Predict Summer 2011 Minimum Arctic Sea Ice Extent (millions sq km)

[tacoman25]

I've already admitted that initially I had an overly-rosy analysis but had corrected that by later in the day on the 15th. Initially I was sort of thrown off by how much colder the 850s were than a month ago.. but then I quickly learned that that is climo for late August and that melt can still occur with widespread -5C 850s.

You'll see that on the 18th I was predicting 30-40k losses on the 19th and 20th (37k and 38k actual) and that by the 21st and 22nd losses would accelerate (70k and 100k actual).

I agree your forecast and my first read on this was wrong for the same reasons. But at first you blamed the models.. which actually performed quite well. That's what I objected to.

Fine, so the modeled pattern wasn't actually off too much.

But both our initial forecasts were both based off the modeled pattern - we both expected a significant deceleration over the past week then, which has not occurred. Thus, we have both been wrong for the same reasons.

[skierinvermont]

Fine, so the modeled pattern wasn't actually off too much.

But both our initial forecasts were both based off the modeled pattern - we both expected a significant deceleration over the past week then, which has not occurred. Thus, we have both been wrong for the same reasons.

I agree with this. But I did not expect as much of a deceleration because I placed greater emphasis on the low concentration and high SSTs (hence my above average forecast of 45k/day made on the 15th). Initially I overreacted to the modeled pattern. By later in the day on the 15th I was expecting only a brief period of slower losses followed by acceleration on the 20th. Which is why I predicted the above average losses.

[tacoman25]

I agree with this. But I did not expect as much of a deceleration because I placed greater emphasis on the low concentration and high SSTs (hence my above average forecast of 45k/day made on the 15th). Initially I overreacted to the modeled pattern. By later in the day on the 15th I was expecting only a brief period of slower losses followed by acceleration on the 20th. Which is why I predicted the above average losses.

The reasoning you gave in this thread was that the pattern beyond the 23rd was unknown. If you were only expecting a brief period of slower losses and then acceleration prior to the 23rd, it wouldn't have made sense to predict just 45k/day losses (just a bit above average).

Your rationale for the 45k/day average was based on the same rationale I had for my 35k/day prediction. It didn't pan out overall, which is why we are both way off at this point. You were not as off as me, but the reason you have been off is the same - you overestimated how much the pattern would slow the melt.

[skierinvermont]

The reasoning you gave in this thread was that the pattern beyond the 23rd was unknown. If you were only expecting a brief period of slower losses and then acceleration prior to the 23rd, it wouldn't have made sense to predict just 45k/day losses (just a bit above average).

Your rationale for the 45k/day average was based on the same rationale I had for my 35k/day prediction. It didn't pan out overall, which is why we are both way off at this point. You were not as off as me, but the reason you have been off is the same - you overestimated how much the pattern would slow the melt.

Obviously my reasoning was not the same as yours or I would have predicted less. I believed and still believe that the very low concentration and warms SSTs would have a detrimental effect and also that the pattern was not as good as we (you and I and others) initially thought it was.

Also I am not "way off at this point." My error is half of yours and I have a decent shot at nearly nailing it if the losses slow down to 40k/day now that the concentration has improved.

[The_Global_Warmer]

We didn't revise last night's first (went from 61k to 59k)...and then your numbers are still a bit off....I get:

Tacoman: +167k

skier: +85k

Friv: +7k

tonights was 58.6Km2 so I am going with 59Km2 for August 24th prelim.

Tacoman: +191k

skier: +99k

Friv: +11k

[tacoman25]

Obviously my reasoning was not the same as yours or I would have predicted less. I believed and still believe that the very low concentration and warms SSTs would have a detrimental effect and also that the pattern was not as good as we (you and I and others) initially thought it was.

Also I am not "way off at this point." My error is half of yours and I have a decent shot at nearly nailing it if the losses slow down to 40k/day now that the concentration has improved.

Your reasoning for the past week was the same as mine. You thought the pattern would result in significant slowing, which did not happen. The difference is that you assumed more melting would occur after the 23rd, once we were beyond reasonable model projections.

[ORH_wxman]

tonights was 58.6Km2 so I am going with 59Km2 for August 24th prelim.

I've been really busy tracking the hurricane, but I'll update these scores in the morning since its annoying to keep revising it when the number changes in the morning. Today was revised to -53k.

[The_Global_Warmer]

I've been really busy tracking the hurricane, but I'll update these scores in the morning since its annoying to keep revising it when the number changes in the morning. Today was revised to -53k.

well there is really no reason to update the prelim anyways. You can just do it with the finals. If you would like.

[The_Global_Warmer]

Obviously my reasoning was not the same as yours or I would have predicted less. I believed and still believe that the very low concentration and warms SSTs would have a detrimental effect and also that the pattern was not as good as we (you and I and others) initially thought it was.

