/polar-bears-sea-ice-regions
This is probably old news to many on this site, but, way back in 1973, it was finally realised that action had to be taken to address the "over harvesting" (not my words, I assure you) of polar bears. The result was the Oslo agreement between the 5 polar bear nations. (USA, Canada, Norway, Russia {the USSR, as it was then} and Denmark/Greenland)
Since then, polar bear numbers did indeed make a very marked recovery, but loss of habitat is already beginning to undo this recovery. Polar bears are listed in Appendix II of the Convention on International Trade in Endangered Species of Wild Fauna and Flora, or CITES. To quote the relevant text...
"Appendix II includes species not necessarily threatened with extinction, but in which trade must be controlled in order to avoid utilization incompatible with their survival."
http://pbsg.npolar.no/en/agreements/CITES.html
I hope at least some of the above was informative.
cheers btf
Posted by: Bill Fothergill | August 07, 2015 at 11:02
Being a time for informative debate, cheers mate!
Lastly, was the bear in question 'sickly' ?
Posted by: AbbottisGone | August 07, 2015 at 16:05
In the ongoing debate about the accuracy of various metrics, NSIDC have just posted an absolute cracker.
According to the daily extent figures, the Arctic has just gained almost 1.7 million sq kms overnight - ie between the 5th and 6th August.
ftp://sidads.colorado.edu/DATASETS/NOAA/G02135/north/daily/data/NH_seaice_extent_nrt.csv
The book is now open on...
a) how long until it gets fixed
b) what the revised value will be
c) how long until some moron starts trumpeting about "the recovery" or "data manipulation"
I have informed the NSIDC, so I expect this will be corrected in the very near future.
@AiG - Sorry, I have no info about the specific bear.
Posted by: Bill Fothergill | August 07, 2015 at 16:16
RE: Explosive growth of Arctic Sea Ice
The dodgy figure mentioned above has just been incorporated into the running 5-day average displayed on NSIDC's Charctic Tool. As there is a delay (perhaps 15 minutes or so) before incorporation into Charctic, I thought it might have got picked up at that stage.
As it is the only "sharp" point of inflection, that should set off warning bells to anyone with an ounce of common sense. However, that still excludes a significant portion of the population.
Posted by: Bill Fothergill | August 07, 2015 at 16:22
Re: Explosive growth
If you look at the map, it all comes pretty clear what happened. That obviously can't be right.
Posted by: Scott | August 07, 2015 at 17:47
The NSIDC were, as usual, very prompt to respond to my email.
"Hi Bill,
Thank you for contacting NSIDC. On August 5, a problem arose with the F17 DMSP satellite that provides data to generate the daily maps and time series in the NSIDC Sea Ice Index and Arctic Sea Ice News and Analysis as well as the Greenland Today daily melt extent. This has led to spurious values of sea ice for both the Arctic and Antarctic, and unreliable melt data for Greenland for this date. NSIDC is in the process of removing the spurious data, and will be closely monitoring the incoming F17 data stream.
Let me know if you have further questions.
Regards,
Kara"
Posted by: Bill Fothergill | August 07, 2015 at 19:08
Wow, they even hire people who are named after one of the Arctic regions.
Posted by: Neven | August 07, 2015 at 19:13
Nice one, Neven.
I've just checked my email history, and the first communication I had with Kara was almost 4 years ago. In all that time I never made the now-obvious connection.
Perhaps the next time you exchange pleasantries with Mark Serreze, you can enquire if this is policy?
Posted by: Bill Fothergill | August 07, 2015 at 19:31
"According to the daily extent figures, the Arctic has just gained almost 1.7 million sq kms overnight - ie between the 5th and 6th August."
Bill, isn't this possible though due to the ice in the Beaufort disbursing to a wider perimeter (extent), but not take into account the now open water pockets that occurring proportionately? Once that entire area melts out we should get a big drop in extent.
I suppose it comes down to how extent is defined.
Posted by: Hans Gunnstaddar | August 08, 2015 at 04:05
Not possible. The maps also looked crazy; the Antarctic one was almost psychedelic. The graphs are now fixed but the maps still have problems--big gray wedges.
Posted by: Philip Cohen | August 08, 2015 at 06:07
..meaning the graphs are accurate?
