Arctic Ice 2009

[Admiral_Bobski]

If you were a bookie, what odds would you offer, based on the trends and the summary, on there being more sea ice in September 2019 than there is this year? Ands what would the odds be on there being less?

And that's precisely the reason I don't go to the bookie's...

CB

Edited September 19, 2009 by Captain_Bobski

[parmenides3]

Me neither. LOL P

[doctormog]

Hi Doc.,

When you refer to the starting baseline, are you suggesting that there will be more ice, or more second-year ice? I agree (it is self-evident) that if next year is like this year, we'll have a similar amount of ice at the end of the Summer.

So far, I haven't said this is not a recovery, but I will now. Repeating what has been said many times before, the thing that matters is the trend. If we continue along the trend line, in 2019 we'll have another drop of 8.7% of levels. To suggest that this is a recovery is like suggesting that losing a football match 6-0 the week after losing one 8-0 is a recovery. It's optimistic.

Last thought; most Cryosphere specialists do not expect sea ice levels to return to the long-term average for a long time; they expect the trend to continue. They are concerned that, as the trend continues, we will reach a point where the equilibrium has been so unbalanced that recovery won't happen for thousands of years (OTBE). Some think this point has already been reached; some think it is close and will inveitably be reached, some aren't convinced yet that the cryosphere cannot recover at some point.

If you were a bookie, what odds would you offer, based on the trends and the summary, on there being more sea ice in September 2019 than there is this year? Ands what would the odds be on there being less?

The point I was making, and that your post reinforces, is that future predictions are largely based on this trend to which you refer. Are you very confident this trend will continue as it has done for the next 10 years? If so, what is that high confidence based upon? hat's my point not about the past but the fact it is being largely used as the sdole predictor for the future.

As I said above their are too many unknowns for me to say what the picture will be like in a year never mind ten years!

[laserguy]

Are you very confident this trend will continue as it has done for the next 10 years?

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

Although in it's infancy,there's only one trend in evidence here,and it ain't what the AGW types and the media would have the great unwashed believe. And look at the rate of recovery over the last two years compared to it's stately decline. As you point out dm,who can say how long the current trend will persist for? But if I was a betting man and the bookies offered odds on such matters,I know which scenario/outcome I'd be putting my shirt on! 'AGW' continues to hang on by the skin of it's teeth... soon be game over.

[Admiral_Bobski]

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

Although in it's infancy,there's only one trend in evidence here,and it ain't what the AGW types and the media would have the great unwashed believe. And look at the rate of recovery over the last two years compared to it's stately decline. As you point out dm,who can say how long the current trend will persist for? But if I was a betting man and the bookies offered odds on such matters,I know which scenario/outcome I'd be putting my shirt on! 'AGW' continues to hang on by the skin of it's teeth... soon be game over.

As I said earlier on, I wouldn't be willing to put money on either outcome, the reason being that I don't believe we know enough about the situation to be able to determine the odds of those outcomes.

I would describe myself as a relatively ardent skeptic, because I have what I think are good scientific reasons for being skeptical of the accepted description of AGW. (I may, of course, be wrong and my scientific reasoning is complete bobbins, but that's just the way it is.) However, I also like to think that I'm open-minded, and if my scientific reasoning is shown to be wrong then I will happily alter my views. In fact I have done that several times over the last couple of years because of discussions on these boards.

Still, despite my "Ardent" status, I still wouldn't bet on cooling to happen at this point. Purely natural, yet unanticipated, factors may yet make it warm further.

I also think that AGW is "hanging on" by rather more than the skin of its teeth. It's a well-founded hypothesis which is well-accepted (not universally accepted, and there's far more debate going on than some Pros would have you believe).

"Game Over" will come one of two ways - either some piece(s) of science will come along which will prove AGW wrong, or else it will wither and die very slowly.

I think that, barring a masterful work of scientific reasoning, AGW (as a concept) will be with us for a very long time to come. I'm hopeful of that masterpiece coming along soon, one way or another, but I'm certainly not going to be holding my breath for the death of AGW.

CB

[beng]

Last thought; most Cryosphere specialists do not expect sea ice levels to return to the long-term average for a long time; they expect the trend to continue. They are concerned that, as the trend continues, we will reach a point where the equilibrium has been so unbalanced that recovery won't happen for thousands of years (OTBE). Some think this point has already been reached; some think it is close and will inveitably be reached, some aren't convinced yet that the cryosphere cannot recover at some point.

I think they would have more credibility in their long term predictions if they had managed to predict the extent for the last 2 seasons a bit better. Time will tell either way I guess.

