Polar Ice

[cooling climate]

Testing, testing

[BornFromTheVoid]

4wd, can you post some links to the reports of "worrying ice loss" in the early 20th century that you mentioned?

[Devonian]

Nothing like this stays the same over long time scales.

Your view of 'normal' is a snapshot from about 1830.

Then the record should show repeated changes to Arctic ice cover on century scales. That evidence is not there.

[Gray-Wolf]

I believe you to be correct Dev. The only evidence we are getting is how 'stable' the majority of the pack used to be with the large areas that were constantly under ice showing the type of flora/fauna (over thousands of years) that you would expect to see there.

The recent collapses of the ice shelfs on the North side of Ellesmere island drained a freshwater lake that held it's own 'unique' Eco system (now lost to the Arctic Ocean) and the slow evolution of some of the life in the lake gave it a min 4,000yr history. Why did this survive all the past 'similar warmings' only to collapse this time?

Again we haul back to the Halocline layer. Where is the explaination for a rapid 50m depth Halocline formation that must accompany past melt/re-freeze cycles on a scale of our current one? we know that it gets destroyed once open to the air and wind/wave action takes over so if we are to believe in past expanses of Arctic Ocean being 'open water' then surely we have to believe that the Halocline suffered a similar fate to today. That said we used to measure it to 50m deep and more so it obviously 'reformed' over a relatively short period (and not the thousands of years we 'used' to understand it took of constant isolation from wind/wave under ice cover).

And then what of the 'berg droppings' from previous melts? We seem to have little problems in dating such evidence and our current melt is allowing lots of large bergs (like those created from the collapsed shelfs on Ellesmere Island) to float out into the Arctic Ocean and melt (dropping their load as they do) but I here of no 'cyclical' drift of Berg Rubble on the floor of the Arctic Ocean so where is it?

Then we get to the shelf/sheets themselves. We are now losing the largest ice sheet of the Canadian Archipelago (Devon Island) and have lost nearly all the shelf ice along the North coast of Ellesmere Island. Evidence from the rock surface (date of last exposure to sunlight) has the shelf ice over 3,000yrs old. Why has this chosen to melt now and in no other 'cyclical melting?.

As Devonian says you will need more than "because I said it did" to prove comparable past melting phases are a regular feature of the Arctic Ocean.

How's about the 'Darwinian' side of the melting with the creation of new species now the impenetrable 'old Perennial' has gone? with as many as 28 different species that could interbreed why are we only seeing such 'cross breeding' now (Harp and hooded seals, Grizzly and polar bear, Beluga and Narwhal) and not over the past 'ice free phases'?

Edited May 24, 2010 by Gray-Wolf

[cooling climate]

The Canadian Press

Published on Thursday, May. 20, 2010 2:23AM EDT Last updated on Thursday, May. 20, 2010 2:24AM EDT

Arctic sea ice is on track to recede to a record low this year, suggesting that northern waters free of summer ice are coming faster than anyone thought.

The latest satellite information shows ice coverage is equal to what it was in 2007, the lowest year on record, and is declining faster than it did that year.

“Could we break another record this year? I think it's quite possible,†said Mark Serreze of the National Snow and Ice Data Center in Boulder, Colo.

“We are going to lose the summer sea-ice cover. We can't go back.â€

In April, the centre published data showing that sea ice had almost recovered to the 20-year average. That ignited a flurry of interest on climate change skeptic blogs.

But much of that ice was thin and new. The warmest April on record in the Arctic made short work of it.

Ice cover has already fallen back to where it was in 2007 at this time of year and is disappearing at a faster pace than it did then. Dr. Serreze said winds, cloud cover or other weather conditions could slow the melt, but he points out that the decline is likely to speed up even more in June and July.

“Will [thawing] this year be particularly fast?†he asked. “We don't know. We really don't know.â€

One of Canada's top sea-ice experts suggests things might even be worse than Dr. Serreze thinks. His data could be underestimating the collapse of summer ice cover, said David Barber of the University of Manitoba. Researchers can't learn anything from satellite data about the state or thickness of the ice.

