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Gray-Wolf
06 February 2011 17:15:15

Done so Aim but I'm struggling to sense you're point?


 


Koyaanisqatsi
ko.yaa.nis.katsi (from the Hopi language), n. 1. crazy life. 2. life in turmoil. 3. life disintegrating. 4. life out of balance. 5. a state of life that calls for another way of living.
VIRESCIT VULNERE VIRTUS
AIMSIR
06 February 2011 22:50:38


Done so Aim but I'm struggling to sense you're point?


 


Originally Posted by: Gray-Wolf 

Looks like I'll have to back off on this one Gray Wolf.I've had a look around and it does seem to be the case that crocs and other such reptiles could once survive a number of months of darkness in the Arctic region.


I would have thought it highly unlikely.


Apologies.

Gray-Wolf
07 February 2011 08:04:59

No worries Aimsir! I too find it quite an incredible thing but then the Muggah's in India kind of 'hibernate' the dry season (or migrate great distances to find a river) so maybe they laid up over winter/dark?


It's the same for the plants that need 10c or above, they still have that dark to get over each year. The massive amount of heat that the oceans must have transported then is mind boggling but if some of the mid ocean ridges were not as much of an obstacle to the basal cold currents maybe we did have such a heat transfer ?


Another low figure for ice gain today? I really thought we might have seen a rapid build of peripheral ice over these final weeks of winter but it doesn't look like it wants too? I was not studying the ice with such interest back in 06' so I don't know how the end of that winter was stacked weather wise (anyone any pointers?).


Koyaanisqatsi
ko.yaa.nis.katsi (from the Hopi language), n. 1. crazy life. 2. life in turmoil. 3. life disintegrating. 4. life out of balance. 5. a state of life that calls for another way of living.
VIRESCIT VULNERE VIRTUS
Essan
07 February 2011 14:23:18

It was once theorised that deciduous trees evolved in the Arctic - leaf shedding in autumn occuring because they had no need of them once the sun set.  This is no longer thought to be the case, but nontheless it's a nice idea. 


Since many animals and plants survive within the Arctic Circle today I see no reason why the darkness would be a problem for different animals and plants, under warmer climates, in the past   Though I'm sure some may have hiberated or migrated.


Andy
Evesham, Worcs, Albion - 35m asl
Weather & Earth Science News 

Anyone who is capable of getting themselves made President should on no account be allowed to do the job - DNA
Gandalf The White
07 February 2011 15:07:50


Since many animals and plants survive within the Arctic Circle today I see no reason why the darkness would be a problem for different animals and plants, under warmer climates, in the past   Though I'm sure some may have hiberated or migrated.


Originally Posted by: Essan 


Migrating plants, now there's a thought....


Triffids anyone?


Location: South Cambridgeshire
130 metres ASL
52.0N 0.1E


AIMSIR
07 February 2011 23:42:08



Since many animals and plants survive within the Arctic Circle today I see no reason why the darkness would be a problem for different animals and plants, under warmer climates, in the past   Though I'm sure some may have hiberated or migrated.


Originally Posted by: Gandalf The White 


Migrating plants, now there's a thought....


Triffids anyone?


Originally Posted by: Essan 

No thanks Gandalf.


I've heard they are quite nice in a salad though.but a bugger to keep on the plate.

AIMSIR
07 February 2011 23:57:14


No worries Aimsir! I too find it quite an incredible thing.


Originally Posted by: Gray-Wolf 

Just a small revisit Gray Wolf.Do you think plate tectonics or movement of the Earths crusts could have an influance on what might be found fossilised in the Arctic?.Like if fossils laid down in an area way to the south could have moved into the region over millions of years.


I'm off to bed now and tired,.(hope I don't dream about Gandalf's Triffids)


Can't say I know a lot about the subject other than some basics.Could be worth a look at though.

Gray-Wolf
08 February 2011 08:10:41

I'm sure it was a slow drift north for the exotics (from 65 to 55 million years ago) but we also had the Atlantic opening up and I'm not sure whether the Panama isthmus was land yet either (so tropical Pacific waters flowed into the Atlantic?). all these 'extra features' may have allowed a type of oceanic heat transfer that is not open to us today?


I'm sure that the fall in temps at the end of the optimum didn't give the same opportunity for a slow drift back towards the equator for our lions and Hippo's and the Arctic Croc's!!


