Predict Summer 2012 Minimum Arctic Sea Ice Extent (millions sq km)

[The_Global_Warmer]

Good Luck everyone.

http://nsidc.org/arcticseaicenews/

http://sites.google.com/site/arcticseaicegraphs/

There are a couple of links to look at before you make your prediction for some helpful data.

[PhillipS]

My guess of 4.26 - 4.5 M km2 was purely a SWAG that the 2012 melt season will be pretty close to what we saw in 2010.

[The_Global_Warmer]

My guess of 4.26 - 4.5 M km2 was purely a SWAG that the 2012 melt season will be pretty close to what we saw in 2010.

Makes sense, volume will be lower to start

[Jonger]

I'm being bold with 6.0

[skierinvermont]

I'm being bold with 6.0

You mean moronic. Even the WUWT deniers gave up on their annual 6.0 predictions a couple years ago and now generally go with the only modestly less stupid low 5s. Making the same mistake year after year after year = denial.

[Tropopause_Fold]

You mean moronic. Even the WUWT deniers gave up on their annual 6.0 predictions a couple years ago and now generally go with the only modestly less stupid low 5s. Making the same mistake year after year after year = denial.

why so irritable?

hopefully your trip up the AT will calm you down and make you nicer on the internets when you get back.

[skierinvermont]

why so irritable?

hopefully your trip up the AT will calm you down and make you nicer on the internets when you get back.

LOL I'm not irritable - I don't take denier stupidity seriously anymore, it is just amusing and fun to make fun of. My posts probably sound more serious than they are. I'm just being blunt.. if he's offended oh well.

[LithiaWx]

I took a stab, I believe there is no accurate way to predict this number this far out though. You should probably come up with a date to close the poll so folks a month from now don't put in a guess. To keep it fair you should record the votes in the thread and void any other guesses after a certain date...

5.26 - 5.5 - it won't be as bad as 2007 or last year. We are starting out with a higher extent and I think PIOMAS is not as accurate as some believe.

[skierinvermont]

I took a stab, I believe there is no accurate way to predict this number this far out though. You should probably come up with a date to close the poll so folks a month from now don't put in a guess. To keep it fair you should record the votes in the thread and void any other guesses after a certain date...

5.26 - 5.5 - it won't be as bad as 2007 or last year. We are starting out with a higher extent and I think PIOMAS is not as accurate as some believe.

April extent has ZERO correlation to the September minimum. Two of the highest April extents (2008 2010) have two of the lowest minimums and the lowest April extent (2006) has one of the highest minimums. The April Piomas # on the other hand has a fairly good correlation to the September minimum.

[Jonger]

LOL I'm not irritable - I don't take denier stupidity seriously anymore, it is just amusing and fun to make fun of. My posts probably sound more serious than they are. I'm just being blunt.. if he's offended oh well.

Here's a quick tip, the stupid people you are referring to aren't even discussing this matter. So blasting others with insults just shows that you are an internet bully with no control.

[LithiaWx]

April extent has ZERO correlation to the September minimum. Two of the highest April extents (2008 2010) have two of the lowest minimums and the lowest April extent (2006) has one of the highest minimums. The April Piomas # on the other hand has a fairly good correlation to the September minimum.

I predicated my post with "I don't think you can accurately predict a minimum this far out". I was just stating facts on extent and opinion on PIOMAS nothing more and I certainly did not mean to convey a correlation. Your post and those like it are reasons why I hesitated to even post in this thread.

[PhillipS]

I am sorry to see the comments get so ugly so quickly. Could everybody please relax, or switch to decaf, or something? This is an opinion poll, it's not a question of fact or fiction, there's no money riding on it, the fate of the Earth doesn't hinge on being right - so relax and enjoy.

Whoever is closest at the end of the melt season can claim the title of Polar Expert Extraordinaire - Big PEE for short.

