Arctic Ice Watch

Post by **kenneal - lagger** » 26 Jan 2016, 17:27

That's the problem with trying to look at each years weather on an individual basis, Snow. Compare individual year graphs with 30 year or more trend graphs and the picture becomes more obvious from a climate point of view.

Post by **clv101** » 26 Jan 2016, 18:42

Arctic sea ice has high interannual variability as it's strongly influenced by the weather, which as we all know is highly variable. Little can be learned about climate change or any longer trends by looking at individual years.

I'm sure everyone here is aware that Arctic and Antarctic sea ice are about as different systems as you can expect the find. One's a small ocean surrounded by land the other a small (ice sheet covered) continent surrounded by ocean. It would be odd for the two systems to respond similarly to similar forcing. One particular difference with Antarctic sea ice is that as the ice sheet melts it leaves a cool (easier to freeze), fresh (easier to freeze), light (stays on top) layer of water on the relatively warm, salty, dense ocean water. Under these conditions expanded sea ice is just what you'd expect from a melting ice sheet.

johnhemming2 · Post by **johnhemming2** » 26 Jan 2016, 19:16

Greenland was still v cold last time I looked (a couple of weeks ago).

snow hope · Post by **snow hope** » 26 Jan 2016, 23:55

clv101 wrote:Arctic sea ice has high interannual variability as it's strongly influenced by the weather, which as we all know is highly variable. Little can be learned about climate change or any longer trends by looking at individual years.

Ok, then Ralph's post is not very relevant then - agreed?

clv101 wrote:I'm sure everyone here is aware that Arctic and Antarctic sea ice are about as different systems as you can expect the find. One's a small ocean surrounded by land the other a small (ice sheet covered) continent surrounded by ocean. It would be odd for the two systems to respond similarly to similar forcing. One particular difference with Antarctic sea ice is that as the ice sheet melts it leaves a cool (easier to freeze), fresh (easier to freeze), light (stays on top) layer of water on the relatively warm, salty, dense ocean water. Under these conditions expanded sea ice is just what you'd expect from a melting ice sheet.

Ok, then if the Antarctic Sea Ice is close to a minimum this year, then that indicates the opposite if what we would expect, so that must indicate less ice sheet melting?

I think I have interpreted your post and the logic correctly.

But correct me if you have made a mistake....

Post by **clv101** » 27 Jan 2016, 00:07

snow hope wrote:Ok, then if the Antarctic Sea Ice is close to a minimum this year, then that indicates the opposite if what we would expect, so that must indicate less ice sheet melting?

I think I have interpreted your post and the logic correctly.

The process I mentioned is about ice formation, leading to maxima, not related to the summer minima which is all about melting. I don't think there's a correlation between annual maxima and minima, driven by different processes.

snow hope · Post by **snow hope** » 27 Jan 2016, 00:26

Ok, it will be interesting to see if the logic you have outlined holds. I am a computer and mathematics man - logic is everything.

Post by **kenneal - lagger** » 27 Jan 2016, 03:44

Most deniers quote the expanding winter ice extent of Antarctica when they say that the ice is getting larger despite so called global warming. This expanding ice sheet is due to the mechanism that Chris mentioned above of increasing fresh, meltwater freezing at a lower temperature.

In recent years all the talk about the summer ice in Antarctica has been about ice sheet collapse causing ice minima and deniers keep well away from that. We are approaching just such a minima now, possibly a record one, which is combining with a very low Arctic ice area to give possibly a new record ice minimum.

If you want to see which way the ice is going though, look at the graphs of the trend which are resolutely on a downward slope.

PS_RalphW · Post by **PS_RalphW** » 20 Feb 2016, 02:23

We are now approaching the arctic ice winter maximum, and it is looking like the extent and area measurements are both going to be record low levels, sharply lower than last year's record lows. Air temperatures have remained stubbornly high (if -20C is high) and the after effects of El Nino are still sending large warm weather systems into the arctic on botht eh Atlantic and Pacific sides. This is lead to much less peripheral ice, and slower growth of the central ice. Piomas model of ice volume is not at record low, because of the residual rebound in ice volume in the last 2 years.

In the last week or two, a strong high pressure system has finally set up in the central arctic, leading to a powerful Beaufort Gyre (rotation of the ice sheet about the centre of the low) leading to extensive cracking of the ice sheet and open water of the north coast of Canada and Alaska. This has happened before, and at this time of year can increase ice volume as the exposed water very rapidly freezes. However, winter solstice is long past, and the weak sun is beginning to return to the ice sheet, so soon some surface melting can begin.

Blue Peter · Post by **Blue Peter** » 22 Feb 2016, 15:08

FWIW, the website http://cci-reanalyzer.org/DailySummary/index_ds.php

shows the temperature of the Arctic 7.06 degrees centigrade above the 1979 - 2000 baseline. That is a phenomenal amount (I have never seen it more than about 3 degrees over). It is no doubt still very cold there, but if readings like that become more common during the melt season....

Peter (hoping that it's an error).

biffvernon · Post by **biffvernon** » 22 Feb 2016, 19:33

The thin blue line is certainly diverging from the grey zone.

http://nsidc.org/arcticseaicenews/

Blue Peter · Post by **Blue Peter** » 23 Feb 2016, 09:13

Blue Peter wrote:FWIW, the website http://cci-reanalyzer.org/DailySummary/index_ds.php

shows the temperature of the Arctic 7.06 degrees centigrade above the 1979 - 2000 baseline. That is a phenomenal amount (I have never seen it more than about 3 degrees over). It is no doubt still very cold there, but if readings like that become more common during the melt season....

Peter (hoping that it's an error).

Now +7.84, so presumably not an error

Peter.

biffvernon · Post by **biffvernon** » 23 Feb 2016, 12:18

Nope, no error. The South Pole is still quite cool!

PS_RalphW · Post by **PS_RalphW** » 24 Feb 2016, 11:38

Cryosat now publish ice volume measurements as an alternative to PIOMAS.

http://www.cpom.ucl.ac.uk/csopr/seaice.html

What is interesting in the current image is the large pink/read area to the north east of Greenland. This is thick, multiyear ice, and it appears poised to drift south into the Fram straight, where it will almost certainly melt out this spring. This thickness distribution map is noticeably different from the PIOMAS model. If it is correct, it is another indicator that 2016 could be another year of record low Arctic ice.

PS_RalphW · Post by **PS_RalphW** » 09 Mar 2016, 12:51

Very symbolic

http://neven1.typepad.com/blog/2016/03/ ... e-ice.html

Colder weather on the Pacific side of the Arctic has allowed ice extent to exceed last year's record low maximum by the tiniest fraction of the measurement uncertainty. Sea ice area still on track for record low maximum.

the latest PIOMAS update puts ice volume back to second lowest on record, just behind 2011. This is the sharp relative decline I have been expecting from the record warm Arctic winter, and is yet another domino lined up for a record melt season ahead.

emordnilap · Post by **emordnilap** » 16 Mar 2016, 12:11

PS_RalphW wrote:Very symbolic

http://neven1.typepad.com/blog/2016/03/ ... e-ice.html

Colder weather on the Pacific side of the Arctic has allowed ice extent to exceed last year's record low maximum by the tiniest fraction of the measurement uncertainty. Sea ice area still on track for record low maximum.

the latest PIOMAS update puts ice volume back to second lowest on record, just behind 2011. This is the sharp relative decline I have been expecting from the record warm Arctic winter, and is yet another domino lined up for a record melt season ahead.

Another irony is the number of snowmobile users being lost by drowning because of climate change.