Anyhoo's , another slow day in the Arctic yesterday. not sure if it's peripheral losses balancing out general gains or whether there is a basin wide reason for the slowdown?


Jumping again (must be the coffee?) The full moons last year were march 1st and 29th and you can see the rise in extent start just before when the moon was 'full' (max tide height?). I'm not a coast dweller so am not intimate with the tides but I imagine ,just like the moon itself?, the tidal increase is a growth day on day towards the max figure?


If we do have a basin of 2m ice;


http://topaz.nersc.no/topazVisual/matlab_static_image.php?action=NA_ARC_NWA_Function&file_prefix=ARC&match_date=20110203&depth=0005&variable_name=hice


 as the above appears to show?,then will the height of the spring tide lift it beyond it's elastic limit and fracture it into slabs?


EDIT: http://www.woksat.info/etctb07/tb07-1336-f-arc.html


The above shows the current (yresterday) state of South Beaufort and you can see last years rounded flows at the entrance to McClure straight (bottom left) and also the 'scallop' shaped leads behind (the same type of feature as you find at the entrance to Nares?) Is this picking out the flow of water below the ice (from Bering through the NW Passage and out into Baffin)


EDIT;EDIT; Talking of Baffin, here is the Baffin area on Feb 3rd;


http://www.woksat.info/etctb03/tb03-1418-f-grn-w.html


you can see the odd 'bright' return in the north with last years ice frozen into this years ice. The rest is F.Y. ice. note the 'look' of the ice and it's fracture patterns. Now check out other 'Arctic images' from Wokingham;


http://www.woksat.info/wos.html


are you also seeing a lot of similar conditions throughout the basin? (if not try here http://www.woksat.info/etcta25/ta25-1230-h-grn-n.html, check out the 'wave' patterns over the pole heading/pointing towards Fram)


Koyaanisqatsi
ko.yaa.nis.katsi (from the Hopi language), n. 1. crazy life. 2. life in turmoil. 3. life disintegrating. 4. life out of balance. 5. a state of life that calls for another way of living.
VIRESCIT VULNERE VIRTUS
AIMSIR
08 February 2011 11:53:49

Hi Gray Wolf.
I was more wondering if the fossils left there were a result of tectonics or continental drift.
You are right about the(moon's) tidal increase effect being a day on day increase towards the max.
I reckon it might have an effect in the condition of sea ice and costal land ice.But would this be reversed as the moon wains.I wouldn't be too sure if it could also effect the whole arctic sea ice region at once.
As to your last point it certainly looks like there is some fracturing going on in places.Will these cracks close again as the tide drops?.Just guessing they might.


edit:Baffin does look to be in a bad state.Can't see it getting any better this year i'd have to admit.

Gandalf The White
08 February 2011 17:34:35


Hi Gray Wolf.
I was more wondering if the fossils left there were a result of tectonics or continental drift.
You are right about the(moon's) tidal increase effect being a day on day increase towards the max.
I reckon it might have an effect in the condition of sea ice and costal land ice.But would this be reversed as the moon wains.I wouldn't be too sure if it could also effect the whole arctic sea ice region at once.
As to your last point it certainly looks like there is some fracturing going on in places.Will these cracks close again as the tide drops?.Just guessing they might.


edit:Baffin does look to be in a bad state.Can't see it getting any better this year i'd have to admit.


Originally Posted by: AIMSIR 


I'm not sure that the damage is reversible as the moon wanes.  It's a bit like wondering if the glass you dropped whilst drunk will miraculously be back in one piece when you sober up....


Once the ice is fractured I would have thought that any re-freezing at the edges will be less strong that the original slab and therefore more suspectible to further wave motion - and a point of weakness come the melt season.


As you say, the ice doesn't look great. In terms of extent, the maximum is potentially less than 3 weeks away now. I am increasingly pessimistic that this year will be close to or below 2006.


Location: South Cambridgeshire
130 metres ASL
52.0N 0.1E


Gray-Wolf
08 February 2011 19:53:45


As you say, the ice doesn't look great. In terms of extent, the maximum is potentially less than 3 weeks away now. I am increasingly pessimistic that this year will be close to or below 2006.


Originally Posted by: Gandalf The White 


I'm just gonna agree G.T.W. , I went further but it even had me a tad depressed so I deleted it!