[skierinvermont]

I predicated my post with "I don't think you can accurately predict a minimum this far out". I was just stating facts on extent and opinion on PIOMAS nothing more and I certainly did not mean to convey a correlation. Your post and those like it are reasons why I hesitated to even post in this thread.

So "I don't think you can accurately predict a minimum this far out" means that you are intentionally going to make a guess with zero and/or faulty reasoning? If you don't think ice extent is predictable, then guess the 5 year average, which is around 4.8.

Also your claim that PIOMAS is not very accurate is unsubstantiated and easily shown to be false by the extensive validation information conducted by bouys, satellite, and recon that has been presented in this forum.

If you're going to make incorrect unscientific claims in a science forum, expect to be corrected.

[LithiaWx]

So "I don't think you can accurately predict a minimum this far out" means that you are intentionally going to make a guess with zero and/or faulty reasoning? If you don't think ice extent is predictable, then guess the 5 year average, which is around 4.8.

Also your claim that PIOMAS is not very accurate is unsubstantiated and easily shown to be false by the extensive validation information conducted by bouys, satellite, and recon that has been presented in this forum.

If you're going to make incorrect unscientific claims in a science forum, expect to be corrected.

blah, blah, blah... typical hostile response from you. PIOMAS is not as accurate as Extent and hasn't been around very long. Also when we have sufficient ability to verify PIOMAS on a larger scale (more buoys than we currently have) then it will get more credence from me. I've never said PIOMAS is garbage but I do question it's absolute accuracy. Extent is extent and can be compared accurately back to the beginning of the satellite era. Until we have a much larger network that can monitor ice below the surface PIOMAS will always be questionable in my mind. I also think PIOMAS will be shown wrong sooner or later in it's ability, with 100% accuracy, to predict volume.

As for my guess, it's a guess and I stated in another thread to Friv that I thought predicting sea ice maximum this early in the season is foolish but I played along. It took extreme weather patterns to produce 2007 and 2011 results, to believe we will have repeat is bold so I'm going slightly above that five year average. A five year average includes those two anomalous years so I went higher than that, sue me. I wish I had just stayed out of this thread and never participated. Because of doucebags like you this place is intolerable at times. Even a fun thread is turned into a ****storm of negativity and hostile attacks.

[skierinvermont]

blah, blah, blah... typical hostile response from you. PIOMAS is not as accurate as Extent and hasn't been around very long. Also when we have sufficient ability to verify PIOMAS on a larger scale (more buoys than we currently have) then it will get more credence from me. I've never said PIOMAS is garbage but I do question it's absolute accuracy. Extent is extent and can be compared accurately back to the beginning of the satellite era. Until we have a much larger network that can monitor ice below the surface PIOMAS will always be questionable in my mind. I also think PIOMAS will be shown wrong sooner or later in it's ability, with 100% accuracy, to predict volume.

As for my guess, it's a guess and I stated in another thread to Friv that I thought predicting sea ice maximum this early in the season is foolish but I played along. It took extreme weather patterns to produce 2007 and 2011 results, to believe we will have repeat is bold so I'm going slightly above that five year average. A five year average includes those two anomalous years so I went higher than that, sue me. I wish I had just stayed out of this thread and never participated. Because of doucebags like you this place is intolerable at times. Even a fun thread is turned into a ****storm of negativity and hostile attacks.

PIOMAS has published validation and error bars which are peer-reviewed.. but apparently you know something these scientists don't know.. do share. Science isn't conducted by just saying "I just don't think the network's big enough so I think that data isn't accurate." Error bars are calculated based on sampling etc. .. you know .. mathematics and logic.

The 5 year average also includes 2009 which had very favorable weather patterns and a lot more volume and still barely held onto 5.3 in extent.

[skierinvermont]

4.7.. 90% confidence 4.2-5.2.

[LithiaWx]

PIOMAS has published validation and error bars which are peer-reviewed.. but apparently you know something these scientists don't know.. do share. Science isn't conducted by just saying "I just don't think the network's big enough so I think that data isn't accurate." Error bars are calculated based on sampling etc. .. you know .. mathematics and logic.