Posted by: AbbottisGone | August 08, 2015 at 09:18
Hans & Philip & anyone else not realizing I was speaking in jest...
Although my wife would undoubtedly disagree with the following assertion, I am not that dumb as to believe that there was a +1.7 million upward hike in Arctic sea ice extent. If you read the rest of the sequence, I think it's clear that I was trying to inject some humour.
However, to spell it out explicitly, the email sequence between myself and the NSIDC went like this...
1) Me to NSIDC...
"Hi there,
As an avid "watcher" of developments in the Arctic, I eagerly await your daily updated figures for Arctic Sea Ice.
The value for the 6th of August has just been added to...
ftp://sidads.colorado.edu/DATASETS/NOAA/G02135/north/daily/data/NH_seaice_extent_nrt.csv
This value is clearly in error, as even the most blinkered of climate change deniers would not be prepared to accept that the extent has gone up by almost 1.7 million square kilometres overnight at any time of year - let alone in early August.
I eagerly await learning the revised value.
Best wishes Bill Fothergill"
2) NSIDC to me (NB This was reposted here yesterday evening - see above)...
"Hi Bill,
Thank you for contacting NSIDC. On August 5, a problem arose with the F17 DMSP satellite that provides data to generate the daily maps and time series in the NSIDC Sea Ice Index and Arctic Sea Ice News and Analysis as well as the Greenland Today daily melt extent. This has led to spurious values of sea ice for both the Arctic and Antarctic, and unreliable melt data for Greenland for this date. NSIDC is in the process of removing the spurious data, and will be closely monitoring the incoming F17 data stream.
Let me know if you have further questions.
Regards,
Kara"
3) Me to NSIDC...
"Hi Kara,
Thank you for the usual very prompt response.
The daily images for both the Arctic and Antarctic left little doubt that the satellite was generating spurious values.
Actually, the heavily pixelated swathes across both images looked quite pretty - mad, but pretty nonetheless.
Best wishes Bill F"
4) Me to NSIDC...
"Hi again Kara (or whoever picks up this email)
I see that the data file at ...
ftp://sidads.colorado.edu/DATASETS/NOAA/G02135/north/daily/data/NH_seaice_extent_nrt.csv
has been amended, and now shows a physically realistic decrement of -124 thousand sq kilometres between the 5th - 6th August, as opposed to the obviously ludicrous +1.7 million kms growth shown earlier.
This could simply be my misinterpretation, but there still seems to be a significant mismatch between the csv data file and the corresponding daily image. The csv is showing that there is a section of data missing which equates to 119 thousand sq kms. However, the daily image is showing a greyed-out sector lying roughly between longitudes 120 degrees East and 15 degrees East. At the latitudes involved - about 70N, and further poleward - this area would be in the order of 3 million sq kms, not 119 thousand.
As I said, this could just be me misinterpreting the way you are presenting the data. For example, it could be that there is a 119k data drop that is smeared over the much larger greyed out area.
Best wishes Bill F"
5) NSIDC to me...
"Hi Bill,
The grey area in the image is missing data. I suspect the current value in the .csv is off and only calculating the data available. In the time series chart we account for the missing data by averaging the extent for that region from the day before and the day after the gap, a mathematical technique called interpolation. Interpolation is an appropriate approach because ice cover changes slowly. It will get trickier if the sensor continues to have problems, but we will have to wait and see. Also, note that we are closed on the weekend. We might suspend processing of new data over the weekend, or may let it run, our science staff will make that call. But don't be alarmed if you continue to see artifacts or no new data. We will do our best to keep our readers apprised with notices on the page.
Regards,
Kara"
I hope that clears things up somewhat.
cheers: bill the frog
Posted by: Bill Fothergill | August 08, 2015 at 09:30
Cool man, cheers!
Posted by: AbbottisGone | August 08, 2015 at 10:13
May I ask, in order to catch up on events:
..the thing about 2012 and 2007 is that their 'pre-conditioning' started in June?
Posted by: AbbottisGone | August 08, 2015 at 17:36
AbbottisGone, yes, the ice pack in 2007 and 2012 saw much more preconditioning than 2015 during May and June (see the analyses I wrote). 2007 had perfect conditions for extent decrease almost the entire melting season, with a persistent dipole causing lots of transport through Fram (and Nares) Strait, lots of compaction towards the end of the melting season, and lots of open skies and warm temps on the Pacific side of the Arctic.
