I always find it interesting as to why some stories get traction in the mainstream media and why some don’t. In online science discussions, the fate of this years summer sea ice has been the focus of a significant betting pool, a test of expert prediction skills, and a week-by-week (almost) running commentary. However, none of these efforts made it on to the Today program. Instead, a rather casual article in the Independent showed the latest thickness data and that quoted Mark Serreze as saying that the area around the North Pole had 50/50 odds of being completely ice free this summer, has taken off across the media.
The headline on the piece “Exclusive: no ice at the North Pole” got the implied tense wrong, and I’m not sure that you can talk about a forecast as evidence (second heading), but still, the basis of the story is sound (Update: the headline was subsequently changed to the more accurate “Scientists warn that there may be no ice at North Pole this summer”). The key issue is that since last year’s dramatic summer ice anomaly, the winter ice that formed in that newly opened water is relatively thin (around 1 meter), compared to multi-year ice (3 meters or so). This new ice formed quite close to the Pole, and with the prevailing winds and currents (which push ice from Siberia towards Greenland) is now over the Pole itself. Given that only 30% of first year ice survives the summer, the chances that there will be significant open water at the pole itself is high.
The actuality will depend on the winds and the vagaries of Arctic weather – but it certainly bears watching. Ironically, you will be able to see what happens only if it doesn’t happen (from these web cams near the North Pole station).
This is very different from the notoriously over-excited story in the New York Times back in August 2000. In that case, the report was of the presence of some open water at the pole – which as the correction stated, is not that uncommon as ice floes and leads interact. What is being discussed here is large expanses of almost completely ice-free water. That would indeed be unprecedented since we’ve been tracking it.
So why do stories about an geographically special, but climatically unimportant, single point traditionally associated with a christianized pagan gift-giving festival garner more attention than long term statistics concerning ill-defined regions of the planet where very few people live?
I don’t really need to answer that, do I?
Somewhat off topic, but the general subject is melting ice.
After a visit to the local museum, my kids asked, “Why did all the ice melt from the last ice age?” and “How fast did it melt?” The “most recent” means the most recent North American glacial interval, Wisconsin, which I think ran 70,000 to 10,000 years ago. My best internet digging around says the ice was retreating at the rate of 0.3-1 km/year for about 3000 years, which sounds awfully fast, and then it sort of stabilized into the present era. So a lot of heat was somehow quickly available to melt the ice.
For a cause, it sounds too fast and abrupt to be accounted for by the normal astronomical causes (Milankovich cycles). The “present best guess” that I can discern is that the ocean currents reorganized themselves to bring more heat from the tropics. Reasonable, but is there any theory as to why the currents rearranged themselves? Can someone point me to a recent HS or college intro level publication on the topic?
Thanks in advance.
Thanks, Nick, I was getting the images via a different link.
Found that: http://psc.apl.washington.edu/northpole/
NPEO 2008 Ice Mass Buoy 30065
latest atmospheric data co-located with WebCams
08/08/2355Z 83.386°N 2.667°E -0.4°C 1006.1mb
This one:
http://www.crrel.usace.army.mil/sid/IMB/2008E.htm
Let me just interject one thing here, going back to April. At that time, the skies above the Arctic were very clear, and so it was possible to get really good views, updated about every two hours or so, from the Canadian weather service site:
http://www.weatheroffice.gc.ca/data/satellite/hrpt_dfo_ir_100.jpg
(Put that link in your favorites/bookmarks for next spring.)
Remember, there was very little multi-year ice and it was mostly hanging around north of Greenland and the Canadian Archipelago.
Anyway, some time toward the end of April, if I remember correctly (always a question), cracks appeared all over that thin ice, over the entirety of it. Of course, I was not observing “cracks” — what was observable on the IR satellite photos was the vapor coming from the cracks. Nearly the entire Arctic Sea appeared to have been crackle glazed, from Canada to Siberia.
As the days passed, the amount of vapor issuing from these cracks increased to the point that the wind could be seen to carry it off in trails. (It took me a while to figure out what was going on, being new to all this.)
Also, the crack along the entire outer edge of the Canadian Archipelago (now open water) appeared way back in early June.
As the thin ice in the middle of the Arctic Sea weakened further, the volume of vapor produced began to be quite dramatic. Eventually, so much water vapor poured out that it was no longer possible to get a good view of the ice.
Let me just say this — it was quite a show! But it is over until next spring.
If one of you gentlemen ever has the time, I could really use some help. The mechanics of heat exchange or whatever it is called are unknown to me. I don’t understand what is going on when the ice freezes or when it melts, and how that works in the Arctic. I just know that I saw a lot of vapor rising, which in my ignorance means that the water below the ice was warmer than the air above it. In my mind, an absolutely incredible amount of heat left the water (from April through June) and went into the air, and at some point, a type of equilibrium was reached after which very little vapor was created. If you ever have any time for explaining this, you can leave a comment on my blog, linked to my name above, unless you can leave it here. It would be greatly appreciated.
From today’s Observer [UK]:
First reference I’ve seen to a new Maslowski study… a fairly dramatic prediction.
[Response: It’s not a reference to a study – it’s more of an opinion… and one I’m unsure is widely shared. – gavin]
Gavin,
I have just linked to a recent Maslowski presentation (June 08) over at Gareth’s blog Hot Topic.