“What we think is thick multiyear ice late in the summer is in fact not,†he said. “It's heavily decayed first-year ice. When that stuff starts to reform in the fall, we think it's multiyear ice, but it's not.â€

Arctic explorers and scientific expeditions are finding more open water and untrustworthy ice ever, Prof. Barber said.

He pointed out the Arctic continued to lose multiyear ice even in 2008 and 2009, when total ice coverage rebounded somewhat.

True multiyear ice – the thick, hard stuff that stops ships – now comprises about 18 per cent of the Arctic ice pack. In 1981, when Prof. Barber first went north, that figure was 90 per cent.

“This is all just part of a trajectory moving toward a seasonally ice-free Arctic,†he said. “That's happening more quickly than we thought it would happen.â€

Once northern waters are clear in the summer, there will be little difference between navigating the Northwest Passage and the Gulf of St. Lawrence, he suggested.

He recounts sailing through degraded ice in an icebreaker. The ship's top speed in open water was 13.7 knots. Its speed through the decayed ice was 13 knots.

“It was almost like it didn't exist.â€

======================================================================================================

So we are hearing the 'big Guns' in Arctic sea ice predicting possible records this year!

This article is just speculative nonsense, if's buts and maybe's.

"Will thawing this year be particularly fast". Answer "we just don't know, we just don't know".

"when that stuff starts to reform in the Autumn we think its multi-year ice but its not". Of course the

ice that forms in the Autumn is not multi-year ice. DOH.

"What we think is multi-year ice late in the summer is in fact not".Oh I see but back in 1981 when Prof

Barber went to the north pole they were able to accurately measure and distinguish the amount of

multi-year ice in the Arctic.

Did Mr Barber survey the whole of the Arctic that summer. This article is not worth the paper its written

on its just speculation, speculation and more speculation and does not tell anybody anything.

As for Dr Serreze well he was quoted in an article back at the end of March when the Arctic ice had one

of its latest peaks in ice area (and perhaps extent) for many years as saying that there was probably

an over reaction (knee jerk reaction) to the summer melt of 2007 and yet here we are severn weeks

later and he's doing it again.

As for my prediction well somewhere back in one of the Arctic ice threads in March I think it was I made

a guesstimate that the summer melt would remain above the 2009 level come the end of play in late

September (if not earlier) with a figure around 5,500,000km2 and so I will stick with that.

Remember though that if the AO remains negative through the summer then we would expect to see

more melt than would normally be the case. In the fifties and sixties when a - AO was much more

prevelent even though the northern hemisphere winters were a lot harsher ( as was the case last winter)

there was a lot moren open water and melt in the summer than would normally be the case and that

includes at the north pole as has been documented.

Cheers.

[Admiral_Bobski]

I've just spent the past 25 minutes or so trawling through dozens of pages about sea ice decline, but try as I might I can't seem to find any data for either ice volume or ice extent that goes back beyond 1978.

Any help? Links? References? Anything?

CB

EDIT #1 - Okay, I've found this: http://arctic.atmos....t.1900-2007.jpg

Now to find out where they got that dataset from.

EDIT #2 - Interesting pdf (be warned: it's over 20MB!!): http://nsidc.org/pubs/gd/GD-6_web.pdf

The period 1953-1976 comes from a paper by JE Walsh: "A data set on Northern Hemisphere sea ice extent"

Earlier data comes from a variety of sources, so far as I can tell. I'll keep digging since, at present, I am not overly convinced of the robustness of the data prior to 1978 (and, judging by this site, nor should I be).

EDIT #3 - here's a link to the Glaciological Data Report in which JE Walsh's paper can be found: http://nsidc.org/pubs/gd/GD-2_web.pdf I'm just having a read now...

Edited May 24, 2010 by Captain_Bobski

[Solar Cycles]

I've just spent the past 25 minutes or so trawling through dozens of pages about sea ice decline, but try as I might I can't seem to find any data for either ice volume or ice extent that goes back beyond 1978.

Any help? Links? References? Anything?

CB

EDIT #1 - Okay, I've found this: http://arctic.atmos....t.1900-2007.jpg

Now to find out where they got that dataset from.