2012 was not entirely like 2007, but had even warmer temps and then the GAC in August.
Posted by: Neven | August 08, 2015 at 20:06
2007 also saw Nares Strait exporting ice the entire winter (2006-7 - only time 'ever'). Although typically about 10% of what is exported through Fram Strait, this extra Nares Strait ice export had to help with the 2007 September minimum.
Posted by: Tor Bejnar | August 08, 2015 at 21:09
Some scientists from the Russian "North Pole 2015" ice camp:
caught on a webcam:
shortly before being evacuated by the icebreaker "Kapitan Dranitsyn"
http://barentsobserver.com/en/arctic/2015/08/russian-arctic-scientists-be-evacuated-ice-floe-05-08
Posted by: Jim Hunt | August 09, 2015 at 12:36
Nice photos Jim,
It looks like this drift station came equipped with self-digging latrines.
Jim, is this anything to do with Camp Barneo, or is that a totally separate thing? (I get confused easily.) I've also lost track of the numbering, is this NP41? (Although, since it's Russian, that should be SP41.)
Anyone unfamiliar with the background to these Russian Drift stations could start by looking at...
a) the Woods Hole Beaufort Gyre Project
http://www.whoi.edu/page.do?pid=66677
b) the extensive background material available from NSIDC
https://nsidc.org/cryosphere/arctic-meteorology/studying.html
c) something called the "Arctic Sea Ice Blog", whatever that is
http://neven1.typepad.com/blog/2013/05/russia-abandoning-ice-station.html
Posted by: Bill Fothergill | August 09, 2015 at 13:29
Thanks Bill,
This year's SP-41 (following the old naming convention) was indeed an offshoot of Camp Barneo. Lots more information and photos over on the forum at:
http://forum.arctic-sea-ice.net/index.php/topic,1189
Posted by: Jim Hunt | August 09, 2015 at 16:07
Bill Fothergill
Thanks for the comments on the bears.
As for the bear being "sick", it's a pretty slick trick to hold one's breath for over 3 minutes when your "sick".
Anyway we slice it The entire system is under going tremendous change.
Iceland: Volcanic eruptions could be a consequence of melting glaciers
The research, which looked at the glacial melting occurring in the North Atlantic island as a result of climate change, showed that the country’s glaciers are losing around 11 billion tonnes of ice each year.................. The study – Climate driven vertical acceleration of Icelandic crust measured by CGPS geodesy – was carried out by researchers from the University of Iceland and the University of Arizona. The group studied data from 62 GPS sensors around Iceland to work out how the earth responded to climate change-driven glacial melting; they found that the country is actually rising by as much as 35 millimetres a year.
Read more: http://www.icenews.is/2015/08/08/iceland-volcanic-eruptions-could-be-a-consequence-of-melting-glaciers/#ixzz3iKloGWHv
Posted by: Colorado Bob | August 09, 2015 at 18:01
Warning to all fake skeptics, especially to those who read them at WUWT, here was example of vast non knowledge presented, in terms of their great skills in assessing sea ice:
>>>>>Neven, are you the Warden, or just the head inmate?
[Snipped some of the exaggerations/insults, but yes, I'm the head inmate, and you're the paragon of rational thought; N.]
In any event, the inmates here will be sadly disappointed when this year's melt reaches Wrangel Island, north of which the ice is 6 meters thick. Sorry guys, that will be all she wrote.
[Of course, I'll let this one stand too, for future reference; N. :-) ]
Posted by: Cincinnatus | April 02, 2015 at 03:34<<<<<<<<<<
Look at poor Cincinnatus Bombed out prediction 40 days before Minima:
http://arctic.atmos.uiuc.edu/cryosphere/NEWIMAGES/arctic.seaice.color.000.png
outch!!!
I warned him, but alas no recant, no reasoning, just bland "gut " politically motivated "feelings" jutting all over the place. I must remind that reality is blunt and unrelenting, but predictable if your feet are anchored in the practice of science…….
And then I wrote Baffin Bay sea ice will melt much slower, but geeeeez , its been awesomely slow, 2015 has its own style. Much predictable by a rather spectacularly stable winter pattern.