The 5 year average also includes 2009 which had very favorable weather patterns and a lot more volume and still barely held onto 5.3 in extent.

And they are quite large aren't they? I know that is subjective but please don't sit here and pretend that PIOMAS couldn't use more data to make it more accurate. PIOMAS is far from flawless and you know it.

[skierinvermont]

And they are quite large aren't they? I know that is subjective but please don't sit here and pretend that PIOMAS couldn't use more data to make it more accurate. PIOMAS is far from flawless and you know it.

The error bars are small enough to conclude with high confidence that current volume is either the 1st or 2nd lowest on record (slight chance of 3rd).

[The_Global_Warmer]

The error bars are small enough to conclude with high confidence that current volume is either the 1st or 2nd lowest on record (slight chance of 3rd).

That is true, but even so we have enough supplemental data at this point that we can verify that on many fronts. So it's pretty clear where we stand right now. I would have to put it at 1st worst overall ice pack going into the summer or tied for 1st or a close 2nd.

The Bering SEA SIA Anomaly is currently 400,000km2 higher than last year at this time.

http://www.redorbit.com/news/space/1112508269/esa-nasa-join-forces-to-measure-arctic-sea-ice/

That is one small example of accurate Arctic data tracking.

or more data for Piomas.

That is not even a fraction of it. It looks like the expected min for PIOMAS is around 3000-3400km3, if that does happen, I think we will be able to tell how accurate it is with the data we have this summer.

[dabize]

http://neven1.typepa...64b8107c970b-pi

Have a look at this before guessing.............

The PIOMAS volume is dropping very consistently year over year - question is, what effect will that have on the minimum extent

One year soon, the summer melt is going to take out completely the ice that has been remaining to give high extents over the past few years. This will drop the anomalously high extents quite a bit and have them come into better agreement with the volume estimate given by PIOMAS.

The gamble is: will it be this year?

The talk of and incipient Arctic Dipole has me thinking it will be, and going low.

If one credits PIOMAS, then it will either be close to the 5 year mean (4.7 as Skier suggests for a conservative guess) or it will be something like 3.7.

I'll split the difference and make it 4.2. If I'm wrong, at least I'll have been testing a hypothesis based on a dataset that has only been transformed once.........

[TerryM]

http://neven1.typepa...64b8107c970b-pi

Have a look at this before guessing.............

The PIOMAS volume is dropping very consistently year over year - question is, what effect will that have on the minimum extent

One year soon, the summer melt is going to take out completely the ice that has been remaining to give high extents over the past few years. This will drop the anomalously high extents quite a bit and have them come into better agreement with the volume estimate given by PIOMAS.

The gamble is: will it be this year?

The talk of and incipient Arctic Dipole has me thinking it will be, and going low.

If one credits PIOMAS, then it will either be close to the 5 year mean (4.7 as Skier suggests for a conservative guess) or it will be something like 3.7.

I'll split the difference and make it 4.2. If I'm wrong, at least I'll have been testing a hypothesis based on a dataset that has only been transformed once.........

That's an interesting graph, dividing PIOMAS by area to arrive at a thickness figure. It makes the point expressed yesterday, that if PIOMAS was even with last year, and extent was down, we had to be looking at thinner, probably newer ice.

There is a stark difference between the last two years, and those before them. JAS now trend downward in a gentle slope instead of holding around the peak, then crashing in Oct. Another interesting thing is that 2007, by this metric, is just a middle of the pack year, never distinguishing itself in any way.

I'm going to need some strong coffee before I adjust the bi-focals and try to make sense of this.

[dabize]

That's an interesting graph, dividing PIOMAS by area to arrive at a thickness figure. It makes the point expressed yesterday, that if PIOMAS was even with last year, and extent was down, we had to be looking at thinner, probably newer ice.

