Arctic Ice 2009

[Thundery wintry showers]

Aye, it's still very annoying that some sceptics insist that if something appears that supports AGW it is prone to uncertainty yet if it doesn't support AGW then it is automatically stonewall fact, "no ifs and buts". There is, indeed, plenty of evidence to suggest that the current ice extent is the lowest for a lot longer than 30 years. True, the current set of ice records only goes back to 1979, but they are not the only proxy available for determining ice extent.

But at the same time there are huge caveats associated with blaming the recent melt on AGW (as so many sources do) as natural factors have almost certainly made a large contribution and there's always the question of how much of the recent global warming was anthropogenic in origin. Cyclical trends indicate that the Arctic was in a warm phase between 1930 and 1960, a cool phase between 1960 and 1990 and then recently went back into a warm phase.

It would be interesting to see how much melt there was during the warm phase of 1930-1960. However, Arctic sea ice extent was clearly well advanced to the north of the UK during those cold, snowy northerly-dominated winters of 1967/68 through to 1969/70, and it mustn't have been too shabby in 1955 given the potency of that winter's northerlies.

[doctormog]

An interesting, or maybe not so interesting fact.

The date of the first gain in sea ice(which is not the date that it reached it's lowest), but is the date where synoptics become all in important.

Are as follows.

2004 2nd Sept

2005 1st Sept

2006 23rd Aug

2007 31st Aug

2008 2nd Sept

So we should very soon see our first gain.

Good (and helpful) post thanks.

Just so I can keep an eye on this, which data set have you used for this? (IJIS or NSIDC?)

[Devonian]

Just checking out Cryosphere Today it looks to me like the NE Passage is open and the NW Passage very nearly so.

[Gray-Wolf]

Just checking out Cryosphere Today it looks to me like the NE Passage is open and the NW Passage very nearly so.

Hi Dev!

Things are panning out much as predicted last year (in so far as the passages are concerned) and the folk who wish to use an ice free NW passage will need to wait a couple of years as the ice from the remnant perennial and the lost shelfs ablates or is flushed out into the Atlantic.

Anyone watching the freeing up of the passage this year will have watched last years 'chunks' sat proud as the ice around melted. These log jammed remnants will take the couple of years (that NSIDC predicted last autumn) to melt out before we can confidently predict the 6 week window of ice free passage through the Archipelago that many carriers are looking for.

I am surprised at the slowdown of the melt through July and Aug but it just goes to show that when 'natural cycles' are at their peak they still influence. I do not see this changing the predicted loss of Arctic sea ice cover.

If we suffer another 'natural cycle augmented' warm year in the Arctic losses will far exceed the stall we have encountered during this cold phase and we will see the loss of the last of the perennial ice.

[stewfox]

If we suffer another 'natural cycle augmented' warm year in the Arctic losses will far exceed the stall we have encountered during this cold phase and we will see the loss of the last of the perennial ice.

This site suggess the minimum sea ice extent upto the 1950s was cira 11 million kms2. Cira 5.5 million km2 to 6 million km2 more recently.

http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/seasonal.extent.1900-2007.jpg

How much credence do people give these figures ?

[WindWatcher]

I am surprised at the slowdown of the melt through July and Aug but it just goes to show that when 'natural cycles' are at their peak they still influence. I do not see this changing the predicted loss of Arctic sea ice cover.

If we suffer another 'natural cycle augmented' warm year in the Arctic losses will far exceed the stall we have encountered during this cold phase and we will see the loss of the last of the perennial ice.

Hi GW,

What natural cycle cold phase are we at the peak of?

Thanks

[J10]

Interesting article re Ice free NW passage from NSIDC

http://nsidc.org/arcticseaicenews/

The Northwest Passage and Northern Sea Route

So far this year, neither the Northwest Passage nor the Northern Sea Route has opened. The Northern Sea Route appears likely to open soon, but ice still clogs many of the channels in the Northwest Passage.

Whether or not the navigational passages through the Arctic Ocean will open in a given summer depends on atmospheric circulation and ice thickness. For example, although 2007 was a record low extent in the Arctic and the Northwest Passage was nearly completely open, the Northern Sea Route was still choked with ice because of a circulation pattern that pushed a tongue of ice against the Siberian coast. Recent research by Stephen Howell at the University of Waterloo in Canada shows that whether the Northwest Passage clears depends less on how much melt occurs, and more on whether multi-year sea ice is pushed into the channels. Counterintuitively, as the ice cover thins, ice may flow more easily into the channels, preventing the Northwest Passage from regularly opening in coming decades.