Posted by: wayne | August 09, 2015 at 22:06
Wow, they even hire people who are named after one of the Arctic regions. - Neven
Ha! Clearly a case of nominative determinism. Kara had no choice but to be in role related to the Arctic. See https://www.newscientist.com/article/mg22530101-100-feedback-nominative-determinism-redux/
Posted by: Jon Hurn | August 10, 2015 at 04:47
After such an excellent explanation I am surprised Bill didn't respond
"I see Kara" or perhaps "Kara I see" but perhaps she gets that all the time.
Posted by: DavidR | August 10, 2015 at 08:28
@ Colorado Bob
"As for the bear being "sick", it's a pretty slick trick to hold one's breath for over 3 minutes when your "sick"."
Continue the logic Bob. It would also seem that it should be pretty hard for a bear suffering severe malnutrition to swim underwater in search of prey for over 3 minutes.
The previously observed record time of ~ 72 seconds was clearly non-representative of the capabilities of these animals. However, the point I was trying to make is one that Jim Hunt has repeatedly raised, both here and over at the Great White Con; namely that it is vital to accurately portray the context in which some "factoid" exists.
@DavidR & Neven
"...I am surprised Bill didn't respond
"I see Kara" or perhaps "Kara I see" ..."
I suppose I'm going to get snowed under with remarks like that.
;-)
Posted by: Bill Fothergill | August 10, 2015 at 10:41
An example of the "out of context" experience:
Looking at the Cryosphere Today daily figures for Antarctic Sea Ice Area, one sees the following...
Year 2015, Day 218, 14.189 million sq kms
Year 1984, Day 218, 14.717 million sq kms
Conclusion: Antarctic Sea Ice is therefore retreating.
Now, the above figures are "accurate" - well, they are as contained in the CT database - the accuracy is a function of the measuring equipment and analysis algorithms. However, the "conclusion" is the type of total bollox that results from world-class cherry-picking of data.
If one were to look at the relevant CT chart, but with only 2015 and 1984 displayed, this begins to set the figure in an appropriate context. It is immediately clear that, for most of the year thus far, the ice area in 2015 greatly exceeded that observed in 1984.
(And before Neven or DavidR can say anything - yes, I did notice it was "1984".)
Posted by: Bill Fothergill | August 10, 2015 at 11:06
Will there be any sudden large changes to extent if/when the leading edge of the ice pack in the Beaufort Sea melts back to the large holes further north?
Posted by: Jon Hurn | August 11, 2015 at 06:41
Jon - There have already been some "sudden large changes to extent":
According to JAXA (or NIPR or ADS or whatever you call it these days) there have been several "almost 100k" drops in a row.
Posted by: Jim Hunt | August 11, 2015 at 18:11
I have to wonder what the Danish are using to come up with their volume numbers:
http://ocean.dmi.dk/arctic/icethickness/images/FullSize_CICE_combine_thick_SM_EN_20150811.png
Note that 2014's volume continued to drop well into September:
http://ocean.dmi.dk/arctic/icethickness/images/FullSize_CICE_combine_thick_SM_EN_20140910.png
Posted by: TenneyNaumer | August 13, 2015 at 05:16
@ TenneyNaumer,
Isn't that map indeed intimating 6 m thick sea-ice does exist in the Arctic?
Posted by: AbbottisGone | August 13, 2015 at 07:52
Tenney,
That question was addressed on the forum:
http://forum.arctic-sea-ice.net/index.php/topic,1112.msg55199.html#msg55199
Our operational model system consists of the HYCOM version 2.2.55 and CICE version 4.0 models, coupled using the ESMF coupler. The model resolution is about 10 km, and the domain covers the Arctic Ocean and the Atlantic Ocean to approximately 20°S. We currently use ECMWF operational atmospheric forcing, and the model assimilates OSISAF reanalysed sea ice concentration and GHRSST Level 4 DMI_OI sea surface temperatures.
Posted by: Jim Hunt | August 13, 2015 at 09:32
Meant to repeat this which I've said in previous years. I like to swim in the North Atlantic (not particularly north, Boston US "North Shore"; it took me a while to figure this out and take advantage of it) and it is warmer in early September than it is most of July. But the earth's curve will likely make that different further north.
Posted by: Susan Anderson | August 14, 2015 at 05:53