That Maslowski presentation (pdf) ishere (5.36 Mb pdf). The reason for Maslowski’s 2013 opinion seems to be:
page 16.
The graphs end in 2005, qualitatively the thinning since then seems to support a continuation of reduction, despite the levelling on that graph in 2003 to 2005. But I can’t get current figures to extend the graphs. i.e. The figures I have don’t allow me to reproduce the trend of the graph as shown, so it’s pointless trying to extend quantitatively.
I agree that Maslowski’s 2013 is not widely supported in the cryospheric science community, but I don’t find outright rejection. FWIW I use Maslowski’s 2013 as a lower bound, Stroeve’s 2030 as an upper (fingers crossed for the latter).
#751 Jerry,
All the references I have are complex. In short, the changes in incoming sunlight (at 65deg North) due to the Milankovitch cycles correlate well with the rate of change of the ice sheets. But it’s local processes that dominate at small timescales and in small areas, not the Milankovitch cycles themselves. Natural processes amplify the small changes in sunlight, a similar process is being seen in the Arctic where natural processes are amplifying the human impact.
If I find anything by next weeked I’ll post.
Wayne:
As of yesterday, too much cloud over the Archipelago for visual pics of the NWP. Much cloud over the central pack, but where there are breaks it’s a mess.
On the subject of clouds…
#753 Tenny Naumer,
I don’t think it’s quite over, I could still be wrong and this year might actually beat last year (a lot has happened since my post 725 on 1/8/08).
Water vapour from the ocean is a notable effect, and there was some awesome cracking in April. I’ll post answers to your questions at your blog within a few days.
Is Maslowski someone who could be invited here? I first stumbled over his students’ thesis work with Google searches a few years ago. I’ve wondered if the Navy postgraduate school thesis work is allowed to draw on data the Navy doesn’t release in detail — thinking that might explain both why their models seem to consistently differ from others, and why people including, you should pardon the expression, Wegman (who worked on “Star Wars” for Reagan) have explicitly warned about the rate of polar warming.
I’d hate to think our government was keeping important information secret. But I’d like to think scientists with access to such hypothetical secrets would say everything they could and hope to be heard.
Just guessing of course.
Hank,
From my reading of the Maslowski presentation I linked to above Maslowski’s reasoning seems to be fully open: Model scale/Heat fluxes are the reason for the aggression of his predictions as compared to the results of other modellers.
Personally I fear he has a point, but I hope he’s wrong. Especially as I am watching the jetstream’s influence on our (British) summer with unease, ENSO neutral conditions are now neutral (since May/June – Wolter MEI ESRL/PSD) but our “La Nina Summer” of 2007 seems to be repeating itself. I am uneasy but unsure if that means anything, I hope I’m wrong and it means nothing.
addition to 751: the “best concise” summary I have been able to find is this link
http://www.ncdc.noaa.gov/paleo/abrupt/data2.html
and fig. 3 indicates that the temperature anomaly tracks the calculate July 65N insolation, which varies from 400 to 500 w/m2 over the past 350k years.
About why it’s every fifth cycle, well, “area of active research”.
A few interesting Terra/Aqua images. (Hope RC staff don’t mind)
Once again to appreciate them you need to open in 250m resolution, which means images of the order of 6Mb! I save all the large images I view and have found that viewing them as negatives via photo manipulation software helps find the ice amongst the cloud.
For all the following use the small orientation image on the left hand bar of the NASA page to find your way, bearing in mind that the short edges are bent round, so you’re really only getting a band up the middle and losing some area on the edges.
Image 1 gives a visual feel for the concentrations you’ll see on AMSRE.
For those following the Bremmen AMSRE images you’ll have noted the low concentration area following 165E longitude line in towards the pole. You’ll find that on the top middle of the image, following along at 45deg down from the middle and you’ll see more breaks in the cloud with low concentration as that area reaches toward the pole.
If you go down from the middle you’ll reach the line of islands (Severnaya Zemlya, Zemlya Fransfa-Losifa, Svalbard). Again from the AMSRE images you’ll have noted that between those islands and the 165E longitude region is an area of ~100% concentration, so you can see what that looks like.
Also the following 2 images compliment each other nicely and show a larger swathe of the central arctic than has been visible for a while.Image 2 and
image 3.
Still too much cloud for the North West Passage, as far as I can see anyway.
#759 Jerry,
That’s quite a good page.
I hate to hit you with an actual paper. But Gerard Roe’s “In defence of Milankovitch” is one that first struck me as elegant and neat when I first read it. I think it will help you. Don’t worry too much about the text unless you want to, it’s the graphs at the end that may be of interest.
There’s an adobe pdf file, available here.
On page 14 figure 1 shows the relationship between ice volume (black traces) for two different records of ice volume (A & B) and the green trace which is insolation (INcoming SOLar radiATION) at 65degrees North lattitude. There is no clear relationship.
The neat thing Roe did was to compare the rate of change of ice volume and 65degN insolation (figure 2). When looked at like that there is a pretty good fit. And because ice is white and reflects sunlight, the changes in the ice sheets would have affected global temperature.
