quote=Gandalf The White;139877]

It's to do with climate not weather. The argument is about extended snow cover as well you know.

We are in danger of falling out Dave.  This thread is about Arctic ice and the comment about snow cover is irrelevant as well YOU know.  

Increased snow cover over the northern hemisphere this winter is most definitely weather and not climate.   If we have increased snow cover fairly consistently over the next 20 years then come back and remind me that it is now fair to classify the change as climatic.

 

. Arctic ice cannot be discussed without implications elsewhere and the diminishing extent is being sold by some in this thread as the harbinger of an imminent climatic disaster. This is certainly a possibility. The topic of the thread, has for long, been used to support or deny AGW, with some disinterested.. But, it has been an argument put by me and Stephen especially that ice extent in the Arctic is possibly connected to mid latitude cold and indicating more expansive winter snow cover and extended seasonal snow cover. The "argument" referred to, is about climate and not weather. The Arctic ice extent change is being discussed as a climate change indicator, not just a statistic that changes - and rightly so. There are some who collect statistics like collecting stamps - thats fine but this thread is not only for them.

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Did we not have record 'high' snow levels across the US last march? Didn't we then have record 'low' levels by mid May? Snow is not ice and is not on ocean. As well all know so well snow ,without -10 air above it , melts real fast!!!

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Did we not have record 'high' snow levels across the US last march? Didn't we then have record 'low' levels by mid May? Snow is not ice and is not on ocean. As well all know so well snow ,without -10 air above it , melts real fast!!!

Yes, but the point is that snow is very good at reflecting the sun's radiation back into space. And if snow cover becomes more extensive and lasts longer, then albedo is increased and temperatures tend to drop.That is of course if everything else stays the same.

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Yes, but the point is that snow is very good at reflecting the sun's radiation back into space. 

But a lot of it doesn't get to space any more because it is absorbed by the extra CO2 in the atmosphere and re-radiated downwards.

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Yes, but the point is that snow is very good at reflecting the sun's radiation back into space. 

But a lot of it doesn't get to space any more because it is absorbed by the extra CO2 in the atmosphere and re-radiated downwards.

But more energy is radiated back into space from land with snow cover than without it.

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Yes, but the point is that snow is very good at reflecting the sun's radiation back into space. 

But a lot of it doesn't get to space any more because it is absorbed by the extra CO2 in the atmosphere and re-radiated downwards.

But more energy is radiated back into space from land with snow cover than without it.

I don't think it's that simple Polarwind.With regards to either side of the dedate.

It could be,But I doubt it.

Yes, but the point is that snow is very good at reflecting the sun's radiation back into space. 

But a lot of it doesn't get to space any more because it is absorbed by the extra CO2 in the atmosphere and re-radiated downwards.

...not solar radiation, either incoming or reflected.

Yes, but the point is that snow is very good at reflecting the sun's radiation back into space. 

But a lot of it doesn't get to space any more because it is absorbed by the extra CO2 in the atmosphere and re-radiated downwards.

But more energy is radiated back into space from land with snow cover than without it.

But as Ulric says, more (than was the case before AGW) is reflected back.

Not sure what point you are querying here?  Ulric's point is entirely valid - AGW has an effect on the additional energy reflected back from snow and ice and therefore higher levels of CO2 are relevant to the physics.

 

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Yes, but the point is that snow is very good at reflecting the sun's radiation back into space. 

But a lot of it doesn't get to space any more because it is absorbed by the extra CO2 in the atmosphere and re-radiated downwards.

But more energy is radiated back into space from land with snow cover than without it.

But as Ulric says, more (than was the case before AGW) is reflected back.

Not sure what point you are querying here?  Ulric's point is entirely valid - AGW has an effect on the additional energy reflected back from snow and ice and therefore higher levels of CO2 are relevant to the physics.

 

I think ',how relevent' might be the crux of some of the problems we have here Gandalf.

The range of relevency is too broad, imo.for it to be taken seriously.

Science, for sure ,relieves the doubt as such, to a degree but the expanded/global/timescale effect is still questionable? would you not agree?.

I think ',how relevent' might be the crux of some of the problems we have here Gandalf.

The range of relevency is too broad, imo.for it to be taken seriously.

Science, for sure ,relieves the doubt as such, to a degree but the expanded/global/timescale effect is still questionable? would you not agree?.

Hello AIMSIR, I wondered where you had gone. 

I think everything is 'questionable' - if you attribute the meaning that everying is subject to question or challenge.  As you say the issue is to what degree.  Everyone accepts the theory of gravity (unless you are reading this whilst bumping around on your ceiling....) and pretty much everyone accepts the theory of AGW.  The problem lies in the detail, in the feedbacks and the sensitivities.