[J10]

We are currently around 865,000 above 2007, 260,500 above 2008, 85,000 below 2005, 43,000sqkm below 2003-08 average, and 245,000 below 2006

On the IJIS figures, the rate of ice loss stays around 55,000sqkm per day over the past week, this rate of ice loss is very slightly above average for the time of year, we are the 5th highest in the 2003-2008 range, above 2007 and 2008, below 2003-2006.

Of course remembering that the 2003-08 average is well below 30 yr averages.

Past finishes

 6032031  5784688  5315156  5781719  4254531  4707813

18/09/03 11/09/04 22/09/05 14/09/06 24/09/07 09/09/08

We are now below the final figure in 2003, and fast approaching the final figures in 2004 and 2006, it currently seems likely we will finish between the 2005 figure of 5.3m and the 2008 figure of 4.7m

With signs that 5.0m seems around the likely finish point.

I will do a midweek update on Wednesday.

5,627,656 is the Current ice extent

We are now below the low point of both 2004 and 2006.

We are now 320,000 above 2008, and 780,000 above 2007, and 225,000 below 2005, so finishing between 2005 and 2008 seems more likely, but where exactly?

We are currently around 875,000 above 2007, 423,500 above 2008, 190,000 below 2005, 75,000sqkm below 2003-08 average.

On the IJIS figures, the rate of ice loss has fallen back to around 40,000sqkm per day over the past week, and this is dropping towards the end of the week, this rate of ice loss is very slightly above average for the time of year, we are set to finish above 2007 and 2008 and below all previous years.

Of course remembering that the 2003-08 average is well below 30 yr averages.

The Current Ice Extent is 5,539,531

Remaining Year End Figures

2005 = 5,315,156

2007 = 4,254,531

2008 = 4,707,813

2003-2008 Average = 5,312,656

Again a figure of around 5.0m seems likely, but can we finish above this.

[Gray-Wolf]

Thanks for that J1! and a big thanks for all your efforts over the season, it's nice to have someone able to put up the weekly figures without any great personal interpretation on them as you do so (I know I'd be hard pushed to do that bit!).

I must admit that I am pleasantly surprised at the way we have maintained extent this year (long may it continue!) and can only hope that the conditions in the Arctic also enabled the perennial to fare as well.

I'm interested in how the 'Arctic Amplification' appears this year as you'd imagine it's impact also lessened which should mean an earlier ice build than of recent years which should help plump up the final figures come March (had we not been so slow in ice build these last couple of years we may well have seen final extent figure approaching the 30 yr average?)

I hear (from other sites) that above 75N we are already into the 're-freeze' so the final phase of the melt (when losses to the south are balanced out by gains to the north) seem to be beginning.

[stewfox]

I hear (from other sites) that above 75N we are already into the 're-freeze' so the final phase of the melt (when losses to the south are balanced out by gains to the north) seem to be beginning.

Which makes it another remarkable year of recovery

Has the single year ice lasted longer then expected ?

If thats true the artic has a capacity to bounce back , not seen by some. I appreciate we would need to see several more years of 'recovery'.

[Iceberg]

I still think we need to hang on a bit, there is still a possible 3-4 weeks of melt left, we are still going down and haven't recorded an increase in ice, if we don't do this in the next couple of days, this will be the latest for quite some time.

[J10]

Midweek update, it is true that we have yet to see a daily rise, but the trend is still for small falls at the moment, of around 30,000sqkm per day.

The current ice extent is 5,423,750 around 111,000 below 2003-09 average, we are 225,000 below 2005, but 465,000 above 2008 and 810,000 above 2007.

Between 2005 and 2008 seems increasingly likely, can we stay above 5,000,000sq km?

Latest update spreadsheet attached, after this was missed off for Sunday.

[Iceberg]

Yep completely agree with all of that Jackone,

Another 30K fall today and we officially have the latest first rise in ice of the year using the IJIS dataset(it must happen soon).

2008 had quite an early minimum for recent times looking at say 2005 this was much later around the 22nd of September, so a very possible 19 days of melt left making the 5M mark an interesting target, I am not sure we'll reach it now, which is a very good thing.

The next figure to reach is 5315156 which is the 3rd lowest min recorded.

[doctormog]

Yep completely agree with all of that Jackone,

Another 30K fall today and we officially have the latest first rise in ice of the year using the IJIS dataset(it must happen soon).

Not that it's really of any significance but a few points, the drop yesterday (today's data aren't available yet) was just over 25000. The data for the 3rd September could theoretically show an increase I suppose. Also, when was the "first rise in ice of the year" in 2003?

[Mr Maunder]

Not that it's really of any significance but a few points, the drop yesterday (today's data aren't available yet) was just over 25000. The data for the 3rd September could theoretically show an increase I suppose. Also, when was the "first rise in ice of the year" in 2003?

12th September showed the "first rise in ice" in 2003.