Then Roe points out that if you just take the June 65 degN insolation you get a very near perfect fit (figure 3). Roe notes that this does not explain everything, but it explains a lot of the observed changes.
This doesn’t mean CO2 had no role to play, merely that the most likely initial cause was the effect of sunlight on ice-sheets. With CO2 having a secondary amplifying role, notably away from the northern ice sheets. So unlike today*, CO2 was not a cause but an effect that then amplified the initial changes ultimately due to orbital “wobble”.
*CO2 is not the only cause of human driven climate change, although it’s a substantial one.
Re: 760
I find using the 7-2-1 banding on the NASA MODIS images really separates the clouds from the ice. This is only available from down to 500 meters however, but it really brings out the contrast.
The latest satelite pictures are getting scary as that ice is getting in bad shape.
Something else that may be worth considering is that the ice may still cover the North Pole at the end of the melt season, however if we get the right wind and storm conditions, some areas that will probably be free of ice at 85 North, may actually get pushed the 300 miles to the pole right up to mid October.
So it may not all be over by September 15 after all.
Cobbly, According to Cryosphere graph:
http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/current.365.jpg
2008 sea ice extent is about to catch up with 2007.
Big puzzle for me is NASA GISS not getting any data for the warmest zone in the Arctic, the Archipelago, which surely affects their average…
http://data.giss.nasa.gov/cgi-bin/gistemp/do_nmap.py?year_last=2008&month_last=7&sat=4&sst=0&type=anoms&mean_gen=07&year1=2008&year2=2008&base1=1951&base2=1980&radius=1200&pol=reg
Its been a strange year for trends.
RE 759
You wrote:
“This doesn’t mean CO2 had no role to play, merely that the most likely initial cause was the effect of sunlight on ice-sheets. With CO2 having a secondary amplifying role, notably away from the northern ice sheets. So unlike today*, CO2 was not a cause but an effect that then amplified the initial changes ultimately due to orbital “wobble”.
*CO2 is not the only cause of human driven climate change, although it’s a substantial one.”
Please don’t mix an analysis over hundreds of kiloyears with what has taken place over past 150 years. The mechanisms and conclusions are different. The study you refer to does nothing in explaining AGW.
This chart from the US Navy gives an interesting way to view global warming and polar amplification.
https://www.fnmoc.navy.mil/ncoda_web/dynamic/ncoda_1440x721_global_anom.gif
[Trust their certificate :-]
Cheers, Alastair.
Re #763 where Lauri wrote:
Although glacial cycles last around 100 kiloyears, the terminations when temperatures rise from a minimum to a maximum, take only a few thousand years, and in the northern hemisphere such temperature changes can happen in around three years (3 not 3,000.)
We are fairly confident that the glacial cycles are due to oscillation in the earth’s orbit which are smooth. Therefore the abrupt climate changes must be due to an amplifying factor, which is most likely carbon dioxide since there is a strong correlation between it and temperature.
Most of the CO2 on earth is dissolved in the oceans and when they warm, the dissolved CO2 is released into the atmosphere. Thus a rise in CO2 can produce a rise in temperature, but also a rise in temperature can cause more CO2. There is a real danger that if we increase the CO2 in the atmosphere by burning fossil fuels, then we may cause the oceans to release even more leading to a runaway greenhouse.
HTH,
Cheers, Alastair.
Hi there. Can anyone point me to discussion on potential or observed physical responses to the continuing disintegration of Arctic sea ice? For example, could lack of ice, or changes in timing of ice pack formation and ablation somehow trigger changes to thermohaline circulation?
Rando, the sea ice is salty in any case. Moreover, even the Greenland glaciers are probably not enough to significantly affect the THC. Europe’s Winters are probably safe for now.
re: Cobbly (760), Laurie (763), Alister (765):
Cobbly, thanks for the paper pointer. I will take some time to digest it.
Laurie & Alister, my reason for asking in this forum is that the rapid decay of Arctic ice, most noted in 2007 but observed (less spectacularly) for over 20 years, reminded me of the rapid (decades?) retreat of the last North American ice sheets that my kids asked about.
If I get the rate of change sorta right, (from the NCDC.NOAA link) it took ~10k years for insolation to move from 420 to 480 W/m^2 (+15%) in July insolation at the time of the last glacial retreat. Just does not seem like a rapid enough power change to directly melt kilometer thick ice sheets, especially mid-continent, where ocean currents are not present to bring warm water from the topics. So the atmosphere must have warmed, or wind patterns shifted, to bring more heat northward.
The change in insolation may have provided the energy, but Alister’s point is that it had amplification. Alister argues that increased insolation allowed CO2 to be released from the ocean, and that the CO2 effects acted as the amplifier. OK, but still, that seems too slow a mechanism for the reported northern hemisphere climate shifts (as little as 3 years).
My impression is that the last glacial retreat happened comparably, or faster than the current Arctic melt is occurring. Maybe this impression is wrong; if so, let me know.
So I’m trying to get a sense for what possible mechanisms (climate or weather) could bring that much power to the task of melting that much ice at the necessary rate. As distasteful as it is to invoke catastrophes like comets, I can’t exclude them (how much debris of a strike would remain if it hits a kilometer thick ice sheet?) as possible accelerators to more gradual processes. Or maybe the ocean currents reorganized (why?), altho that (to my mind) seems like a thousand-year process. The fact that the glacial retreats match every 5th insolation cycle tells me it isn’t just that single factor.
