280 replies to this topic

[Gray-Wolf]

http://nsidc.org/arcticseaicenews/

Looks like NSIDC confirm my fears of what is happening down Fram. With any continued phase of Atlantic blocking comes the probability that the rest of the 'older ice' ,behind Greenland and out to the archipelago, will follow suit over the next 3 months.

I also note that the areas I have concerns over have been highlighted in the report with the prospect of 'rapid melt' from here on in.

Expect that extent line to now start to really plummet and the folk who "whoopee do'ed" about the 'anomalous high' extent through March to now repeat (mantra like) that "it is summer, what do you expect?" at any mention of ice extent......lol!

EDIT: After a quick look at yesterdays MODIS images it is easy to see the breakup around the north of Greenland and the 'clear water' around it's coast. For those who knew the ice back in the late 90's you'll know how unusual both the 'clear water' and this level of fragmentation is. Back in those days the strip from north of Svalbard through to the Archipelago was solid perennial and the ice that moved was restricted to a circulation north of this mass. If this mass is now 'free' it will join with this circulation and the line of older ice it contains will be brought in front of the Arctic current that feeds Fram. With the Atlantic blocking 'ongoing' it appears likely that all of this ice will be drifted into the north Atlantic over summer allowing an expanse of 'open water' to the North of Greenland. This is important for 2 reasons;

1/ The ocean will mix out it's stratification (as on the Siberian side) making it unlikely for it to maintain ice cover over summer in the future (no depth of ice can form with the warmer waters at the surface).

2/ the impacts of 'open water' can be measured 1,500km inland so the north of Greenland's ice sheet will be further impacted. Last year we had data showing that the ice there was now melting as fast as the rest of Greenland and I have to wonder whether the collapse of the 'old perennial' (as Dr B. saw) allowed mixing in this ocean area over the past 2 years allowing for this years unprecedented melt out?

http://rapidfire.sci....php?T101241835

If you 'zoom' the above to 250m you'll then (if you press on your mouse wheel you can 'fly' over the image) be able to see the ice I'm on about. At the left is the northern end of Nares with it's concave collapse and at the right is Fram, you can see the way the ice is tending and also how empty Fram is becoming as the ice there melts out before flowing south.

For those interested;

http://rapidfire.sci....php?T101241835

Check out the images from Svalbard through to Frans Ferdinand and see how the 'older ice' here is doing.

Edited by Gray-Wolf, 05 May 2010 - 08:26 .

[Captain_Bobski]

Gray-Wolf, on 26 April 2010 - 09:03 , said:

A warm summer this year with favourable currents/winds and we will reach this 1 million km mark. If not we will still challenge the 07' 'record' even without 'exceptional circumstances' up there.

Was the extent of blocking over the Winter not "exceptional" then?

CB

[Gray-Wolf]

I find it so but , if you recall, the circumstances that were found responsible for 07's melt did not involve Atlantic blocking but an Arctic H.P. which kept skies clear and the winds circulating the central pack.

The current 'setup' (low solar driven???) lends itself to both the import of warm air across much of the Arctic and also accelerating the flow out of the Arctic via both Fram and Nares. As we have all seen the past 2 years has concentrated the old ice in a ribbon from the Archipelago to Fram. My concerns are the loss of this ice ,over a single season, due to melt and transportation out of the high Arctic.

As you know I saw no recovery over the past 2 years just a continued degradation of the perennial we still held. This year will now remove those fragments and allow us a clearer picture of the situation there. We should also be getting good data from IceBridge and Cryosat2 by July and so will have the info on the 'depth' of this older ice as it shifts East, I would not be surprised to find it 'unlike' our understanding of perennial as we knew it and to comprise of 2 to 3m thick floes with single year matrix (hence it's readiness to shatter).

As an aside I would also not be surprised to see 'extent' drop below most other plots in the next 2 weeks as the new ice melts in the central area and continues to be lost in Bering, Fram and Baffin/Davis

EDIT; Sea ice volume plots showing no recovery in ice amounts since 07's 'anomalous melt'

http://psc.apl.washi...malyCurrent.png

http://psc.apl.washi...e/IceVolume.php

even with it's extent supposedly so good 2010 seems (to me) to have a similar volume (before melt season proper) as 07'???

Edited by Gray-Wolf, 05 May 2010 - 09:05 .

[BornFromTheVoid]

Gray-Wolf, on 05 May 2010 - 07:39 , said:

http://nsidc.org/arcticseaicenews/

Looks like NSIDC confirm my fears of what is happening down Fram. With any continued phase of Atlantic blocking comes the probability that the rest of the 'older ice' ,behind Greenland and out to the archipelago, will follow suit over the next 3 months.

I also note that the areas I have concerns over have been highlighted in the report with the prospect of 'rapid melt' from here on in.

