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Paul Klemencic

Yes, Neven, this is the preliminary, and the final usually adds detail (missing ice) in this area. But the last five days have seen the pack in the vicinity of the "Laptev Bite" pushed toward Severnaya Zemlya, then as the LP system moved in, sent rapidly the other direction. There have been open seas in this area for weeks. so this was the coup de gras for the ice that had tried to hang on.

This isn't the only place were the buffeting over the last week is creating big vacancies. The Arm in the E. Siberian is on the verge of a similar quick opening event, as it splits apart. In addtion the Arm is being pushed toward the Siberian coast, although a lot melted, or dispersed out, in the preliminary map (final map will pick up some of the ice missed). In that region, several hundred thousand sq km of ice moved over warmer seas in the last five days.

We should see some significant extent declines as a result of these events, particularly in the more sensitive 6.25 km grid products.

Chris Biscan

If a clyclone is 985mb and powerful but the HP it's interacting with is 1005mb and strung out the gradient is weak.


if the cyclone is 1000mb and the Hp is strong at 1050mb the gradient is much stronger.

placement and other features matter as well.


this has been on going for days by two separate cyclones.

I was surprised yesterday when it didn't open up more. finally happened today.

also the weak ice in the East Greenland Sea moved back big time.

as well as the fram, kara, ESB and Beaufort.

Id go with 60,000km2 loss on Jaxa and start there.

Espen

As I noted on "The fat lady is humming", when this can happen,in such a short time, there is still a potential of loosing 400 - 500 km2 in the East Siberian and Laptev Sea area and plus some minor areas elsewhere especially East Greenland.
Regards Espen

Andrew Xnn

Temperatures in that part of the Laptiv sea are slightly below freezing. I shudder to think of it as being "warm".

Espen

Andrew,

But not really cold by polar standards.

Regards espen

Neven

As I noted on "The fat lady is humming", when this can happen,in such a short time, there is still a potential of loosing 400 - 500 km2 in the East Siberian and Laptev Sea area and plus some minor areas elsewhere especially East Greenland.

I'm definitely not ruling it out, Espen (like I wrote in the latest SIE update). But the weather forecast is such that it would spell an early end to the melting season in the past couple of years (not to mention the pre-2007 era).

Although I must say I see some big high- and low-pressure areas that could do interesting stuff to this ice.

A fascinating battle it will be.

Espen

Yes I am not so much into the weather situation, but conditions are so much different now than ever, specially when it comes to volume, and I dont see or feel much of that where I am watching, we "only" need less than a one third of a century on average the next 12 days to beat 2007!

Regards espen

Bob Wallace

That gif in the upper right corner is sweet.

Wonder if it would be possible to tag the first frame with a date/time stamp, hold there for a moment, run the fade, and tag/hold the last frame?

Neven

I'll give that a try tomorrow, Bob! I wanted to have this out quick and am off to bed now.

Bob Wallace

Sleep? Sleep is for mere mortals.

We've elevated you far above that standing Neven....

Phil263

The laptev "bite" looks a hole in a pancake! will this count as melt for SIE purposes? I thought polynias did not count... (?)
Any way, at this time of year considering that the weather is unfavourable, wouldn't you think that this ice " free" area might refreeze very quickly.
Since there was a large upward revision to the IJIS number for the 4th, isn't this an indication that we will see a very small loss or even a gain for the 5th?

Stevemosher.wordpress.com

beware of readings from microwave in bad weather. On the UB site

No warranty, expressed or implied, is made regarding the accuracy or utility of the data! False ice concentrations can occur due to bad weather systems.

prolly wise to wait. also concretration at the edge is much more prone to error.

Michael Fliss

Is NP-38 going to stay afloat? They are sharing space with the Polarstern. Tread lightly Polarstern!

Michael Fliss

The Polarstern made over 100 nautical miles through the "ice" on Lat N 83-84 in a day (Sept. 5)! What's the rush?

http://www.sailwx.info/shiptrack/shipposition.phtml?call=DBLK

Bob Wallace

I imagine that when the Russians began to realize that it was hard to find two-meter thick ice to place their ice stations on they added flotation.

Chris Biscan

UB final was crazy today.

gonna be a big drop on BREMEN and likely a 75,0001 or more on Jaxa

Bob Wallace

More like a 44.7k drop.

The multiplier for you estimates I'm using is 0.6.

I call it the de-enthusiasm factor. ;o)

Stevemosher.wordpress.com

Bob, yes.

My multiplier is about the same for Chris, just checking back up thread. Nothing wrong with being a bit aggressive as Chris is wont to do, but I find that if I adjust his forecasts consistently downward, I'm rarely disappointed

Chris Biscan

Would everyone else show me there daily public forecasts?

I bet Jaxa makes up for it tomorrow.

I also bet Bremen has a 75,000K or larger single day loss with there final map tonight. We can ask L. Hamilton tomorrow.


Chris Biscan

Steve you are the guy from Watts blog here right?

Bob Wallace

I'm incapable of making daily forecasts. I'm way too new at this game.

I do have an observation however.

It seems like the drops we're seeing now are basically 'melt in place' decreases and not due to strong compacting winds or super-warm winds blowing in from the outside. And there's still a lot of warm water around the edges.