I’m working on the mental model that the longer term (decades) current melt of Arctic ice is due (mostly) to increased heat transport in the oceans and secondarily by atmospheric heat transport.
Kids ask the darndest questions…
#763 Lauri,
Agreed. Roe’s paper is not about the current situation.
My sole purpose in that paragraph: In the current context of obfuscation and denial about the radiative forcing impact of CO2, it is important never to allow misunderstanding to lead to the incorrect conclusion that because CO2 was an effect of wider processes in glacial/interglacials it is not a driver now.
In stating the matters previous to that final paragraph as Roe’s conclusions, and not doing so for the final paragraph I trusted that seperation to be implicit. Thanks for giving me the opportunity to make it explicit.
#762 Wayne,
It looks like I’m wrong again, at least I have been consistent: In consistent under-estimation of the situation.
I think you’ll find that in the months to come more data will be incorporated into the GISS dataset. I have noticed that the most recent month is always more patchy then preceding months.
#761 LG Norton,
Thanks for the advice. As for what happens next, we’ll see. This is actually a more interesting year than last.
#766/767 Rando/Ray,
I’m more concerned about atmospheric circulation than ocean as a potential impact. I agree with Wunsch’s interpretation of wind forcing’s dominance upon ocean circulation (but as I’m an amateur that means little). I do not think changes to thermo-haline subduction will be significant in terms of European climate and Northern latitude heat transports (I presume that’s behind your “winter” comment Ray?). I am waiting to see what the scientific and meteorological community have to say with regards any impacts from thinned and fragmented ice.
The kids in your class will like this one, if they haven’t seen it already. Lots of info available if they ask their librarian to help them find it.
http://www.nsf.gov/discoveries/disc_summ.jsp?cntn_id=109768
Jerry,
The mechanism that drives the degaciation is not fully understood yet. One reason is that it must be complex to include both a 10,000 year and also three year episodes. If it was simply just an asteroid impact, for instance, we would have discoverd that by now.
The second reason is that the climate models are wrong. That is why every second post by Gavin is to argue that the models are correct despite the evidence to the contrary. The mistake the modelers are making is to believe that the greenhouse effect from gases operates high in the atmosphere. In fact the greenhouse gases absorb the terrestial radiation in the air next to the surface. Check out Beer’s Law. More greenhouse gases means more absorption and heating of the air close to the surface so melting the ice.
So the following is a plausible sequence.
Recently a paper was published that showed that the deglaciation begins when the solar radiation in southern hemisphere is at a maximum. This warms the surface there, which is mainly ocean, and so releases CO2 which warms the globe, but espcially the tropics where the warmer and wetter climate leads to more methane (CH4).
This increase in CO2 and CH4 melts the margins of the NH ice sheets, which creates water vapour, another greenhouse gas. James Hansen has argued that melting ice sheets are wet, and this accelerates their demise. Moreover as they retreat the land exposed becomes boggy generating more methane.
What the greenhouse gases are doing is raising the snow line both in latitude and in altitude. As the ice sheets are undercut, they become lower and eventually their top surfaces melt. That reduces the sunlight reflected from their surfaces (albedo.) This is the main cause for the inclease in absorbed heat which melts the ice, not the increased solar radiation due to the 20,000 year astronomical cycle.
About 7,000 years after the SH solar max., the NH is then approaching its solar max and the ice then melts vigourously. As it disappears the warming from change in albeo and the greenhouse gases melts the sea ice which has been covering the North Atlantic. Sea ice melts evenly and disappears suddenly causing the abrupt wamings that are recorded taking only three years. See recent paper on entry into Holocene and into the Bolling-Allrod.
If this scenario is correct, we need not fear a cooling, but rather a warming when the Arctic sea ice disappears.
HTH,
Cheers, Alastair.
Gack. Alastair, of course greenhouse gases absorb near the ground. Because the ground is where all that sunlight is being averaged out into warmth. That emits infrared. Greenhouse gases absorb the infrared And reradiate, or get agitated and crash into and warm up all the sourrounding non-greenhouse oxygen and nitrogen. Which collide with the greenhouse gases. Which absorb imapact energy and radiate some as infrared.
And so it goes. At every level. As below so above, up to the altitude and thin air where the photons have a fair likelihood of departing the planet without running into anything else, and the greenhouse gases can actually get rid of some of the heat energy.
But ya gotta come up with an experiment that will show one result if theory A is correct, and a different result if theory Everybodyelse is correct — at least hypothetically, describe how someone would test whether your idea makes any detectable difference.
What difference would it make if you were right?
You need a website to explain this, right now it’s just trickled out all over other people’s blogs and never pulled together anywhere you can point people to.
Save typing!
Jerry, from actual observations, the greatest ingredient to accelerate melting is a warm winter (2006-200, very cloudy), followed by a cloud free summer (2007). Hinting evidence of greenhouse gases giving a boost in warming (more clouds in winter) and also extra heat causes less clouds in summer, I think that summer 08 melt proves that Heat acquired in the atmospheric system does not escape to space even after a reverse scenario (caused by La-Nina and the disappearance of Arctic clouds at solar minima) ….., which is a clear winter and cloudy summer. The atmosphere in itself has a certain level of heat capacity not easily giving away its heat, as some may surmise, the atmosphere and its greenhouse gases play a huge role in this.