Must be bad when the likes of me are backing off from posting the obvious?


With all the cold drivers in place why are we seeing this? PDO-ve is supposed to help LaNina do it's cooling and ,with solar still pitifully low, you'd have expect some kind of 'rebound' at least???


I'll let the skeptics fill in my blanks in understanding (they seem more 'up to speed' on the 'cooling to come'?).


Koyaanisqatsi
ko.yaa.nis.katsi (from the Hopi language), n. 1. crazy life. 2. life in turmoil. 3. life disintegrating. 4. life out of balance. 5. a state of life that calls for another way of living.
VIRESCIT VULNERE VIRTUS
Marcus P
08 February 2011 21:06:35



I am increasingly pessimistic that this year will be close to or below 2006.


Originally Posted by: Gray-Wolf 


I'm just gonna agree G.T.W. , I went further but it even had me a tad depressed so I deleted it!


Must be bad when the likes of me are backing off from posting the obvious?


With all the cold drivers in place why are we seeing this? PDO-ve is supposed to help LaNina do it's cooling and ,with solar still pitifully low, you'd have expect some kind of 'rebound' at least???


I'll let the skeptics fill in my blanks in understanding (they seem more 'up to speed' on the 'cooling to come'?).


Originally Posted by: Gandalf The White 


I'll fill in your blanks for you: I put this on another thread, but it goes better here.


The (at least partially ENSO-induced) late 20th C warming decades are very likely (good IPCC expression, that) to have helped initiate/prolong/exaggerate the reduction in arctic sea ice. Such negative anomalies (your links leave us in no doubt) only cause positive feedbacks to surface temperature increase and sea ice reduction, at least in the short-term: "the lowest January ice extent recorded since satellite records began in 1979" means "unfrozen areas of the ocean continued to release heat to the atmosphere" (http://nsidc.org/arcticseaicenews/2011/020211.html).


That’s happening all winter, every winter. In summer, reduced ice cover not only reduces Earth's albedo but also allows the (increased area of) open ocean to gain more incoming short-wave solar radiation.


So there you are: inevitable positive feedback. You couldn’t possibly expect instant restoration of temperature levels. As TomC has often said, in periods of anomalously warm SSTs the oceans (and therefore the climate system) are actually losing heat (to the atmosphere and thus to space). This happened during the ENSO positive period, and is happening now due to the reduced arctic sea ice cover. The current La Nina will be offsetting this of course. Eventually the oceans’ net heat loss should become apparent via negative SST anomalies and the atmosphere will begin its inevitable response (though slightly diminished by the impact of CO2).

Ulric
08 February 2011 21:25:17

How sure are you that it isn't, "The (at least partially AGW-induced) late 20th C ENSO decades are very likely to have helped initiate/prolong/exaggerate the reduction in arctic sea ice"?


To doubt everything or to believe everything are two equally convenient solutions; both dispense with the necessity of reflection. - Henri Poincaré
Marcus P
08 February 2011 21:49:10


How sure are you that it isn't, "The (at least partially AGW-induced) late 20th C ENSO decades are very likely to have helped initiate/prolong/exaggerate the reduction in arctic sea ice"?


Originally Posted by: Ulric 


Who knows the amount of contribution? Who knows the true attribution of late 20th C warming? Warming has occurred and the ENSO-positive decades formed part of that trend: sea ice reduction has occurred: feedback has occurred.

Stephen Wilde
08 February 2011 22:36:08

In the late 90s and right up to 2007 the Arctic sea ice was being melted from below after 30 years of strong El Ninos eventually circulating around to the Arctic Ocean reaching a peak effect in 2007.

Now with more meridional jets the ice recovery is being slowed down by the increased flows of warm air to the Arctic.

In due course the negative PDO acting via stronger La Ninas will cool the water entering the Arctic and the ice recovery will strengthen despite the continuing meridionality.

It is just the reverse of what happened in the previous cycle.

In the early 70s the Arctic ice was growing to a high level from the cooler ocean waters flowing to the Arctic.
Eventually a more positive PDO raised the temperature of the water reaching the Arctic and the warm water started to cut under the Arctic ice in the 80s and in due course the melting began despite the zonal pattern.

Just as the zonal air circulation pattern delayed melting back then the meridional pattern is delaying the recovery now.

All this has happened before and all this will happen again.