Expect that extent line to now start to really plummet and the folk who "whoopee do'ed" about the 'anomalous high' extent through March to now repeat (mantra like) that "it is summer, what do you expect?" at any mention of ice extent......lol!

Just with regards the NSIDC article, why are the temperature anomalies for the Arctic just shown for the 925hPa level and what's the average they compare with?

[Gray-Wolf]

NaDamantaSam, on 05 May 2010 - 11:12 , said:

Just with regards the NSIDC article, why are the temperature anomalies for the Arctic just shown for the 925hPa level and what's the average they compare with?

I'd ask them direct! they (I have found) are very approachable and happy to help with your queries.

Off the top of my head I'd think you'd want to measure 'air temps' above the layer directly atop of the ice as this would give a false reading (I've always had a thing about 2m temps when the water below the ice is obviously 'positive' otherwise it wouldn't be water would it??? so maybe they have a thing about 2m temps too!!!)

[Captain_Bobski]

Gray-Wolf, on 05 May 2010 - 08:46 , said:

I find it so but , if you recall, the circumstances that were found responsible for 07's melt did not involve Atlantic blocking but an Arctic H.P. which kept skies clear and the winds circulating the central pack.

So?

What difference does it make if the exceptional circumstances are different? They're still exceptional.

You just can't accept it unless it's all our fault, can you GW?

CB

[Gray-Wolf]

Captain_Bobski, on 05 May 2010 - 16:51 , said:

So?

What difference does it make if the exceptional circumstances are different? They're still exceptional.

You just can't accept it unless it's all our fault, can you GW?

CB

C-Bob , you're a family man ,you know it's always "your own fault....."

If the low solar leads to more settled conditions here on earth (as I was taught back in the 80's) then the Atlantic blocking, during low solar, is to be expected is it not? We've been stuck with it for a while now!!!

Sadly , when you look at the charts, this blocking may well bring cold plunges across us whilst we're hoping for a little warmth to appear but how far north do those plunges originate?

You can basically see the whole of Fram in this flow of air driving the ice south (down the East coast of Greenland).

It is an unfortunate happenstance that the lowest volume of ice we have ever measured AND the oldest ice being lined up behind Fram occurs with such a synoptic in place.

Anyhow, if I do have a persecution complex I probably did something to deserve it..........

[stewfox]

Gray-Wolf, on 05 May 2010 - 18:05 , said:

Anyhow, if I do have a persecution complex I probably did something to deserve it..........

Are we now in free fall as GW predicted, are we due to eat large dollops of humble pie

http://www.ijis.iarc...aice_extent.htm

[Gray-Wolf]

stewfox, on 06 May 2010 - 13:48 , said:

Are we now in free fall as GW predicted, are we due to eat large dollops of humble pie

http://www.ijis.iarc...aice_extent.htm

Ooooh, I don't like 'predict', I kinda see it as an obvious outcome from the volume of ice we have and it's current 'extent'. We still have lots of melting ice from the 'late spurt' outside of the Arctic to melt out (rapid melt there) and then the thin ice in the areas that had a warm winter (Canadian basin, Barents, central pack) but we also need to watch our weather as this Atlantic blocking places the northerlies we receive right over the Fram straight and so may ship more ice out than normally at this time of year further accelerating loss.

The real test comes in late July and through Aug as this used to be the time that the melt started to slow as the melt eat back into the older ,thicker ice. If we have no 'Thicker ice' then the melt will tend to continue unhindered.

Another point to note is the amount of 'early' spaces in the arctic ocean and the 'early' warming this will allow for the exposed waters. this may also accelerate the melt of any surviving ice that drifts over such regions.

As I've said it's not a 'prediction' but more a 'logical projection' of what we have there at the moment.

[Gray-Wolf]

I . for one ,miss J1's inputs on this thread so to try and abridge that absence the next 4 months will see ice levels drop below all others and then ,come winter , a freeze will set in.......

[Snow White]

stewfox, on 06 May 2010 - 13:48 , said:

Are we now in free fall as GW predicted, are we due to eat large dollops of humble pie

http://www.ijis.iarc...aice_extent.htm

The rate of decline after early to mid June is when we really need to start watching closely. Its far to early to predict any outcomes yet unless your GW.

[Gray-Wolf]

Just to repeat. There is 'no' prediction ,just a projection of what occurs when you spread 07's ice mass over 2010's sea ice extent......how could you even hope for any better than that?

Over 3 days we have fallen from highest extent in the IJIS series to mid pack. By June we are scheduled to be the lowest in the series and, as S.W. observes, thereafter is the test of the durability of the Arctic ice.