Rando, I took a string directly out of your posting above and dropped it into the Google search window and got good answers. You might start here:
http://www.google.com/search?q=f+ice+pack+formation+and+ablation+somehow+trigger+changes+to+thermohaline+circulation
— or start by making up other examples and trying them out
[771, Alastair] – “The mistake the modelers are making is to believe that the greenhouse effect from gases operates high in the atmosphere.”
I think you misunderstand what the models do. They certainly have greenhouse gases acting at the surface, but at surface temperature and pressure the absorption bands are saturated. This is why early 20th century scientists didn’t think the extra CO2 was going to have a global warming impact, because the effect of additional gases would be nil.
Later in the century it was realised that at the lower temperatures and pressures in the upper atmosphere the absorption bands would not be saturated, and so the extra CO2 would be able to have an increased effect. The details of the fact that the bands are already partially saturated, etc, is why the effect of extra CO2 on radiation is logarithmic and not linear.
So, if you look at the total forcing from CO2, it is certainly true that a lot of it acts near the surface, but if you look at the change in the forcing, between now and pre-industrial, this occurs mainly higher up.
So I don’t think there is any fundamental mistake in the climate models here. Having said that, I am surprised by how broad the uncertainty range is for CO2 radiative forcing in the IPCC reports.
CT today reports NH sea ice area of 4.001 Mkm^2, lower than the 2005 minimum of 4.01 Mkm^2.
http://arctic.atmos.uiuc.edu/cryosphere/iphone/images/iphone.recent.arctic.png
Nick, just eyeballing it, that curve looks like an exact repeat of last year’s.
Depending on if you are measuring sea ice area or extent, you get number ranging from 200,000 to 600,000 more ice this year than last year.
We might end up at the end of the melt season, with conflicting numbers on if the 2007 minimun was beat.
It does not matter scientifically, however it does matter if you had a bet on it (I do not).
On another note. The Canadian ice service declared the southern route of the North West Passage open for navigation on August 14.
The Northern Route thru Perry Channel is now down to 7 tenths ice for about 180 km, so I imagine in another week or two, the Northern route will be open.
The Canadian Ice Service is a Department of Environment Canada, and they are always practiceing due dillegence; so I imagine the conditions are better than they say.
http://igloo.atmos.uiuc.edu/cgi-bin/test/print.sh?fm=08&fd=14&fy=2007&sm=08&sd=14&sy=2008
August 14 sea ice extents compared for 2007 and 2008. If you go on to look at the September data for 2007, in simplistic terms it looks as though everything that’s shaded yellow through to red on the August 14 map eventually melted out. Now look how much of this year’s remaining ice is in similarly poor shape. If things follow a similar trajectory, the Arctic could be in for a real world of hurt this year. I wouldn’t yet betting against a new record low for either extent or area.
Also, in more trivial “gosh wow” terms – the pattern of ice melt is sufficiently different this year that it looks to this (uninformed) bystander as if the Northwest and Northeast passages will be simultaneously open. When was the last time that happened, if ever?
LG, There is actually one expedition which is already there…
http://www.69nord.com/english/expe/logbook.html
A sail boat, reporting a few wind driving floes… I think its looking more and more like 2007
http://www.seaice.dk/iwicos/latest/amsr.n.comb.20080814.gif
despite significant weather differences. The underlying , invisible, if you like, force behind all
this is heat in the atmospheric and ocean systems, almost oblivious to weather when it comes to Arctic Ocean ice it seems, so it appears to be a true metric of GW.
Wayne,
I think that you are correct about it be the underlying forces which are behind it all. As I see it, these underlying forces are ice thickness and ocean salinity :-)
The thickness depends on whether the ice is first or multi-year ice. Since there is little thick multi-year ice left, then the melt will continue rapidly until the end of September, eating its way through the remaining first year ice.
When the ice melts, it alters the salinity of the ocean surface because produces fresh water which has a higher melting/freezing temperature than sea water. It is also less dense and floats on the top of the ocean. The big melt last year left a lot of fresher water on the surface of the Arctic ocean which readily froze during the winter. The result was that the spring ice extent in 2008 exceeded that in the spring of 2007.
I don’t have a convincing explanation of why the 2008 melt did not accelerate in June as happened in 2007, but it seems that in 2007 the Parry Channel was free of ice by August, allowing the fresh melt water in the east Arctic to flow across the surface and drain out into Baffin Bay and the Atlantic Ocean.
I argue that the accelerated 2007 melt slowed towards the end of August when all the first year had gone and the thick multi-year ice began to melt. As already explained, this year that will not be a problem, and now the Parry Channel is effectively clear. Thus the current accelerated melt will continue up until the end of September when the North Pole receives no more solar energy until next spring.
So, Hank et al., I have put forward a proposition which can be disproved. If the Arctic ice does not continue to melt for another month, then my theory may be wrong!
Cheers, Alastair.
