quest4peace
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Holes in ice and snow filling in really nicely
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http://www.ijis.iarc...ice-monitor.cgi
Nice shot of the extent and concentration as of yesterday
You can clearly see the parts of the ice that need to thicken, and fill in a bit more in the main body,(they look a bit like jigsaw piece edges to me) which is holding the "Area" back, Is that right? but i'm hoping that will improve. Extent looking a lot less miserable now though.Ice AREA anom finally lowering, according to cryosphere today,
http://arctic.atmos....edu/cryosphere/
2.4 million off the norm still though.
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Thanks muchly for taking the time
that's quite a clear explanation I just need to digest it a bit and i'll have it worked out -
I think you're a little confused there.
Area and extent are just measures of how much of the ocean surface is covered by ice, so it says nothing about the thickness.
I was going to type out a detailed explanation about the difference, but remembered that songster explained the difference very well before. So after a little search, here's the post he made back in January
so essentially, at the moment there are large areas that are under 100% concentration, which the extent will count as being 100% covered, but the area measurment will count the actual ice cover (once it's over 15%).
Does that help?
I am feeling really dense here
is it only me that is having a problem working out how the area and concentration measurement works I read somewhere that if you think of the ice as like a piece of swiss cheese in places, and If you were to slice through, you would see the holes that are distributed through it revealing that the concentration of the cheese isn't 100%? that being the case with regard to the ice, when these "holes" are filled in the concentration goes up, and then when it reaches the 15% level the satellite reports it as cover? I understand that as brine is filtered out of the ice, it leaves pockets of air which results in the ice being less dense until the air escapes?, Am i half way there? -
We've probably got a lot of ice that's not much over 15% concentration. So while the "extent" measurements would count this as completely ice covered, the "area" measurement will, instead, count the % of ice cover over 15%, giving it a lower value.
At least that's what I think is causing the big difference.
We're now 117k above the 2007 with daily NSIDC extent, after a huge increase of 282k!
That means we've averaged 174k/day over the last week and have added over 1 million km2 in the last 6 days.
Remember that the NSIDC graph uses a trailing 5 day average, which still hasn't passed 2007, but likely will tomorrow or Friday.
So even though the extent is rising,it's only a comparatively thin layer at the moment, and needs to build some depth to get itself above the 15% concentration mark
.After which the area total will hopefully start to rise?. What do you think of the upturn in extent rise at the moment? it is becoming quite phenomonal for now at least Record high "extent" at winters end?. I'm wiling the concentration level up now as well -
Nope, just seasons. When the CO2 stops working, you'll be tunnelling through ice sheets to work
We're looking very close to a new record anomaly for global sea ice area
Always something to remind us that the ice extent rise at the moment tints our sunglasses a bit. What is affecting the area increase at the moment? is it the relatively warm SST'S still?
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Hi Q4P!
I agree that predictions should be received as just that and not 'beliefs'. Many folk are saying that the ice will drop below the 1 million 'seasonal' threshold by 2020 and ,were this to prove true, the WWF map would be wrong with any ice surviving the melt not being solely to N. Greenland/C.A.
We saw this year (for the first time?) The north shore of Greenland shed over 2m of ice through Aug. I'm sure this is to do with shallow water and albedo flip allowing early warming of the coastal fringe (we also saw a lot of ice from glacier tongues/shore-fast ice shed along that strip)> I was also frequently advised , through spring , that the C.A. had 3m ice that would not melt out but we saw what occurred there? The only problem there came from basin ice entering the north of the main 'deep channel' route otherwise it would have been clear sailing through there since early Aug??
Throughout the basin we have seen the 'old' perennial ice nurseries change into places that now consume perennial ice and i fear the same will become true of Greenland's north shore. With the remaining ice either positioned differently to this year or 20km smaller in diameter the NW Passage would have been fully open for over 1 month so I cannot see how ice would be expected in there once the basin is 'seasonal'?
As I say any remnant ice will occur where the unique weather pattern allows it to and this may well be different each passing year?