[cooling climate]

Snow White, on 07 May 2010 - 00:10 , said:

The rate of decline after early to mid June is when we really need to start watching closely. Its far to early to predict any outcomes yet unless your GW.

Your quite right of course, leave the alarmist nonsense to GW and his followers. If the summer produces a very negative
AO then you would expect to see more melt in the Arctic during the summer regardless of what happened in 2007
but even then we will still not see any where near the melt that occurred in 2007.

[stewfox]

cooling climate, on 07 May 2010 - 07:45 , said:

but even then we will still not see any where near the melt that occurred in 2007.

Based on ?

I don't know what's worse alarmist nonsense or just 'because it wont happen'.

3^rd week of June is when things 'may start to happen'.

No one knows how the arctic ice will look by September 2010

[BornFromTheVoid]

As of the 6th May, 2010 stands at 3rd highest extent out of the last 8 years and 194,140km2 above the 8 year average. We are now 266,250km2 behind 2009, 36,719km2 behind 2008 and also 104,375km2 ahead of 2003 and 682,969km2 ahead of 2006.
We are running at the second highest rate of melt over the last 10 days (Apr 26 - May 6) with an average of 72,875km2/day. The 8 year average is 48,832km2/day, the highest rate is 2006 at 76,453km2/day (less than 4k more than 2010) and the lowest is 2008 at 17,609km2/day.
Arctic ice not looking great at the moment, of course things can change though. By tomorrow, bar a sudden slowdown, we will probably have the highest 10 day rate of melt in the series. A relatively mild Arctic winter, atop the ice still struggling to recover after 2007 leaves myself at least with the feeling the we need something special to avoid a very low extent come September.

[Gray-Wolf]

I'm still struggling with the notion that we already have 'less ice' than at the 07' min.

If volumes are so low yet extent spread that volume across the whole Arctic basin (and outside) then I'm struggling to find any way of protecting that ice from the waters below and the 24hr days of solstice (and a potential of 12.64w per m2).

We should know by that time (solstice) what we can expect from the rest of the melt season (I figure) as we will see lots of ice in the central pack melting back from the winters frozen over leads. If the ice is very thin then it will fragment quite readily as wind blows floe into floe. With even more surface area exposed to atmosphere and ocean the ice will surely melt out? Once this phase is over it will be up to the ice itself (thickness) and the weather up there (sunny or not and wind direction/strength).

What I feel we don't need is any continuation of our 'blocked Atlantic' as this is feeding warm air in over Canada and flushing cold air down the Fram straights blowing the ice train with it.

[songster]

Gray-Wolf, on 07 May 2010 - 11:59 , said:

I'm still struggling with the notion that we already have 'less ice' than at the 07' min.

You're reading the graph wrong. It's not a measure of absolute volume, it's a measure of the volume anomaly, i.e. how much more/less ice there is than average for the time of year. In September 2007, there was about 8000 km3 less ice than the September average. Currently, we have about 8000 km3 less than the May average.

[Gray-Wolf]

That would explain it!!! Silly me....

[Gray-Wolf]

IJIS plot is still on the ski slope downwards. Amazing (or not) what a week can bring to 'extent' figures isn't it?

The last echo's of 'record extent' are still ringing in our ears and here we are mid-table all of a sudden!

Didn't some-one forewarn us all that this looked the most probable outcome for the spring phase of this years melt (once you looked at the conditions on the ground and projected the 'normal progression' onto these observations)?

I'm sure that soul will be back 'projecting' come late June when the summer melt begins in earnest!

[BornFromTheVoid]

Gray-Wolf, on 12 May 2010 - 09:24 , said:

IJIS plot is still on the ski slope downwards. Amazing (or not) what a week can bring to 'extent' figures isn't it?

The last echo's of 'record extent' are still ringing in our ears and here we are mid-table all of a sudden!

Didn't some-one forewarn us all that this looked the most probable outcome for the spring phase of this years melt (once you looked at the conditions on the ground and projected the 'normal progression' onto these observations)?

I'm sure that soul will be back 'projecting' come late June when the summer melt begins in earnest!

Yup, things looking much worse as this free fall continues. If this rate of ice loss continues for just another 10 days we will be at the lowest in the series.

The areas responsible for the sudden fall are Bering Sea, which is still above average but has lost about 400,000km2 in the last month, the good thing is it's usually ice free by the beginning of June so won't be contributing the the free fall then. Okhotsk sea ice is in a very similar situation, having lost about 400,000km2 in the last month but by June will have hardly any ice left anyway.
The last main contributor has been the Barents ice which has lost almost 500,000km2 in a month but still has another 2 months melt to go!

Those 3 areas always lose their sea ice though so don't really contribute towards the overall eventual minimum extent so in that sense we still can hope that the main central ice and the Canadian archipelago can hold up a little better rather than continuing on the "ski slope".