Wayne and LG: here’s another sailor taking the southern route, more-or-less accompanying the one to which Wayne links:
http://baloumgwen.canalblog.com/
Alastair, ya, that fooled a lot of contrarians who saw the newly formed January 2008 vaster ice as an excuse to deny Global Warming. I support your idea that it was from fresh water, certainly as I like to mention, polar ocean old ice makes a splendid cup of tea, very salt free indeed. I am a bit interested in the biology under this new vast ice area, I think we are quite ignorant about it,
because huge seasonal variances never happened before in recent history. The topography makes it different than Antarctica, we can only observe what happens from this. But I am wondering if for the near future the ice will have in its “DNA” the same characteristics of Antarctic ice which disappears every summer.
For near future consequences, a repeat of 1997-1998 is in the cards,
when EL-Nino raged hot, if this happens again with current wide open Polar water, another mild
winter like 2006-07 will happen, what is left of old ice will doubtfully survive.
What is happening now is compression of the ice, opening up suddenly vast areas, I dont like:
http://nsidc.org/data/seaice_index/images/daily_images/N_timeseries.png
NSIDC extent number, it is not giving a good idea, if the ice was thoroughly scattered last year, instead of being highly compressed, 15% extent could have easily covered the entire Arctic ocean, and there would have been a coverage of 100%…..
I like an exact percentage of how much ice is left is a better figure. Lets settle on a good measurement instead of being confused by all these distractions. The ice has melted extensively already.
Finally I have a beef with the surface temperature record at present, it is not reflecting
true nature of heat in the atmosphere, current polar ice melt proves this. So your theory
will ultimately fail if you use current surface temperature record. Splendid idea to use the ice instead.
RE # 781 Alastair, you said:
[The result was that the spring ice extent in 2008 exceeded that in the spring of 2007.]
The NH sea Ice Extent graph:
http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/current.area.jpg
shows 2008 extent at the top of the melt season as 14 million sq km and the 2007 as approx 13.3. If the 2008 melt equals or exceeds the 2007 extent, more ice will actually melt in 2008–more fresh water but similar open ocean extent compared to end of 2007 melt season. It is the additional fresh water I am focusing upon.
John McCormick
Gentlemen, have you had a look at the Danish and/or Bremen sites today?
http://www.seaice.dk/iwicos/latest/amsr.n.comb.20080816.gif
http://www.iup.uni-bremen.de:8084/amsr/amsre.html
Wayne, can you elaborate further on this:
“Finally I have a beef with the surface temperature record at present, it is not reflecting true nature of heat in the atmosphere, current polar ice melt proves this. So your theory
will ultimately fail if you use current surface temperature record. Splendid idea to use the ice instead.’
Steven Goddard has recently published another article on the Register’s web site.
http://www.theregister.co.uk/2008/08/15/goddard_arctic_ice_mystery/
The methodology and some of the claims seem erroneous to me, and so I wanted to find out how exactly he arrived at his 30% figure. It says, “The 30 per cent increase was calculated by counting pixels which contain colors representing ice.” but that’s somewhat vague. Were the background pixels (text, legend, border, stars) removed? If so, how? How was the fact that the Sahara desert on this picture
http://igloo.atmos.uiuc.edu/cgi-bin/test/print.sh?fm=08&fd=12&fy=2007&sm=08&sd=11&sy=2008
(which I assume was the source he used — he didn’t actually say) is the same color as used to indicate some of the sea ice at the pole?
I see that he has occasionally posted here, so I thought I’d try this in addition to using the Reg’s “email the author” mechanism.
Even eyeballing those pictures, you can see that the number of pixels of ice-covered ocean is clearly substantially higher this year. I strongly suspect this is an artefact of spatial averaging and the low resolution of the pictures at
http://igloo.atmos.uiuc.edu/cgi-bin/test/print.sh?fm=08&fd=12&fy=2007&sm=08&sd=11&sy=2008
I don’t know what resolution the NSIDC use for their analysis, but the pixel size of the UIUC images must be of the order of hundreds of kilometers across. Look how much of that ice is at ~50-60% concentration. At a higher resolution, that will resolve into ice floes (100% cover) and open areas (0% cover), and various concentrations in between. The poor resolution of the images Goddard used gives a misleading impression of the health of the Arctic ice cover. To take a silly example, you could use a single pixel that covers the complete Arctic Ocean, and declare that for every month on record, this pixel has had over 15% concentration, therefore there has never been any change in ice extent, not even a yearly cycle!
In any event, he’ll end up looking a prat in a month’s time when all the red fragmentary ice from the pictures he favours melts out over the next month.
> Goddard
This is a great example of a point where it would be wonderful if there were a forum that would invite the people who produce those charts together to discuss what Goddard is saying about them.
A line on a graph and a colored chart, both based on rather extensive data sets, shouldn’t be compared like this. The data should be compared instead.
Goddard looks at the pictures, then reasons from those that he can determine the numbers behind them and say how much they differ.
WTF?
Alastair, you’re kidding, right? Or left out something?
> If the Arctic ice does not continue to melt for another month,
> then my theory may be wrong!
If the Arctic ice does not continue to melt for another month, everyone’s theory will be wrong. When has it ever stopped melting in August?