EDIT #2 - Interesting pdf (be warned: it's over 20MB!!): http://nsidc.org/pubs/gd/GD-6_web.pdf

The period 1953-1976 comes from a paper by JE Walsh: "A data set on Northern Hemisphere sea ice extent"

Earlier data comes from a variety of sources, so far as I can tell. I'll keep digging since, at present, I am not overly convinced of the robustness of the data prior to 1978 (and, judging by this site, nor should I be).

EDIT #3 - here's a link to the Glaciological Data Report in which JE Walsh's paper can be found: http://nsidc.org/pubs/gd/GD-2_web.pdf I'm just having a read now...

You won't CB, due to the fact that we only have 32 years data to fall back on. Crazy really, all this scaremongering based on little evidence. Still that doesn't stop the conveyor belt of nonsense to be churned out daily!

[Gray-Wolf]

Go on then S.C. find us a comparable reduction in sea ice over a 2 week period in that 32 years of data or tell me you cannot!

If we use 30 year 'periods' in looking at climate trends how is this 'trend' looking?

Thanks for your efforts C-Bob! I've been on a similar hunt for a couple of years now and only come up with similar and non of it 'robust?' enough to bring forward (being only 'glimpses' of areas and not the basin as a whole).

[Solar Cycles]

Go on then S.C. find us a comparable reduction in sea ice over a 2 week period in that 32 years of data or tell me you cannot!

If we use 30 year 'periods' in looking at climate trends how is this 'trend' looking?

Thanks for your efforts C-Bob! I've been on a similar hunt for a couple of years now and only come up with similar and non of it 'robust?' enough to bring forward (being only 'glimpses' of areas and not the basin as a whole).

Lets see where we stand come September GW. Cherry picking 2 weeks from 32 years of data, is hardly conclusive of anything!

[MR EXTREMES]

'Normal' , to me ,is a pack with a majority perennial (which we saw the tail end of when we started taking sat. data) that enables the pack to endure the summer with minimal losses.

Abnormal is to have a pack that mimicks the southern ocean ice pack with only bay ice surviving the summer months.

Normal is having a pack that will support the weight of a Polar Bear (who evolved to hunt at the ice holes of seal over the spring breeding season) and not have that area so bereft of ice that the seal pups it hunts end up, brilliant white, on a stoney shoreline with no means of defence.

Normal is having sea ice over shallow,shell fish rich seas so the Walrus can feed from their icy islands above and not have them stranded in great numbers on Arctic/Russian coastlines.

well lets hope we do lose all the polar ice atleast then the polar bears would have plenty to eat they would very much enjoy the change in the eco system,

the eco system will change all the time as long as theres a planet,

so will climate.

we can waffle all day long about catastrophic ice loss but there are much bigger threats in our world.

and as some are pointing out there are massive floors in this topic with clearly no real solution or 100% lergitmate evidence as such.

of coarse as i said its possible this year could see large loses and next year large gains nobody really knows and even if loses do happen there will be a recovery at some point in the future.

oh my the drama continues.

Go on then S.C. find us a comparable reduction in sea ice over a 2 week period in that 32 years of data or tell me you cannot!

If we use 30 year 'periods' in looking at climate trends how is this 'trend' looking?

Thanks for your efforts C-Bob! I've been on a similar hunt for a couple of years now and only come up with similar and non of it 'robust?' enough to bring forward (being only 'glimpses' of areas and not the basin as a whole).

whats the point in this chart look at the way the pretty lines do something different each year thats strange,

thats it were all doomed get ya canoes out lads lol.

Edited May 24, 2010 by badboy657

[Yorkshiresnows]

Then the record should show repeated changes to Arctic ice cover on century scales. That evidence is not there.

We only have accurate Ice measurement data from the last 30 years or so (satellite measurements) .... all in a period of positive PDO state.

There is however, plenty of anectdotal evidence to suggest that there was indeed as much ice loss as now. Proxy data from the middle ages and prior to then (Roman times) have shown at least a possibility that there was low ice up North. Certainly that Northern hemisphere temperatures were consistently high.