Gandalf The White
08 February 2011 23:26:29




All this has happened before and all this will happen again.



Originally Posted by: Stephen Wilde 


Sorry Stephen, you do not know this for a fact and you most certainly do not know that the current rate of change has occurred before.  It is just another unsupported statement.


 


Location: South Cambridgeshire
130 metres ASL
52.0N 0.1E


Gandalf The White
08 February 2011 23:29:14



How sure are you that it isn't, "The (at least partially AGW-induced) late 20th C ENSO decades are very likely to have helped initiate/prolong/exaggerate the reduction in arctic sea ice"?


Originally Posted by: Marcus P 


Who knows the amount of contribution? Who knows the true attribution of late 20th C warming? Warming has occurred and the ENSO-positive decades formed part of that trend: sea ice reduction has occurred: feedback has occurred.


Originally Posted by: Ulric 


Precisely Marcus, which should be a cause for concern or at least something short of a complacent assumption of normality, surely?


I think it's a long and unsound logic jump to go from 'who knows' to 'it is insignificant' or 'it is perfectly normal'.


We are back to risk assessment yet again.  If you don't have certainty about something how is the correct response to assume it is nothing to be concerned about?


 


Location: South Cambridgeshire
130 metres ASL
52.0N 0.1E


Marcus P
09 February 2011 04:14:26



Who knows the amount of contribution? Who knows the true attribution of late 20th C warming? Warming has occurred and the ENSO-positive decades formed part of that trend: sea ice reduction has occurred: feedback has occurred.


Originally Posted by: Gandalf The White 


Precisely Marcus, which should be a cause for concern or at least something short of a complacent assumption of normality, surely?


I think it's a long and unsound logic jump to go from 'who knows' to 'it is insignificant' or 'it is perfectly normal'.


We are back to risk assessment yet again.  If you don't have certainty about something how is the correct response to assume it is nothing to be concerned about?


Originally Posted by: Marcus P 


And so it must be just as unsound to blame it all on Evil Mankind when there is such uncertainty; just how much of the warming has not been caused by natural fluctuation and natural feedback?  Wait and see is the best strategy at the moment: why Save the World when it is not known if it needs to be saved?

Gray-Wolf
09 February 2011 08:18:03

http://www.ijis.iarc.uaf.edu/en/home/seaice_extent.htm


Sure would be scary if the graph continued flat/down!!!


I've no idea why we should be looking at such poor performance at the moment? Did the new moon fragment the pack and allow for compaction?(but surely the margins left open would just re-freeze unless SST's there won't support it and synoptics aren't favourable for 'freezing'???)


I'd find it difficult to summon the total peripheral cold that we'd need to plump the current extent figure up (there would have to be sectors of WAA to balance any cold plunges to come?) so all I can muster is a continued gently rise (punctuated by 2 'lunar spikes' ) before melt season arrives?


Then we go into the melt season around 1 million short of the past few melt seasons and with an even thinner pack that they started out with.


Do we just average the previous 4 seasons min extents and minus a million sq km from that figure to find our ballpark ''min extent' figure for this summer?


Koyaanisqatsi
ko.yaa.nis.katsi (from the Hopi language), n. 1. crazy life. 2. life in turmoil. 3. life disintegrating. 4. life out of balance. 5. a state of life that calls for another way of living.
VIRESCIT VULNERE VIRTUS
Gandalf The White
09 February 2011 10:31:33


 


And so it must be just as unsound to blame it all on Evil Mankind when there is such uncertainty; just how much of the warming has not been caused by natural fluctuation and natural feedback?  Wait and see is the best strategy at the moment: why Save the World when it is not known if it needs to be saved?


Originally Posted by: Marcus P 


This line of reasoning puzzles me.


We have coastal erosion. It is an entirely natural process.  Do we say "Oh, it's natural so we shouldn't do anything about it?"


We had a threat of flooding in London due to the South-East sinking and water levels rising, increasing the risk when conditions were 'right'.  Did we shrug our shoulders and say "It's entirely natural, we shouldn't do anything about it." ???


In some parts of the world buildings near earthquake zones are designed and built to withstand earthquakes.  I don't recall anyone saying "Earthquakes are natural, we shouldn't do anything."


Of course the key here is about the perceived risk and the much easier link between effect and consequences.