Hi Gray Wolf
Hope i don't contradict myself when i post long reply's i'm still getting my head round things This is what NOAA has for 2035 some 5 years earlier than WWF
2020 is only 7 1/2 years away so as ever we'll have to wait and see, the ice will do whatever it's going to do that's the only thing i can say is definite, regardless of our predictions for the worse or the better. I'm a big believer in what the WWF amongst other environmental charities are doing, there message is meant with the best of intentions. And was just taken rather aback at the sea ice prediction map. I was thinking to myself that,there isn't multiyear ice sustained in C.A right now, so what was their prediction based on for that area in 2040?. Not sure about the thin slither grasping onto northern greenland either? Surely it wouldn't be that extreme?. I would like to think that a lot can change in 28 years time and i hope that the horrific map never comes to pass as the effects on the wildlife up there would be horrendous let alone the ripples elsewhere
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A very impressive jump in the IJIS extent yesterday, +296k! This takes us 155k above 2007.
That's an increase of over 1 million km2 in the last week, and over 530k in the last 3 days.
That is absolutely brilliant, and huge!!
Surely were breaking some refreeze records at the mo?. -
Well if you extrapolate from a short period it looks 'plausible' but you should always look at longer periods to establish trends - see news thread.
Also it's a good idea not to make predictions about subjects which are not fully understood, because when the prediction is completely wrong later, people will assume that everything else you say is probably inaccurate and/or exaggerated..
Surely a lot can change between now and 2040?.They have done so much good work around the world for wildlife and such.With regards to the 2040 Arctic ice prediction, a big organisation like WWF is taking a risk with their integrity with these predictions
I'm sure part of it is scare tactics with good intentions to get their message across.Strangely enough, I partly agree with 4wd.
It is best to look at the long term to get an idea of where things are headed. The WWF image doesn't really say how much of the year they expect to have so little ice left for, which doesn't help with working out how realistic the prediction is.
I think we can say that it's quite likely that we'll have seasonal see ice by then, as many of the models (which have predicted way too much ice so far) have us pretty close to it by then.
I will disagree with 4wd with regards making predictions though. Almost every prediction is going to be wrong to a certain degree. But with every wrong prediction comes an opportunity to learn what went amiss. As long as your prediction is based on solid science and not political ideology (i.e., North Carolina sea level rise, I mean, "recurrent flooding") it should be respected and as long as you learn from your mistakes and admit when you got things wrong, people shouldn't think less of you imo
What worries me is the fact that the C.A just this year melted out, let alone be multi year ice in 2040. just thought id see what people thought.
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Has anybody seen this WWF September min extent ice map from the year 2040?? bit o.t.t?
As the climate warms, Arctic sea ice is disappearing.
Almost every summer, the amount of remaining ice gets smaller. That summer ice is vitally important to a whole range of animals from tiny shrimp to vast bowhead whales, and to local people.
One stretch of ice is projected to remain when all other large areas of summer ice are gone. This is the Last Ice Area.
http://wwf.panda.org.../last_ice_area/
Where is the Last Ice area?
This map shows the extent of summer sea ice projected for 2040, as viewed from the north pole. The prediction is for a fringe of ice to remain in Northeast Canada and Northern Greenland when all other large areas of summer ice are gone.
They reckon there will be a small slither around the top of greenland and C.A in 2040 is that a bit far fetched??
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Hi guys, found this on you tube
It's the 2012 melt season up to the start of refreeze may to september, North Pole Web Cam 2012
I
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Another big increase on the NSIDC extent again today, this time up by 165k to 5,500,430km2, to put us just 56k off 2007.
Once more, a similar increase tomorrow will have us even with 2007.
We've added 940k in the last 6 days, which ain't too bad!
On the other hand, we have beaten the record -ve anomaly again on Cryosphere Today, now 2.709 million below average.
A lot of positives out of a relatively bad situation at the moment
The area anomaly is rather worrying though with it spiraling lower and lower below norm, as i now understand a bit better,that the area at end of refreeze will have the main bearing on the ability of the ice to sustain itself during the summer melt out.Also not forgetting the sst anom effects come melt. -
It's the proverbial "Bawhair" away from passing 2007.