[Gray-Wolf]

though maybe a tad pedantic you may need to factor in the 'start points' when you look at ice gains L.G. Of course I haven't but I do recall the same guys calling for a recovery trend also pointing out ice levels at ice max over the past 2 years. I would think if you took one away from the other (max minus min kinda thing) would we not find the amount of ice melted each season?

If we then compared this with other years we might not find any convincing gains over summer but increases over winter only (weather as opposed to climate again)

[MR EXTREMES]

we will have to wait and see what happens.

but its a start so no doom and gloom to report on gray wolf.

Edited September 20, 2009 by badboy657

[parmenides3]

I think they would have more credibility in their long term predictions if they had managed to predict the extent for the last 2 seasons a bit better. Time will tell either way I guess.

Beng; there is a lot of blog action going on these days discussing the likely numbers, including a number of gambles. This is partly because opinions even among specialists vary, but mainly because the Cryosphere, particularly the Arctic, is so strongly affected by natural variability that any one season's metrics are almost impossible to anticipate. So the discussions are about the likelihoods, and the significance of events like 2005 and 2007.

You seem to be making the classic mistake of thinking of a climate trend as a linear progression, and seeing a short-term reversal of that trend as significant, whereas it is not a linear progression, and the significance of short-term results is effectively zero, unless they happen to fall into the category of 'unprecedented', in which case, their significance needs to be considered.

Time has told. there is 25% less sea ice in the Arctic this Summer than there was, on average, between 1979-2000. I encourage you and everyone to consider not the moment, but the pattern, the trend; in climate terms, this is what matters. I would say the same if the ice extent had been a new record low this year.

Look at the trend. How much ice is there likely to be in 20 years time, compared to 1979-2000?

P

[Gray-Wolf]

Hi P3!

I don't think we can remove the humanity from any discussion that involves change that is unwelcome. Anyone watching a relative fade away knows how easy it is to gain hope from slight improvements when they are set against a steady decline.It is human nature to do just this.

My concerns are more that beyond a certain point the problem becomes less tied in with the fickle nature of climate drivers (or seasonal weather) and change just fuels itself.

I'm sure if we looked for similar summers to the past 2 in the Arctic and looked at the levels of ice retention in those years we'd be asking ourselves why the past two years faired so poorly (from 'average' start points that closely match the rolling average).

As I mentioned further up the thread to see that from start points in line with the 30yr rolling average we still end up with the ice over 30% less than in the past come ice min is very worrying.

We have to pray the the 'coolists' have it spot on and we can enjoy 20 yrs of continuous ice rebuild for any repeat of the 05'/07' losses will cost us the remnant pack (IMHO) and we then face the greater impacts that this will have on the global climate system.

[Admiral_Bobski]

I'm sure if we looked for similar summers to the past 2 in the Arctic and looked at the levels of ice retention in those years we'd be asking ourselves why the past two years faired so poorly (from 'average' start points that closely match the rolling average).

But GW, it was you yourself who pointed out that ice volume at the start of these past two summers has been lower than any time in the instrumental record.

So there's your answer - the past 2 years have faired so poorly because, despite relatively good ice extent, the ice volume was lower than any other comparable years.

Considering the ice volume was lower at the start of both the 2008 and 2009 seasons than it was at the start of the 2007 season, the pack has held up remarkably well.

CB

[Gray-Wolf]

Yup C.B. ! therein lies the problem. As P3 points out we need to look at the overall trend in ice (volume and extent) but we must wait until October when those figures become available to see just how things went over this summer.

Whilst we're discussing overall trends we need to look at the outflow from Greenland over summer too as last year had the north coast of Greenland suffering the greatest mass losses. As many point out the loss of all the floating pack won't instantly alter climate but the rapid loss of part of Greenland's ice sheet would leave many coastal areas with immediate concerns.

If the recent increases in 'dark water ' across the Arctic over the summer months proves to be one of the factors fuelling ice loss in Greenland then we should be hoping for a continued increase in ice extents ( so as to restrict the input of solar energy there over the summer months) but this will not occur without a thickening of the existing ice to make it more durable.

As I understand things the ICESAT mission showed us that we still see ice thinning of the pack over the winter months at the moment meaning that the second and third year ice no longer indicates a certain thickness/durability.

We also saw the continued loss of the remaining 'old perennial' into the Atlantic into December last year and so we need be mindful that ice mobility, coupled with the positioning of the remnants of the 'old perennial', has it at risk of transport out of the arctic throughout the winter and summer.

To say "look, we have more perennial because we held onto more ice this summer" no longer seems to be enough.Until we can see thick, old ice rebuilding we face an uncertain future in the arctic with the prospects that one 'warm summer' will be capable of wiping out all the recent gains over a period of a few months.

[stewfox]

It would appear that at present the ice is increasing at a faster rate then other year this century apart from 2002 (for this time frame)

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

It would be nice to see 15sqkm2 by early March next year

[SteveB]

This is an interesting chart.