The Northwest passage was open in the early 40's and Vikings were for several centuries farming Greenland.

These are all facts and you can look for them yourself, there have been links to books and publications made ... go and read them.

(and GW ...... PLEASE don't give me any rubbish about how the Greenland colonists were 'clinging to existance' ..... even if they were, they survived farmed, fished and traded for many generations ...... where there is now ice sheets present.)

Y.S

[Admiral_Bobski]

Go on then S.C. find us a comparable reduction in sea ice over a 2 week period in that 32 years of data or tell me you cannot!

If we use 30 year 'periods' in looking at climate trends how is this 'trend' looking?

Thanks for your efforts C-Bob! I've been on a similar hunt for a couple of years now and only come up with similar and non of it 'robust?' enough to bring forward (being only 'glimpses' of areas and not the basin as a whole).

You're welcome, GW

That said, how is it that you are able to draw your conclusions about the supposedly unprecedented scale of ice decline if, by your own admission, the existing data are not "robust enough"?

CB

[Devonian]

We only have accurate Ice measurement data from the last 30 years or so (satellite measurements) .... all in a period of positive PDO state.

There is however, plenty of anectdotal evidence to suggest that there was indeed as much ice loss as now. Proxy data from the middle ages and prior to then (Roman times) have shown at least a possibility that there was low ice up North. Certainly that Northern hemisphere temperatures were consistently high.

So, we both had 4wd's variability in sea ice and your consistently high temperatures...

The Northwest passage was open in the early 40's and Vikings were for several centuries farming Greenland.

Misleading. A shallow draft boat specially ice strengthened just made it through in the 40's (or was it 30's?) recent times have seen NW passage with open water, not a fight to get through.

These are all facts and you can look for them yourself, there have been links to books and publications made ... go and read them.

Erm, 'facts' actually, and only after you look up and read some of Jared Diamond's work...

(and GW ...... PLEASE don't give me any rubbish about how the Greenland colonists were 'clinging to existance' ..... even if they were, they survived farmed, fished and traded for many generations ...... where there is now ice sheets present.)

Y.S

Ahh, but there are, and were, ice free valleys in southern Greenland - and ice sheet not that far away all the time. There are places where you can grow potatoes there now as well...

Edited May 24, 2010 by Devonian

[jethro]

There's a wealth of information about ice extent back to at least 1900 in Polyakov's work:

http://www.frontier.iarc.uaf.edu/~igor/

Also proxie records from NOAA suggest reduced ice from c1891 - present. Also 1582 - 1774.

http://www.ncdc.noaa.gov/paleo/metadata/noaa-lake-6204.html

[jethro]

Also:

http://www.arctic.noaa.gov/aro/ipy-1/Data-P1.htm

http://www.history.navy.mil/photos/events/ev-1880s/jeannett.htm

http://www.south-pole.com/arctic00.htm

http://acsys.npolar.no/ahica/quicklooks/looks.htm

[cyclonic happiness]

'Normal' , to me ,is a pack with a majority perennial (which we saw the tail end of when we started taking sat. data) that enables the pack to endure the summer with minimal losses.

Abnormal is to have a pack that mimicks the southern ocean ice pack with only bay ice surviving the summer months.

Normal is having a pack that will support the weight of a Polar Bear (who evolved to hunt at the ice holes of seal over the spring breeding season) and not have that area so bereft of ice that the seal pups it hunts end up, brilliant white, on a stoney shoreline with no means of defence.

Normal is having sea ice over shallow,shell fish rich seas so the Walrus can feed from their icy islands above and not have them stranded in great numbers on Arctic/Russian coastlines.

That the polar bears are on the arctic ice is surely just to take advantage of the current situation of more food opportunties, rather than their evolving to live solely on the ice, after all don't they near the coasts, prefere to come inland and raid human colonies for leftovers and rubbish?

that to me smacks of an opportunist hunter/gatherer, a bit like us.

I know the arctic is named after the bears that live on the ice up there, but surely there have been many times over the past 100k years that they have had to change their plans and move back to the land, they'd still be the biggest predator there, and I'm sure would find plenty to eat.