So, please don't try to run the "Is it evil human beings or is it natural" argument, because clearly we do choose to combat natural threats.  The issue is solely about perception of the risk and identification of the consequences.



 


Location: South Cambridgeshire
130 metres ASL
52.0N 0.1E


Ulric
09 February 2011 13:53:01


And so it must be just as unsound to blame it all on Evil Mankind when there is such uncertainty; just how much of the warming has not been caused by natural fluctuation and natural feedback?  Wait and see is the best strategy at the moment: why Save the World when it is not known if it needs to be saved?


Originally Posted by: Marcus P 


Where do you consider the uncertainty to lie?


To doubt everything or to believe everything are two equally convenient solutions; both dispense with the necessity of reflection. - Henri Poincaré
Marcus P
09 February 2011 17:01:40


This line of reasoning puzzles me.


We have coastal erosion. It is an entirely natural process.  Do we say "Oh, it's natural so we shouldn't do anything about it?"


We had a threat of flooding in London due to the South-East sinking and water levels rising, increasing the risk when conditions were 'right'.  Did we shrug our shoulders and say "It's entirely natural, we shouldn't do anything about it." ???


In some parts of the world buildings near earthquake zones are designed and built to withstand earthquakes.  I don't recall anyone saying "Earthquakes are natural, we shouldn't do anything."


Of course the key here is about the perceived risk and the much easier link between effect and consequences.


So, please don't try to run the "Is it evil human beings or is it natural" argument, because clearly we do choose to combat natural threats.  The issue is solely about perception of the risk and identification of the consequences.



 

Originally Posted by: Gandalf The White 


Of course we mitigate against the clear effects of nature, and that should include those due to climate change: that is a far different thing from saying we should take all sorts of actions in the belief that as yet unobserved effects might happen if assumptions built into climate models happen to prove correct.

Marcus P
09 February 2011 17:09:21



And so it must be just as unsound to blame it all on Evil Mankind when there is such uncertainty; just how much of the warming has not been caused by natural fluctuation and natural feedback?  Wait and see is the best strategy at the moment: why Save the World when it is not known if it needs to be saved?


Originally Posted by: Ulric 


Where do you consider the uncertainty to lie?


Originally Posted by: Marcus P 


Firstly, in the attribution of recent (20th C/late 20th C) warming. How much of it being due to:   a. 'anthro'-CO2.  b. 'natural' multi-decadal changes.  c. positive feedback (such as via the reduction in sea ice), plus the contribution of any negative feedback processes.  Secondly, in the knowledge of future changes in climate - which are based on climate models which cannot yet model adequately such feedbacks, and which have to make presumptions about attribution.

four
  • four
  • Advanced Member
09 February 2011 19:35:06

Tipping point 'unlikely'
http://www.agu.org/news/press/jhighlight_archives/2011/2011-02-09.shtml#one


new research by Tietsche et al. suggests that even if the Arctic Ocean sees an ice-free summer, it would not lead to catastrophic runaway ice melt. The researchers, using a general circulation model of the global ocean and the atmosphere, find that Arctic sea ice recovers within 2 years of an imposed ice-free summer to the conditions dictated by general climate conditions during that time. Furthermore, they find that this quick recovery occurs whether the ice-free summer is triggered in 2000 or in 2060, when global temperatures are predicted to be 2 degrees Celsius (3.6 degrees Fahrenheit) warmer.


TomC
  • TomC
  • Advanced Member
09 February 2011 20:59:30

and


http://www.agu.org/news/press/jhighlight_archives/2011/2011-02-09.shtml#four


 


Stroeve et al. investigate the causes of the low ice extent in 2010. The authors analyze sea-ice concentrations as well as sea-level pressure and air temperature data from 1979 through 2010 and find that atmospheric circulation during winter of 2009 to 2010 was different from previous negative Arctic Oscillation events. In typical negative Arctic Oscillation events, winds drive thick multiyear ice in the Beaufort Sea northward to areas where the ice thickens and survives the summer melt season, but during the 2009 to 2010 winter, winds drove older ice across the Beaufort Sea into the warmer southern areas of the Beaufort and Chukchi seas.


Furthermore, overall ice volume in the Arctic Sea was low at the start of the 2010 melt season. They also note that in recent years, thick multiyear ice in the Arctic has been disappearing and is being replaced by thinner first-year ice that is less likely to survive the summer melt season.

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