Not sure why though the average & 2008 dip going into October though?

http://nsidc.org/dat..._timeseries.png

Edited September 22, 2009 by SteveB

[Nick L]

This is an interesting chart.

Not sure why though the average & 2008 dip going into October though?

http://nsidc.org/dat..._timeseries.png

Because that's the Antarctic, October is mid-Spring down there!

[BLAST FROM THE PAST]

Because that's the Antarctic, October is mid-Spring down there!

LOL!

This is interesting

With warmest EVER oceans ice is recovering...let's have even warmer oceans then shall we? :blink:

BFTP

[SteveB]

Because that's the Antarctic, October is mid-Spring down there!

Lol .

Serves me right for not reading it properly.

Still a good increase though!!!

[The PIT]

It would appear that at present the ice is increasing at a faster rate then other year this century apart from 2002 (for this time frame)

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

It would be nice to see 15sqkm2 by early March next year

Be interesting too see what the AGW crowd will say if we have a record freeze this winter. I suspect the goal posts will move thats all.

[Iceberg]

Be interesting too see what the AGW crowd will say if we have a record freeze this winter. I suspect the goal posts will move thats all.

If we have a record freeze I'll eat my pants, become a skeptic and agree with everything that Watts says.

How about we stop the little digs, sillyness and get back to the matters in hand.

[stewfox]

I don't think we can remove the humanity from any discussion that involves change that is unwelcome. Anyone watching a relative fade away knows how easy it is to gain hope from slight improvements when they are set against a steady decline.It is human nature to do just this.

But the relative in question had just won a 100m in 9.3 secs , surely that cant be bad ?

They are bouncing up and down and singing from the top their lungs

I cant see how a gain of over 1 million sq kms of ice cf from 2yrs ago is fading fast ?

2yrs of recovery doesnt = steady decline unless your after her money or have some vested interest in her decline,

Edited September 22, 2009 by stewfox

[Thundery wintry showers]

Take a set of numbers (if you can, think of it as a generic dataset rather than a dataset that has anything to do with AGW).

28, 27, 25, 22, 24, 22, 20, 21, 16, 17, 19

Would the increase in the last two digits mean that the dataset wasn't showing a steady downward trend overall?

[Gray-Wolf]

I'd just posted on the general thread and realised we may have needed that post here to. Seeing as ice extent only requires a 15% (or more) coverage the more open water we accrue over summer allows for a greater distortion in 'ice extent' as the remaining pack can spread out and so long as it covers 15% of the open water will appear as it had when there was 100% ice cover.

Maybe , once ICESAT is up , we need to look at measuring ice volume across the arctic so we can better get a feel for the losses and not become confused when the weather stretches out the ice to cover a larger extent with 15% cover?

[Admiral_Bobski]

Take a set of numbers (if you can, think of it as a generic dataset rather than a dataset that has anything to do with AGW).

28, 27, 25, 22, 24, 22, 20, 21, 16, 17, 19

Would the increase in the last two digits mean that the dataset wasn't showing a steady downward trend overall?

Good example, TWS. The trend is quite clearly downwards.

But!

The dataset could well increase from this point, and without more information we can't say whether or not it will. It is only retrospectively that those last figures will show themselves to be statistically significant or insignificant.

CB

(Stirring the Pot!)

[Thundery wintry showers]

Yes, a fair point, and one which carries over to the specific case of Arctic ice cover.

I am not hopeful of a long-term recovery, but if some of the predictions of global temperatures stalling for another couple of decades due to reduced solar activity come true, then I certainly wouldn't rule out the possibility, at least in the short term.

I don't think we will see a long-term recovery if global temperatures keep rising though.

[osmposm]

But the relative in question had just won a 100m in 9.3 secs , surely that cant be bad ?

They are bouncing up and down and singing from the top their lungs

I cant see how a gain of over 1 million sq kms of ice cf from 2yrs ago is fading fast ?

2yrs of recovery doesnt = steady decline unless your after her money or have some vested interest in her decline,

Because the relative isn't bouncing up and down and singing, Stew. In the last two days the relative has regained partial consciousness, after nearly four previous weeks getting gradually more comatose (albeit with many up-and-down variations in consciousness within that). Is this the start of a full recovery? It's possible, and one passionately hopes so....but it would be unwise to get too excited yet.

Nobody ever said decline was steady.

Ossie

PS The analogy is surprisingly good for anyone who has, like G-W, watched the process. And I must painfully record that almost this precise pattern and timescale was endured by my father, who had an extraordinary, quite unexpected, and almost joyful period of lucidity late in the slow, messy progress of his acute leukemia. He died a few days later. Beware of false hope.....but of course remain open to the possibility.