MM

[J10]

What is surprising me at the moment, is the consistent level of the falls, around the 20,000 mostly with the odd 40,000 over the past week.

On top of the 2005 figure above other figures of note are 5,312,656 (the 2003-08 average), 5,254,531 which would be 1m above 2007 and 5,207,813 which would be 500k above last year.

Given the rate of loss ranges from 95k (2004) to 363k (2007) with an average loss of 235k From 2nd Sept to minimum ice extent, then a figure of 5.15-5.20m is most likely but hopefully the ice will remain above the markers laid out.

Next update on Sunday, hopefully the first rise will happen before then.

[MR EXTREMES]

this dont sound good,

http://news.bbc.co.uk/1/hi/sci/tech/8236797.stm

[stewfox]

this dont sound good,

http://news.bbc.co.u...ech/8236797.stm

Dont worry im sure its from April 1st

Its total tosh, i like this

"Scientists have been accused for years of scaremongering. But the real scaremongers "

Lest all go back and have barbeques in Greenland then

Anyway back to reality ice seems to be holding up nicely another year of recovery

[Thundery wintry showers]

It's a thorough piecce of research and not "tosh" at all. Studies of ice core data gives approximate indicators of what Arctic temperatures were like centuries ago.

However, that doesn't make it definitely right- someone could come up with something else that challenges this study's findings in the future (for instance changes in the extent of the bulges of the Medieval Warm Period).

Looking at the Arctic temperatures, they look like staying fairly steady for another five days or so, before declining afterwards, though we can't always trust the GFS at this range. Therefore if pushed I suggest that the ice may continue to slowly recede up to Sunday but probably start its recovery next week.

[MR EXTREMES]

Dont worry im sure its from April 1st

Its total tosh, i like this

"Scientists have been accused for years of scaremongering. But the real scaremongers "

Lest all go back and have barbeques in Greenland then

Anyway back to reality ice seems to be holding up nicely another year of recovery

i agree it is holding up yes theres plenty of bits of this story i picked out and id say rather odd story.

[stewfox]

It's a thorough piecce of research and not "tosh" at all. Studies of ice core data gives approximate indicators of what Arctic temperatures were like centuries ago.

However, that doesn't make it definitely right- someone could come up with something else that challenges this study's findings in the future (for instance changes in the extent of the bulges of the Medieval Warm Period).

Looking at the Arctic temperatures, they look like staying fairly steady for another five days or so, before declining afterwards, though we can't always trust the GFS at this range. Therefore if pushed I suggest that the ice may continue to slowly recede up to Sunday but probably start its recovery next week.

I apologise the word 'tosh' is not the appropriate word. Its the 'spin'.

An analogy would be when Man Utd lost to Burnley it meant they were doom to go down.

The 'spin' put on these things tends to ruin any useful underlying data we see it time and time again.

ps I bet heavy snow will effect those attending UN climate summit in Copenhagen in December.

[Solar Cycles]

It's a thorough piecce of research and not "tosh" at all. Studies of ice core data gives approximate indicators of what Arctic temperatures were like centuries ago.

However, that doesn't make it definitely right- someone could come up with something else that challenges this study's findings in the future (for instance changes in the extent of the bulges of the Medieval Warm Period).

Looking at the Arctic temperatures, they look like staying fairly steady for another five days or so, before declining afterwards, though we can't always trust the GFS at this range. Therefore if pushed I suggest that the ice may continue to slowly recede up to Sunday but probably start its recovery next week.

Ice core data is not an accurate assessment of past temperatures. And running computer models backwards, with flawed data, will only give you flawed results!

[Gray-Wolf]

I would find it a tad strange if instead of our current 'warming' merely offsetting the current northern hemisphere 'cool phase' it had been responsible for reversing the impacts of our orbital 'wobble', throwing it into reverse, over the past 150yrs?..........maybe all that 'missing heat' would be accounted for then?, maybe we are spot on with our CO2 calcs but were unaware of the amount of cooling the CO2 increase had to offset before impacting temps?

[Solar Cycles]

I would find it a tad strange if instead of our current 'warming' merely offsetting the current northern hemisphere 'cool phase' it had been responsible for reversing the impacts of our orbital 'wobble', throwing it into reverse, over the past 150yrs?..........maybe all that 'missing heat' would be accounted for then?, maybe we are spot on with our CO2 calcs but were unaware of the amount of cooling the CO2 increase had to offset before impacting temps?

What current warming would that be GW? Global temps have been static for 11 years!

[Thundery wintry showers]

Ice core data is not an accurate assessment of past temperatures. And running computer models backwards, with flawed data, will only give you flawed results!

Can you provide evidence for the first part of that statement?

Although the point about computer models is certainly a good one, I don't see much relevance here either.