From mid September, it has been following more or less the same gradient as the 2008 plot.
very apt scottish expression right there
Can't comment on the thickness, but would love the depth to get better as well -
The angle of that line is good viewing at the moment, it's almost vertical
Can it continue? -
As well as being a little behind, Cryosphere Today measures sea ice area, which is always lower than extent.
If you're not familiar with the difference between extent and area, it's explained quite well here http://nsidc.org/arc...aq/#area_extent
Got to be honest
I didn't realize i was reading Cryosphere today so wrongly, i wondered why the extent graphic wasn't having any affect on the line graph for the better? i will have a read through that link thank you. I see now that they are two different things, and the anomaly graph is "area" and not indicating extent anomaly From the link provided by BFTV
I quite like this explanation for anybody else who is like me on this subject
Frequently Asked Questions on Arctic sea iceArea and extent are different measures and give scientists slightly different information. Some organizations, including Cryosphere Today, report ice area; NSIDC primarily reports ice extent. Extent is always a larger number than area, and there are pros and cons associated with each method.
A simplified way to think of extent versus area is to imagine a slice of swiss cheese. Extent would be a measure of the edges of the slice of cheese and all of the space inside it. Area would be the measure of where there is cheese only, not including the holes. That is why if you compare extent and area in the same time period, extent is always bigger. A more precise explanation of extent versus area gets more complicated.
Nice shot from the Amsr2 satellite ice concentration and extent graphic today the area in siberia north of the Kamchatka Peninsula has a link of sorts to the main body now
http://www.ijis.iarc...ice-monitor.cgi
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Just when things are beginning to look up eh!
Instead of catching 2007, on Cryosphere Today we slowed down enough to set a new anomaly record, of 2.706 million km2 for the 13th of October, beating the previous record set in October of 2007. This has also put us back more than 200k below 2007.
On to the NSIDC, and some good news!
The extent here increased by a massive 226k yesterday, up to 5,335,170km2, which also takes the 5 day mean above 5 million. This brings us to 2.8 million below average, (less than 1 million off the 79-11 average annual minimum), and now just 73k off the 2007 extent. A similar extent increase tomorrow would have us pretty much equal with 2007.
This is simply me asking so please bare with me
but...With most others reporting good increases, is cryosphere today unreliable? or is it simply the fact that it being 2 days behind, there is going to be a discrepancy, of what the more up to date results are reporting anyway? so the anomaly on there isn't a true indication, especially if you can add two hundred to 3 thousand in gains to it's figure, for the days it hasn't caught up to? if that makes sense -
Once we catch 07', the next target is 2000 Avg.
2007 can feel 2012's breath on it at the mo it's so close
I notice though that 2007 rose a bit quicker from this point after a slight lull. I would take 2008's line as the next to aim for i think, as i don't want to get my hopes up I still wonder how much damage those ice breakers have done trying to get to the pole though? -
Further to BFTV's post, the ice is near touching 2007's line now, and it doesn't look like slowing much
Unless sod's law kicks in The latest value : 5,265,781 km2 (October 14, 2012)
Only 8K off your avg of 160K that you thought was required to catch 07. Not bad. If we can catch 07 by next weekend that would be a result.
The upward climb of that line is much healthier, long may it continue. BFTV, didn't you say gains of that magnitude, are few and far between over the past years daily extents? and could we be seeing another above average period of increase occurring
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Loving the spread of the white stuff nowVery good developments. Excellent for the Snow Advance Index.
Every little helps, i'd love to see a not quite so cold version of 2010 in our neck of the woods with more snowyup, thats better, with a fair bit more forecast over the coming days- http://www.weather-f...ps/Russia?hr=6
over=pressure&symbols=none&type=prec
scandi should get some as well- http://www.weather-f...=none&type=prec
But i must try not to get ahead of myself and look at each day as it comes http://www.intellica...cation=RSXX0303
Good view of current russian temps as of 17:00 today the white line being the 0.C line
nice and cold for snow just need the precip does anybody know if that area of cold is going to edge west anytime soon? -
One of the reasons I'd expect the max this year to remain reasonably high is the colder water from the -ve PDO around the Bering strait. Another high extent winter/spring in the Bering sea I'd say, helping to keep things looking respectable by March.