So, we have a new theory being tested that the loss of ice in the Arctic is resulting in a change in the synoptics in early winter, driving Arctic air into mid latitudes and milder air into the Arctic.   What is that if not a positive feedback and a form of 'chaos' in the sense that the climate is responding differently - assuming the theory is proved correct.

Personally I will stick with the core message of climate change, which is that when you tamper with something as complex as the climate system you should not expect linear responses and as a result you are likely to see more chaotic behaviour.  I think it is clear that we are beginning to see more chaotic behaviour, but some people cannot see the proverbial wood for the trees.

 

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I think ',how relevent' might be the crux of some of the problems we have here Gandalf.

The range of relevency is too broad, imo.for it to be taken seriously.

Science, for sure ,relieves the doubt as such, to a degree but the expanded/global/timescale effect is still questionable? would you not agree?.

Hello AIMSIR, I wondered where you had gone. 

I think everything is 'questionable' - if you attribute the meaning that everying is subject to question or challenge.  As you say the issue is to what degree.  Everyone accepts the theory of gravity (unless you are reading this whilst bumping around on your ceiling....) and pretty much everyone accepts the theory of AGW.  The problem lies in the detail, in the feedbacks and the sensitivities.

So, we have a new theory being tested that the loss of ice in the Arctic is resulting in a change in the synoptics in early winter, driving Arctic air into mid latitudes and milder air into the Arctic.   What is that if not a positive feedback and a form of 'chaos' in the sense that the climate is responding differently - assuming the theory is proved correct.

Personally I will stick with the core message of climate change, which is that when you tamper with something as complex as the climate system you should not expect linear responses and as a result you are likely to see more chaotic behaviour.  I think it is clear that we are beginning to see more chaotic behaviour, but some people cannot see the proverbial wood for the trees.

 

Still here old chap.lol on the gravity effect.

Just a little more pensive these days.

In reply to your linear argument,have things changed?.

The origional forwarding from the IPPC as regards climate change due to Co2 increases is linear.

Should we now expect chaos as is the norm for weather (short term) .To be concidered climate change.

I find the broad band explanations and predictions unacceptable and as yet unreliable,as tweaking seems to be a major factor through the years.(to make things fit the theory)

Just an opinion.

(all that said,a repeat of 2007 would be a cause for concern)

http://rapidfire.sci.gsfc.nasa.gov/realtime/single.php?2011063/crefl1_143.A2011063215500-2011063220000.1km.jpg

Here is the South Beaufort Sea and the northern coast of Alaska. Once upon a time the Beaufort Gyre made this a stronghold for the Paleocrystic. Once up on a time the 'shore fast' ice would run into the massive old floating ice islands of Paleocrystic ice. Prof Barber told us all what he encountered in his sept 09' trip there and we all saw the last 'plume' of Paleocrystic ice die in the waters there last July/Aug. Look at it today! figure the width of that major lead and note the level of fragmentation there.

How do we think this will look in Mid June?

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Yes, but the point is that snow is very good at reflecting the sun's radiation back into space. 

But a lot of it doesn't get to space any more because it is absorbed by the extra CO2 in the atmosphere and re-radiated downwards.

But more energy is radiated back into space from land with snow cover than without it.

But as Ulric says, more (than was the case before AGW) is reflected back.

Not sure what point you are querying here?  Ulric's point is entirely valid - AGW has an effect on the additional energy reflected back from snow and ice and therefore higher levels of CO2 are relevant to the physics.

 

The point StuN makes Gandalf, is that, it is Longwave radiation that is partly absorbed by CO2. Solar radiation, if reflected back, goes back into space. - So increased snow cover, both spatially and timewise will reduce the sum of incoming energy and if this scenario continues will possibly outweigh direct CO2 forcings and also lower, IMO, the level of water vapor in the atmosphere. This would start to put limitations on the positive feedbacks of CO2. Do you have any further thoughts about about outgoing longwave? radiation from Arctic open waters exceeding incoming solar radiation over the short summer months, at low altitude as compared with energy relected bach in mid latitude areas of increased snowcover?

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Yes, but the point is that snow is very good at reflecting the sun's radiation back into space. 

But a lot of it doesn't get to space any more because it is absorbed by the extra CO2 in the atmosphere and re-radiated downwards.

But more energy is radiated back into space from land with snow cover than without it.

But as Ulric says, more (than was the case before AGW) is reflected back.

Not sure what point you are querying here?  Ulric's point is entirely valid - AGW has an effect on the additional energy reflected back from snow and ice and therefore higher levels of CO2 are relevant to the physics.