Also I am not "way off at this point." My error is half of yours and I have a decent shot at nearly nailing it if the losses slow down to 40k/day now that the concentration has improved.

I think the losses will probably stay around 40-50km2 a day for the next 2-3 days. But after that we will see them likely go historic for the 29-31st to end August.

and will all due respect the concentration hasn't improved very much.

http://lance-modis.eosdis.nasa.gov/imagery/subsets/?mosaic=Arctic.2011236.aqua.4km

the 00z GFS is in, as well as some early modis images:

http://lance-modis.eosdis.nasa.gov/imagery/subsets/?subset=Arctic_r05c04.2011237.terra

http://lance-modis.eosdis.nasa.gov/imagery/subsets/Arctic_r05c04/2011236/Arctic_r05c04.2011236.terra.1km.jpg

That is one day under favorable winds for 12-18 hours so far.

Already moving 20-30km there.

Areas to the right side under the clouds and south of there have even less concentration. Pretty much the the the entire Russian side of the ice is mostly .5 to 1.5 meters thick. well 1 meter and a lot of it is in shambles.

http://lance-modis.eosdis.nasa.gov/imagery/subsets/?subset=Arctic_r04c04.2011237.terra

That thick white area that is not cracked with water all over the place is coming up as mostly 90% concentration on UB. Take a closer look.

http://lance-modis.eosdis.nasa.gov/imagery/subsets/?subset=Arctic_r04c04.2011237.aqua

That ice is no more than .5 to 1 meter thick.

After day 3 that blob of winds by Russia moves another 200 miles West and Expands East to West Along the entire Eastern Ice pack by day 4.

Models with every run get colder in the medium 4-7 days because climo is less of a factor and real time is more of a factor. We just saw this in the Beaufort which crippled the Beaufort which is also gonna basically sit under 6-12C 850 temp anomolies the next 10 days unless something change.

There is no way if that verfies we see any refreeze and 40km2 losses.

http://lance-modis.eosdis.nasa.gov/imagery/subsets/?subset=Arctic_r03c04.2011236.aqua.500m

That link is to more garbage ice that is .3 to .7 meters thick according to the live reports Polarstern has.

Hell it just compcated 15-25km today while fliushing 30km towards the Fram. under a narrow band of 15-20 kt winds. That is impressive.

I won't make predictions, but stay tuned. as far as Muilti year ice. The Nw Territories is nearly flushed:

http://lance-modis.eosdis.nasa.gov/imagery/subsets/?subset=Arctic_r04c02.2011236.aqua.250m.jpg

And what is left is just nasty.

Now 2010:

http://lance-modis.eosdis.nasa.gov/imagery/subsets/?subset=Arctic_r04c02.2010231.aqua.250m

That ice in 2010 is much thicker. this year's ice is crippled. I think they really need to check bottom melt.

2009:

http://lance-modis.eosdis.nasa.gov/imagery/subsets/Arctic_r04c02/2009235/Arctic_r04c02.2009235.terra.1km.jpg

Much better shape.

[skierinvermont]

I think the losses will probably stay around 40-50km2 a day for the next 2-3 days. But after that we will see them likely go historic for the 29-31st to end August.

and will all due respect the concentration hasn't improved very much.

By improved concentration I mean relative to the normally poor concentration. When I said that we had seen a bump in the area while extent had fallen off. So the ratio between Jaxa extent and area had improved. However, right after I said that the 23rd and 24th saw big drops in area. The area had also started falling in the couple days before I said that but I was still remembering the bump we had seen earlier. So yes now I would agree again concentration is poor after the last 4-5 days of nosediving area.

As for the pattern the next week... I agree it looks poor.

[The_Global_Warmer]

Yes i know they are 850 winds.

teh surface winds will actually be a bit further west and probably just as strong with that gradient.

[The_Global_Warmer]

By improved concentration I mean relative to the normally poor concentration. When I said that we had seen a bump in the area while extent had fallen off. So the ratio between Jaxa extent and area had improved. However, right after I said that the 23rd and 24th saw big drops in area.

I understand.

well I am going on record and saying by September 1st there will be a nice Sea Ice Area Record low extent on Jaxa and CT. I am holding steady with a 2.6 km2 min

as far as extent. Not going there yet...

The euro and GFS are very close.

[nzucker]

Stop posting huge images, Friv, it is annoying and unnecessary.

Use a photo editor to compress or crop them, it is not that complicated and you have been asked the same thing many times.

[skierinvermont]

huh? All of those images fit fine for me. If they were cropped any smaller they wouldn't be legible.

[The_Global_Warmer]

Stop posting huge images, Friv, it is annoying and unnecessary.