Edited May 24, 2010 by cyclonic happiness

[osmposm]

That the polar bears are on the arctic ice is surely just to take advantage of the current situation of more food opportunties, rather than their evolving to live solely on the ice.....

I'd have thought the polar bear's permanently white coat (and other changes from its cousin the Brown/Grizzly Bear) strongly suggests that it did evolve to live and hunt primarily on ice and snow, no? I am unable to see any other evolutionary advantage in the variation - indeed, it would be a distinct disadvantage for a predator on a non-white background. If the ice/snow was only seasonal, the fur would presumably have evolved to go white only in winter - like, for example, the arctic fox, arctic hare, ptarmigan and northern populations of stoat. For the same reason most arctic species of seal have evolved white natal fur - to camouflage the pups on the ice where they are born.

I know the arctic is named after the bears that live on the ice up there, but surely there have been many times over the past 100k years that they have had to change their plans and move back to the land, they'd still be the biggest predator there, and I'm sure would find plenty to eat.

Not really - their adaptations to life on the ice & in the sea mean that they are hopeless at land hunting (though they will eat human garbage, with sometimes fatal results). More importantly, their biology is very specialized, and actually needs large amounts of fat - specifically marine mammal blubber - and they cannot derive sufficient caloric intake from terrestrial food. If ice loss forces them ashore in late summer & autumn, they effectively starve, and live on their fat reserves from the spring-summer feast.

As for size, some populations of their Brown Bear relations - in particular the Kodiak - are quite as big as they are, and with terrestrial skills (and more omnivorous biology) would certainly out-compete them.

Edited May 25, 2010 by osmposm

[Devonian]

I'd have thought the polar bear's permanently white coat (and other changes from its cousin the Brown/Grizzly Bear) strongly suggests that it did evolve to live and hunt primarily on ice and snow, no? I am unable to see any other evolutionary advantage in the variation - indeed, it would be a distinct disadvantage for a predator on a non-white background. If the ice/snow was only seasonal, the fur would presumably have evolved to go white only in winter - like, for example, the arctic fox, arctic hare, ptarmigan and northern populations of stoat. For the same reason most arctic species of seal have evolved white natal fur - to camouflage the pups on the ice where they are born.

Absolutely! Such reasoning will take some obscuring...

[jethro]

Isn't evolution a constantly changing phenomena?

As none of us were around when Brown bears evolved into Polar's, isn't it entirely possible that their fur was seasonal to begin with (like the Arctic Hare) but gradually changed to permanently White with the Earth's natural progression between ice ages and the growth of the ice sheets - fossil records wouldn't record such information. Afterall, we know that at some point in time, Crocodiles thrived in the North and Palms grew where there is now perma-frost.

Isn't it therefore also entirely plausible that evolution will once again change with the times with Polar bears perhaps having a seasonal white pelt sometime in the future if the Pole continues to warm?

Evolution is reactionary not predictive, similarly but on a shorter time scale, plants react to weather rather than predict it, hence lots of Autumn berries meaning a harsh winter to come being a myth.

[Devonian]

Isn't evolution a constantly changing phenomena?

As none of us were around when Brown bears evolved into Polar's, isn't it entirely possible that their fur was seasonal to begin with (like the Arctic Hare) but gradually changed to permanently White with the Earth's natural progression between ice ages and the growth of the ice sheets - fossil records wouldn't record such information. Afterall, we know that at some point in time, Crocodiles thrived in the North and Palms grew where there is now perma-frost.

Isn't it therefore also entirely plausible that evolution will once again change with the times with Polar bears perhaps having a seasonal white pelt sometime in the future if the Pole continues to warm?

Evolution is reactionary not predictive, similarly but on a shorter time scale, plants react to weather rather than predict it, hence lots of Autumn berries meaning a harsh winter to come being a myth.

Yes.

But the point is that polar bears being white does strongly suggest their environment has been white. Also, if, as people like to suggest, an ice free Arctic is common or not unusual then we'd not expect permanently white polars bears?