No idea on thickness yet. The PIOMAS model only updates every few weeks, will keep an eye out though.
So the end extent could end up as high as 2011 again
pity the thickness couldn't surge while we have more surface ice Will be interesting to hear how thickness is affected come march/april 2013, need to get those sst's down or there might be another shock next year. That's a while away yet, and i' feel like i'm wishing my own life away at the mo, don't know about you guys . -
If you look at the DMi graph for example the lines tend to converge at Spring and Autumn.
http://ocean.dmi.dk/...icecover.uk.php
The Autumn convergence is quite marked and co-incides with a noticeable 'shoulder' in the graph.
This is when the Arctic Basin is more or less full of ice up to the coast of Siberia and Alaska; increase in area then gets more difficult as the area available at high latitude suddenly drops away.
When is the time during refreeze, when the ice enters it's best chance of increasing it's thickness? and what can scupper this depth development? I know underlying heat in the ocean seems to be one of the main things people talk about, but is this the only factor?
Interesting how 2011 was one of the highest extents at winters end on the graph then to see how far it fell from that position to a new record min in sept It really does seem the final "extent" of any year doesn't guarantee a higher minimum extent in sept. -
I think it's definitely possible, just unlikely. My best guess would be that we catch some of the previous years around mid-November.
On the record IJIS record, only 6 years since '79 averaged over 100k/day from now until months end. Only 2 of those we over 140k/day (2007 and 1995) and none have been over 150k/day, so it kinda gives you an idea of how exceptional the growth rate would need to be to catch 2007!
Odds seem quite low for October at least it seems, maybe november will give some cheer
Any idea how the thickness is getting on?. -
Just 221k behind 2007 now on the IJIS data set. The average gain from now until the end of the month in 2007 was 148k/day (nearly 2.7 million in the next 18 days!), so we want to be averaging over 160k/day to catch it.
Looking at how the refreeze has gone so far, do you think it is possible, we could achieve this figure of increase needed as we've done so well to catch back up to 2007? Could we catch any of the others in your opinion
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We are half way through the month now and I didn't think we would get this close to the 2007 plot. I thought it was a bit ambitious to catch it by now, but, it's done remarkably well.
I'm finding myself willing it on now
the angle of climb looks like it slowed a little in 2007? and our current years line is looking a bit steeper will it slow down as well? or will we be pleasantly surprised Hopefully the latter please.I do still think behind 2007 at all is atrocious, but let's see
but i'm hoping that will improve. Extent looking a lot less miserable now though.
that's quite a clear explanation I just need to digest it a bit and i'll have it worked out 
is it only me that is having a problem working out how the area and concentration measurement works
I read somewhere that if you think of the ice as like a piece of swiss cheese in places, and If you were to slice through, you would see the holes that are distributed through it revealing that the concentration of the cheese isn't 100%? that being the case with regard to the ice, when these "holes" are filled in the concentration goes up, and then when it reaches the 15% level the satellite reports it as cover? 
I'm sure part of it is scare tactics with good intentions to get their message across.
i will have a read through that link thank you. I see now that they are two different things, and the anomaly graph is "area" and not indicating extent anomaly 
It really does seem the final "extent" of any year doesn't guarantee a higher minimum extent in sept.
Arctic Ice Discussion (the Refreeze 2012-2013)
in Climate Change
Posted · Edited by quest4peace
Got there eventually
I think i just needed to look at it more simply then i was 
Good to finally pass 2007 on both counts now 
And i know some people will be reluctant to get excited yet, staying on the worst case scenario outlook (for good reason). Wouldn't it be nice if it surprised us? 
I do, but i don't want a severe winter here (can't believe i said those words)
A very cold one would do,but it doesn't have to be -20 again, just enough for a nice amount of snow, gas bills will be too high this year anyway.