 

The point StuN makes Gandalf, is that, it is Longwave radiation that is partly absorbed by CO2. Solar radiation, if reflected back, goes back into space. - So increased snow cover, both spatially and timewise will reduce the sum of incoming energy and if this scenario continues will possibly outweigh direct CO2 forcings and also lower, IMO, the level of water vapor in the atmosphere. This would start to put limitations on the positive feedbacks of CO2. Do you have any further thoughts about about outgoing longwave? radiation from Arctic open waters exceeding incoming solar radiation over the short summer months, at low altitude as compared with energy relected bach in mid latitude areas of increased snowcover?

In essence the hypothesis is that, because there is much more heat in the ocean, that this extra heat will leak away to the atmosphere quicker than new incoming solar energy.  That is logical but only occurs because of the extra heat in the first place and that heat is being transferred into the atmosphere.  That can only, at the margins, reduce the ability of the sea to freeze ("at the margins" meaning the times when that extra heat being released to the air will lift the air temperature above freezing).

The absorption of different wavelengths of light is not my specialist subject and I am content to rely upon experts in this field.

 

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Not sure what point you are querying here?  Ulric's point is entirely valid - AGW has an effect on the additional energy reflected back from snow and ice and therefore higher levels of CO2 are relevant to the physics...

 

...The absorption of different wavelengths of light is not my specialist subject and I am content to rely upon experts in this field.

Well I'm no expert myself GTW, though I studied climate change a bit in my degree. But any guide on the greenhouse effect will tell you that CO2's affect on solar radiation is negligible and it acts in the longwave. Hence solar energy reflected by ice and snow is relatively unimpeded by the atmosphere.

Sorry for the italics, I don't seem to be able to turn it off!

http://topaz.nersc.no/topazVisual/matlab_static_image.php?action=NA_ARC_NWA_Function&file_prefix=ARC&match_date=20110224&depth=0005&variable_name=hice

So, if ice 2.5m or less 'naturally melts out' over an 'average summer' (as we see each year in the Southern ocean) how does an ocean ,surrounded by land do? How much 2.5m ice do we see on Feb 24th plot above? How much 'positive feedback' through dark water do we expect, how much warming of the shallows from land warmth do we get?

Do we see a record low even with an 'average ' summer?

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Do we see a record low even with an 'average ' summer?

I think it is highly probable that sea ice extent this summer will be lower than 2008 (2nd lowest), and a reasonable chance that it will be lower than the 2007 record. Consider these options:

1) {most likely IMO} Global temperatures & ENSO state similar to 2008, slightly positive AO on average during melt season.

If this happens, then sea ice extent in September 2011 should be less than 2008 because it is starting from both a more fragile base and lower extent. Would be beat 2007 - possibly.

2) We get synoptics favourable to melting. If this happens we would probably beat 2007 due to the fragile state of the ice

It will be interesting following the situation during the next 6 months.

There is an interesting point made in the Arctic Sea Ice News analysis of sea ice motion from 02/03/11.

Conditions might not be favorable towards a loss of multiyear ice this comming summer.

See Below.

Typically during a negative AO phase, weather patterns favor the retention of thick ice in the central Arctic and Canada basin, where it can better survive the summer. The negative AO also typically leads to a stronger Beaufort Gyre, which helps move ice from the western to eastern Arctic. There the ice thickens, ridging and rafting against the Siberian coast. 

Last winter, the AO was in its most negative phase since at least 1951. However, slight differences from the typical AO pattern in the location of the sea level pressure anomalies had a significant impact on how the ice moved within and out of the Arctic Basin. During winter 2009 to 2010 the peak pressure anomalies were shifted towards the Barents and Kara seas, which helped transport ice from the Canadian Arctic towards the southern Beaufort and Chukchi seas. Since some of the oldest and thickest ice in the Arctic is found north of the Canadian Archipelago, this atmospheric pattern ended up further depleting the Arctic of its store of old, thick ice as that old ice melted during summer in these southerly locations.

This winter also saw a relatively strong negative AO index during December and January.  However, as we discussed in our January 5, 2011 post, the positive sea level pressure anomalies were centered near Iceland. This led to a more extensive anticyclonic (clockwise) transport pattern than last winter.  This may help keep a more extensive distribution of multiyear ice cover as summer approaches.

We saw the circulation in South Beaufort last year keep the ice in the gyre yet it (multiyear ice) all melted out in-situ. With less ice (thinner) across the beaufort gyre this year even if atmospheric's keep it circulating in the Gyre will it maintain or just melt out (again) in-situ?

EDIT: Prior to our 'supermoon' (from 17th through 21st) I wobder if the pacific tsunami will disrupt the shores along Bering and Okhotsk? We'll see tomorrow  I guess?

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From this graph it would appear sea ice extent is currently about the same as 2007.
http://nsidc.org/data/seaice_index/images/daily_images/N_stddev_timeseries.png 
I will be following the 2011vs2007 trend with interest over the next few months. There is little doubt that the ice is in a more fragile state than 2007, but summer 2007 had a particularly favourable pattern for melting.