[jethro]

To a point but that relies upon evolution working rapidly, I doubt a depleted ice pack for a couple of hundred years would spark much in the way of evolutionary changes.

[Devonian]

To a point but that relies upon evolution working rapidly, I doubt a depleted ice pack for a couple of hundred years would spark much in the way of evolutionary changes.

Humm, white polar bears in a brown/green environment would surely be strongly selected against? Give it a few generations and I suspect (think a certain moth?) their colour would rapidly be slected towards brown again.

[Admiral_Bobski]

Well, if we're talking about reduced ice (or perhaps an ice-free pole) for a period of maybe 20 or 30 years then would evolution have a chance to catch up? I doubt it somehow.

As for the interbreeding, the encroachment of mankind into grizzly or polar bear territory has changed their behaviour patterns. The fact that grizzlies and polar bears are meeting up with each other and getting it on is only indicative of the fact that they have met each other, which can easily be due to changes in their geographical movements rather than any climatological effects.

This is a prime example of conclusions being leapt to.

(On Jethro's point about berry-laden plants foretelling a cold winter being a myth, it would be more accurate to call it an indicator. The reason the old wives' tale grew up is because, historically, when such plants are heavily laden with berries a cold winter follows. This is obviously not through some predictive ability of the plants, but rather evidence for the fact that, generally speaking, the weather conditions which promote berry growth tend to evolve into the conditions which produce a cold winter. It obviously doesn't always pan out that way, but it often does - perhaps moreso in the past than now, but frequently enough that the old wives' tale developed.)

CB

[Gray-Wolf]

It's also the 'meeting' of compatible species that have been 'separated' by the 'old perennial' that are now in contact and interbreeding?

We also have our Whale off Israel as another indicator of conditions changing. Had we not driven our Atlantic population of Grey whales into extinction several hundred years ago we'd be able to gauge better how long it was since the two species were 'linked' (before panama lifted out of the sea blocking the Atlantic/Pacific 'join' and forcing the evolution of the N.A.D?).

I think we'd all agree that 'evolution' is an ongoing process but ,yet again, we have a number of related instances highlighting a rapid evolution of an environment being played down as 'normal' (which it most certainly is not!).

As Oz noted we have plenty of critters that are adapted to winter white but very few that are 'white' year round suggesting a positive advantage in that configuration for the critter and it's 'selfish Gene'. To suggest otherwise is just a bit of naughtiness (to my mind) and not a serious observation.

The Inuit have names for both Grizzly and Polar Bear but only now are they combining the two to describe the new hybrid. For a people reliant on knowing their environment and inhabitants for day to day survival the lack of knowledge of such a beastie would ,to me, suggest that this is new for their race (as is the 'wasp' and Bee which the U.S. Health service have been advising them on as many folk show severe allergic responses to their stings having not been habitually exposed to them in the past.

I'm all for 'Devils advocate' to explore the In's and outs of a subject but ,to me, the weight of evidence (across the board) that the recent reduction in perennial ice is a 'novel' event, and not one of re-occurrence on a cyclical basis (yes, I know we have natural variability in the Arctic ,as elsewhere on the planet, but this is now beyond just 'natural' as our evidence shows us).

As an aside to all of that I see that the denialistic bloggers are now attacking the very measures they were holding up as 'proof' of global cooling just 6 weeks ago? What's up with that?

[BornFromTheVoid]

I decided to to take all the daily readings from the IJIS site and make a yearly average ice extent from 2003-2009 (the only full years of data) and see if there are any interesting results. This is what I came up with;

2009 - 10,431,152km2

2008 - 10,460,892km2

2007 - 9,965,733km2

2006 - 10,222,601km2

2005 - 10,344,239km2

2004 - 10,657,259km2

2003 - 10,839,464km2

Interesting to note that 2009 & 2008 had a higher average extent than both 2006 & 2005, before the record 2007 melt.

If I have time, and can find the info, I will try and tie in the ice extent with solar radiation levels and get a rough guide as to which years reflected the most light.

(There are a good few days in the daily data in some of the years where no accurate ice info could be gotten and -99999 is placed instead. For these I made up readings based on the trend of the figures before and after the gaps in data).