We're logging a 40k+ seven day average decline in these conditions. At this point in 2007 the seven day average was in the mid-twenties, jumped up briefly to 30k and then fell back into the 20ks before falling to zero.

If this sort of drop holds for a couple more days then I'm betting on a new record.

Not betting a lot. I've got a very green, untested model.... ;o)

Lucia (The Blackboard)

I look at the 7 day average minimum. If the extent loss rate and duration between now and the minimum repeats what we saw in 1984, we'll see a new extent minimum with JAXA. So a record can be achieved with extent loss rates that have been observed in the past. I'm not suggesting it's probable, but it's not out of the question based on historic extent loss rates.

Chris Biscan

Bob, you are never to new at it.

Practice makes perfect as they say.


Stevemosher.wordpress.com


Chris,

As I noted there is nothing wrong with being a bit aggressive on your forecasts. And there is nothing wrong with folks noting it. When my skeptical friends ( yes I do consort with disbelievers ) predict really high numbers for extent, I handicap them as well. My daily forecast would consist of averaging all other forecasters and after applying a correction factor for their past performance. Think of it as ensemble averaging.. collectively we are smarter than the individual. At this stage with the state of the ice ( uncharted terriority in many ways) you have to have a lot of balls to put a number down. So, kudos. I learn a lot by reading your take on things. I like crandles most of all cause he speaks my language.

Personally, I think its going to be really close with 2007, but the blowout potential is still there. Either way, I get to go beat up some friends who were predicting 5M+.

Chris Biscan

I am sorry so many have so much invested in this they become afraid to have fun with it.

If someone is wrong they get torched.

It shouldn't be this way.

Then again people like Tony Watts prey on the uninformed and manipulate thing which is disgusting but not surprising when there is $$ to be made. We could make a simple 20 question climate questionnaire based on simple proven facts and the people at Nevens blog vs Watts would blow Watts out of the water. But you won't see people here on Nevens blog treating different opinions or wrong ones with the same vile hate you see over there.

you also won't see people saying Ice Breakers have a more than nothing wrong in melting ice. To bad.

today I probably didn't take in effect the time difference in jaxa vs Bremen and the resolution.

Bremen will be out here in about 20 min I will stay up for that and see if it's as big as the graph shows.

Chris Biscan

00z GFS would have some impressive compaction.

Even with the widespread cold air there would be massive compaction and flushing.


http://vortex.plymouth.edu/gifs/110906070242.gif


Ice in the Fram would go byebye with 2-3 days of 30kt winds blowing out towards the north Atlantic.

Chris Biscan

http://www.iup.uni-bremen.de:8084/amsr/ice_ext_n.png

Bremen plummets as expected.

the Euro is close to the gfs and says compacting and very compacting!

Neven

I have updated the animation (like it better now, Bob Wallace?) as the final map took a bite out of the bite. Still some flash melting to be seen, but not as spectacular as it first seemed.

Neven

Yes Chris B, I think I see it too on the ECMWF forecast map. You are referring to that big low west of Scandinavia, combined with that high over Greenland, right? That should cause the ice pack between Greenland and Svalbard to move towards the Atlantic pretty fast.

Ian Allen

Neven, you spoke of ice going below concentration threshold, but have you noticed that the black and white Bremen map, taken at face value, shows concentrations right down to 1% versus 10% for the color one you seem to prefer. The laptev bite on the prelim was half full of this 1-9% stuff, and there are various other areas where such differences between the 2 maps show up.

Neven

Thanks, Ian. I had totally forgotten about the black and white map (I usually go straight to the archive now). I'll check it next time a large area of low concentration ice 'disappears'.

Twemoran

If we get a low near Greenland won't this cause a large increase in the katabatic winds, possibly enough to overcome the cylonic effect of the low pressure system?

Neven

Twemoran, why would a low cause a large increase in katabatic winds?

Twemoran

Neven - I was recalling my experiences in Southern California with the 'Santa Anna' winds, but Wiki had this specifically about the situation in Greenland

"In Greenland these winds are called Piteraq and are most intense whenever a low pressure area approaches the coast."

Another spring tide on the 9th could add to the fun

Neven

There's a high projected over Greenland, which could mean colder temperatures and thus colder air running off the hills/mountains towards the coast.

Also on Arctic.io's ice drift vector map (see post) you see all arrows coming down, but one big arrow on Greenland pointing eastwards.

So, you're probably right about those katabatic winds, Twemoran. But I'm not sure they overcome the southward cyclonic winds.

New preliminary Uni Bremen map is out. The Laptev Bite fills up some more. Now the ice in the Greenland Sea seems to go.

Bob Wallace

More info is a good thing. I did't realize you included a couple(?) of prelims in the gif.

Is it desirable/necessary to include "prelim" on those frames?

Possibly just tag the first frame with 9/4/11 (smaller font if possible) and the last frame with 9/5/11. Let the dates go away during the gif run.

I'm sort of thinking of a six frame gif. First/second and fifth/sixth same ice picture but date is present on first and sixth.

Start date -> movie runs -> End of movie with date.

Picky, picky, picky....

--

Is it possible to get those previous frames from Breman or do you have to grab them when posted? (I know how to get "yesterday's" version, but only that single bit of history.)

Neven

I've updated the Fram Strait animation. A little bit of flash melting on the 6th. Nothing spectacular.

Bob, Uni Bremen has an archive.

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