Use a photo editor to compress or crop them, it is not that complicated and you have been asked the same thing many times.

800px × 618px

31KB

How small do we need to go with them?

[ORH_wxman]

huh? All of those images fit fine for me. If they were cropped any smaller they wouldn't be legible.

The UB images he posts are enormous and way too large. I asked him several times to stop and even deleted several of them and he completely ignored me. I was nice and never said anything else, but they do get annoying.

[The_Global_Warmer]

The UB images he posts are enormous and way too large. I asked him several times to stop and even deleted several of them and he completely ignored me. I was nice and never said anything else, but they do get annoying.

I've re sized all of them since you asked me that on my screen with those little handles that show up on image sides.

Doesn't that take care of it? If not I won't post them anymore. But I thought that tool worked.

[tacoman25]

How is this looking?

[The_Global_Warmer]

Last data on August 23rd final:

Tacoman: +167k

skier: +85k

Friv: +7k

August 24th: -37,000k

Tacoman: +169k

skier: +77k

Friv: -11k

August 25th: = -29,000K

Tacoman: +163k

skier: +61k

Friv: -37k

August 26th: -46,000K

Tacoman: +174k

skier: +62k

Friv: -46k

August 27th: -20,000k

Tacoman: +159k

skier: +37k

Friv: -81k

August 28th: -26,000k

Tacoman: +150k

skier: +18k

Friv: -112k

The recent downturn has helped Skier and Tacoman. While shooting my error through the roof. Luckily for this contest sakes the expansion in the Beaufort stopped while other areas are seeing compaction/melt pick up. So I expect the next 3 days to be between 50-75K drop per day. If that area between 135E and 105E opens up before September 1st we could get close to a century break. This quick setup changes back to a slow one by September 2nd.

Regardless Skier as this all wrapped up.

[The_Global_Warmer]

August 29th: -68,000k

Tacoman: +183k

skier: +41k

Friv: -99k

[The_Global_Warmer]

-93,000K extent drop tonight on Jaxa.

[Mallow]

Didn't see this thread 'til now (I don't visit this forum very often anymore ), but just statistically speaking, I would have said about 4.8 +/- 0.7 million sq mi

Looks like we'll be on the bottom side of the statistical trend this season.

[The_Global_Warmer]

August 30th: -100,000k

Tacoman: +248k

skier: +96k

Friv: -54k

One day left.

I thought Skier had this in the bag. I underestimated the power of the 15Kt winds on compaction of this thin ice.

[OHSnow]

Congrats Friv! Nice come-from-behind win.

[tacoman25]

Congrats, Friv. As it turned out, the improved pattern and cooler weather overall didn't matter nearly as much as thought.

It will be interesting to see if the much above average melts continue over the next week or so.

[HailMan06]

Congragulations Friv. Now the question is how much more sea ice is going to melt for the year and what the low sea ice extent will be. (likely a new record low)

[The_Global_Warmer]

If I had to put my current line of thought on the role of these factors by percentage for different time periods here goes:

(DIRECT FACTORS, NOT INDIRECT)

natural Variability

GHG's(including Co2)

Temperatures, including SST's

1979-2011:

Natural variability(40%)

GHG's(20%)

Temperatures(40%)

2007-2011:

Natural variability(10%)

GHG's(10%)

Temperatures(80%)

Since 2007 the role of AGW has likely went from 30-40% of the ice decline from 1990-2006. And Temperature feedback has gone up exponentially.

If this process can be shutdown by something else for a while...I can definitely see the ice stopping and gaining volume for a while. Until AGW catches up wit the ever increasing rise of GHG's.

On the flip side if this does not get impeded. We are about to see the ice dramatically drop to possibly near ice free conditions in less then 5 years.

The data on this is clear. The SSTs are crushing the ice from the sides and from below. Not AGW currently, even though natural variability and AGW were triggers for the SSTs to get out of control and decimate the ice.

it is likely since the early to mid 2000s that Ice volume was crippled.

If this continues, we will see the bottom drop out so to speak.

As in the ice as we can see in the laptev will melt out from below, not from the top or sides.

This is a complete admission that i estimated AGW's role in this as a much larger factor then it was and has been.

However SSTs are much more dangerous and deadly for ice in the short term.

[ORH_wxman]

Now that Aug 31st revision is in, we can precisely calculate the average loss for the Aug 14-31 period without estimates...the average daily loss extent was 51.8k per day. Congrats on the win friv.

[The_Global_Warmer]

thanks guys but its looking like my prediction of a 2.6mil km2 sea ice area low is gonna bust hard.

[LakeEffectKing]

Revised Jaxa provides another increase for 9/12.....+5.5k....the 4.51-4.75'ers look to have taken the overall contest....congrats!