__________________________
ReCaptcha says: “William Fairhaven”
Uh, oh. I’m starting to think the programmer behind reCaptcha is using something like Google’s ad-placing text analysis. This is just too good.
http://coleccionctb.museothyssen.org/coleccionctb/eng/htm/obra10/ficha.htm
William Fairhaven Bradford.
Okay, look at the plate for August 18th, plate number 8:
http://www.clarkart.edu/exhibitions/bradford/kiosk/index.html
Tenney #785 There is no way possible to have a cooling of the atmosphere without having some sort of evidence in the Polar ice melt. Although some contrarians are again fooled, gullible on purpose, and use very little analytical prowess to figure out that 2008 is the equivalent, if not a greater melt than 2007….. Despite Low pressure systems affecting ice compression by causing winds opposing the Arctic Gyre current, compression by synergism is something that actually accelerates a melt like in 2007, in addition despite summer time clouds and also an incredible late winter bout of clear skies…. The melt is huge… So the surface temperature record does not reflect total atmospheric heat. Here is something to consider, temperatures measured over an icy surface during summer is not the same measurement of a temperature reading over rocks, land and water during the same season, akin to the Urban heat bubble. There is something amiss, only a calculation of the entire troposphere weighted temperature gives a good reading comparable to total heat content. For those who cant do that, use the sun disk as a fixed sphere of reference,
and watch it expand over the years, because there is less refraction in warmer air.
RE: #787 Peter Ellis says:
“I don’t know what resolution the NSIDC use for their analysis, but the pixel size of the UIUC images must be of the order of hundreds of kilometers across.”
Actually, I traced back through and the NSIDC data is based on 25km grid data. The NSIDC data is derived from a NASA data and not the other way around as the Goddard article incorrectly asserts. I went to
http://nsidc.org/arcticseaicenews/
and clicked on the link labelled “about the data” under the picture that was reproduced on the Reg’s site. The NSIDC site says:
Second, the U of I data (which he mentions, but doesn’t link to) is at http://arctic.atmos.uiuc.edu/cryosphere/. If you look at that page it says “Snow and ice data provided by the National Center for Environmental Prediction/NOAA.” I am guessing that is the same data that is at ttp://polar.ncep.noaa.gov/seaice/Analyses.html but it’s not clear to me if that’s correct. It seems Goddard wasn’t clear on that either, since he says that the U of I data is based on the NSIDC data, which doesn’t seem to be correct. Anyway, on that NOAA site, if you click on “How the ice grids are constructed” and you get a full page of detailed information on just that topic, including the sentence:
In other words, the data ultimately derives from the exact same instrument used to make the graph on the NSIDC’s web site. So if there’s a difference, it has to be in the processing and interpretation of that data.
To see if there really was “something odd” in the NSIDC data (which is what the Goddard article claims) I downloaded the 2007 and 2008 daily data from
http://nsidc.org/data/docs/daac/nsidc0051_gsfc_seaice.gd.html
and wrote a program to interpret the images and count grids with >= 15% ice. I found that on 8/12/2007, this program calculates that there was 5.54563 million square km of sea ice and for 8/11/2008, I get 6.2775. Now first, I’m comparing the near real-time data with the final data which isn’t exactly apples to apples. Second, I’m calculating area and not extent (a distinction which Goddard’s article muddles). Third, I’m not sure that my calculation regarding the missing data area just at the pole is correct (the NASA web site says that there is an area of 0.31 km^2 right at the pole which is not “seen” by the instrument. For this calculation, I assumed that area was entirely ice.) Even with all those caveats, that’s a difference of 13% in area, which is pretty nearly exactly the percentage difference in extent which the NSIDC’s web site shows, so my analysis agrees much more closely with the NSIDC data than with the Goddard article.
That’s why I want to understand exactly how Goddard’s 30% figure was derived.
Re Steven Goddard,
Yet another tour-de-force of his incapacity to opine on this matter.
It’s notable that Goddard didn’t show Cryosphere Today’s area plot:
http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/current.365.jpg
Which doesn’t support his “nothing to see here” nonsense.
That the melt has sped up and gained on last year this late in the melt season seems to suggest a role for thin ice. Granted, as NSIDC noted in Sea Ice News on 11 August, wind patterns have had a role. But thicker ice would be less responsive to such impacts.
The difference between the area(Cryosphere Today) and extent(NSIDC) is that:
*Area is the sum of pixels with over 15% sea ice concentration weighted by the percentage ice coverage in that pixel.
*Extent is the sum of pixels with over 15% sea ice concentration.
Hence the extent at minima is always greater than area, and I argue that as the ice gets thinner in the years to come area will probably drop faster than extent. As the ice gets thinner concentration will drop and extent may miss that because more pixels will be less than 100% but more than 15%. That’s why I use area(CT) not extent(NSIDC).
By pixels I am talking about the base derivation from raw data used by CT/NSIDC, not using pixels off the end product (as Steven Goddard appears to have done to get his dubious 30%).
In post 725 I went over the state of play in terms of area. Here’s a reworking of that, reading figures from Cryosphere Today’s “recent ice area” and “hemispheric ice area” plots, all in million square km (rounding up from the minima and down from the maxima – i.e. conservative):
3/2007 13.3
now 2007 3.1
9/2007 3.0
3/2008 13.9
now 2008 3.4
The lag between 2008 & 2007 at current date 3.4 – 3.1 = 0.3
Melt up to now 2007 and 2008
2007 13.3 – 3.1 = 10.2
2008 13.9 – 3.4 = 10.5
i.e. so far this year the overall area melt from maxima has been greater this year than last.