There is a stark difference between the last two years, and those before them. JAS now trend downward in a gentle slope instead of holding around the peak, then crashing in Oct. Another interesting thing is that 2007, by this metric, is just a middle of the pack year, never distinguishing itself in any way.

I'm going to need some strong coffee before I adjust the bi-focals and try to make sense of this.

Quite.

The loss of MY ice was of course AFTER the summer of 2007 - its last hurrah. The next summer had much less "old" ice.

Hence my WAG.

BTW, if we had to generate data sets and do statistical tests for the significance of differences between guesses to support our WAGs, my probability field would require a non-parametric stat.

It is bimodal!

[skierinvermont]

Neven's chart is interesting, but is likely overly sensitive to changes in extent if what we are interested in is the thickness of the ice in the arctic ocean and not the peripheral oceans. Neven's graph tells us the mean ice thickness which is reduced when thin peripheral ice is added, even though in reality arctic ocean ice has not gotten thinner.

Here's the math:

Initial condition:

PIOMAS: 20 million km3

CT area: 13 million km2

Piomas/CT: 1.54m mean thickness

Add .5 million in extent @ .4m thick, existing ice remains unchanged:

PIOMAS: 20.2 million km3

CT area: 13.5 million km2

Piomas/CT: 1.50m mean thickness

The Piomas/CT # would lead you to believe that the ice got thinner when it did not.

I will try to create a model which accounts for the fact that peripheral ice is thinner.

[skierinvermont]

Here is an improvement I created over Neven's graph. Ice area over 10 million km2 I set to a thickness of .5m and then subtracted it from the total area and volume. The result is an estimate of the mean thickness of the most northern 10 million km2 of ice. At times of year when there is less than 10 million km2 of ice, it is simply the raw PIOMAS divided by the raw CT area, yielding the same mean thickness as Neven's graph. Below my graph is Neven's graph for comparison.

[skierinvermont]

I accidentally used Ct extent instead of area. It's been corrected.

As you can see the gap between 2011 and 2012 is closed considerably when we subtract out the thin peripheral ice which skews 2012 lower in Neven's graph.

[skierinvermont]

I just discovered another error due to PIOMAS not including leap years and falling behind 9 days from 1979-2012. Will post the corrected graph shortly.

EDIT: original graph has been fixed

As you can see, the disparity between current 2012 and 2011 thickness is reduced by about 75% from Neven's graph to mine. This makes sense given volume remains the same.

[dabize]

Here is an improvement I created over Neven's graph. Ice area over 10 million km2 I set to a thickness of .5m and then subtracted it from the total area and volume. The result is an estimate of the mean thickness of the most northern 10 million km2 of ice. At times of year when there is less than 10 million km2 of ice, it is simply the raw PIOMAS divided by the raw CT area, yielding the same mean thickness as Neven's graph. Below my graph is Neven's graph for comparison.

Nice job.

It doesn't change the fundamental change in the shape of the curve occurring after 2009, though, so it doesn't change the basic calculation re where the threshold might be for increased IE loss, and thus when the best guess would be as to when it kicks in.

It will be interesting to see what happens when the thinnest ice is gone (after the next 3 weeks), and the mean thickness starts to rise.

At some point, the fact that we are looking at extent (not area) is going to become important, and the slope of the thickness drop will start going up. I suspect that that is when we'll be looking at the melt out situation.

[PhillipS]

Bluewave posted this on the Arctice Sea Ice Extent thread.

The first outlook for this season has just been posted:

http://www.arcus.org...tlook/2012/june

I thought it might be interesting to revisit our predictions on the 2012 minimum.

[The_Global_Warmer]

Bluewave posted this on the Arctice Sea Ice Extent thread.

The first outlook for this season has just been posted:

http://www.arcus.org...tlook/2012/june

I thought it might be interesting to revisit our predictions on the 2012 minimum.

Its still far to early to tell but if the min extent is above 5 mil km2 it will take some major intervention from the weather.

[PhillipS]

[bump]