RE: #792
Thanks for the clarification about area and extent calculations. Based on this, I updated my program to derive both from this NSIDC data:
http://nsidc.org/data/docs/daac/nsidc0051_gsfc_seaice.gd.html
My area graph now agrees very closely with
http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/current.365.jpg
except that my data is not smoothed (e.g. missing data from the near real-time data set is counted as no ice in my plot).
I agree that it doesn’t make too much sense to count pixels from the end product at the Cryosphere Today site, but that’s apparently what Mr. Goddard did. I’m hoping he’ll respond and let me know exactly how he obtained his 30% number.
Cobbly , The chap is an attention seeker, but instead of paying for an argument, for say 1 pound. LOL Monty P. !… He gets it for free… It looks more and more like 2007, at an incredible late pace. Can’t say for certain how its going to end yet, but looks like 08 melt will beat 07, not only in melt extent but it might exceed last years record.
I looked at your MET office sea-ice prediction animation again, with now 2
seasons extreme melt in retrospect,
http://www.metoffice.gov.uk/research/hadleycentre/models/seaice_anim.html
A1B scenario has it wrong by consistently showing a greater melt from the Russian side (the side with the thinnest ice). This model should be checked as to why it does so. But I suspect that its integrating the surface temperature projection with ocean temperatures, and fails to mimic what is going on now, 2 years running… When will we see A1C?
Hi Wayne,
For myself on that issue; the relevant Monty Python sketch has to be “Deja Vu”. ;)
I’ve been using Env Canada HRPT timeseries trying to get a lucky allignment of Terra/Aqua with frontal breaks in the cloud over McClure Strait and Viscount Melville Sound. No joy so far, the cloud is just too thick (even with LG Norton’s 7-2-1 ban hint). For me it’s superfluous, AMSRE and SMRI are good enough for me to conclude the northern NWP is virtually ice free, if nothing else I’ve got a good feel for how visual and those images match up – Bremmen’s AMSRE are damn good! But a visual of open water in Melville/McClure would be cool.
There are some very large areas of loose ice out there in the ocean, as we both know that can open or close given the right winds. If either index is more likely to meet/beat last year I’d say CT’s area (partly because of the state of the ice). But it’s now a case of wait and see as far as I’m concerned. I certainly didn’t expect it to be this close.
CT’s area index is still on a straight line trajectory, which stuns me, if I suspect it’s about to start to reduce the rate of loss that’s only because I’m expecting it (time of year). There is no more deviation from a straight line than there has been since start of June. CT seems to have a time lag, their area plots don’t show halfway through August, yet it’s the 17th now. Bremmen shows notable loss in the last week (Chucki/E Siberian//Laptev), that’s disappearance(melt) not dispersal. AMSR SST from JAXA/EORC shows 4-5degC anomaly warming in the areas they’ve not excluded as possibly containing some ice for this August.
JAXA/EORC: http://sharaku.eorc.jaxa.jp/cgi-bin/amsr/polar_sst/polar_sst.cgi?lang=e
Ed Beroset,
I’ve never tried to deal with raw data as you’re doing, that’s mainly because I’m aware of how many caveats there are and how little I know. That’s not meant as a criticism, it really is good to see you having a go. With regards the November 2007 extent discrepancy you mention – could it be partly because NSIDC were applying a monthly averaging? There’s a note about them switching to daily figures on their recent Sea Ice News pages.
As for Steven Goddard, did you know he turned up here? (Late-400s and 500s of this thread) While browsing through the comments on his article I saw a further comment from him strengthening my suspicion about his 30%. I suspect he may be using some code to numerically processes the images from Cryosphere Today. I agree, best go to the real data if that’s what one is trying to do. He’s got a channel on You Tube (stevesgoddard) with some videos that are even more obscure than the solitary one I posted there earlier this year (under my name CobblyWorlds). I might pull my finger out and do some more, but knowing me I probably won’t.
CobblyWorlds, check out this Terra shot from Friday:
http://rapidfire.sci.gsfc.nasa.gov/realtime/single.php?2008228/crefl1_721.A2008228194500-2008228195000.2km.jpg
There’s thin cloud/fog cover, but I think you can pick out the contrast between the floes and the water, showing mostly open water right through Melville Sound.
Guys,
The Danish site’s links change every day and even throughout the day, but if you get a chance look at this ENVISAT — shows all the slush:
http://www.seaice.dk/iwicos/latest/envisat.GMM3d.n.20080818.gif
ReCaptcha: Pringle women LOLOL
#797 Nick Barnes,
Thanks for that. I’d missed it: Due to work pressures I’m very likely to miss things at the end of the week.
#798 Tenney Naumer,
Picasso does the Arctic! ;)
Thanks for the link Tenney, The Danes and Bremen seem to capture ice conditions better, if you take that shot and compare with cryosphere which seems a tad conservative. It looks like the North EAST passage will open soon as well, something that happened last year for a day or 2.