Author Topic: IJIS (Read 2670248 times)

slow wing · « **Reply #650 on:** March 24, 2014, 08:59:45 AM »

Tor, that is a good question and something I have wondered myself. In fact, I have several questions, particularly about the Winter as snow is an excellent insulator...

How much of a role does it play in retarding the growth of ice thickness over the Winter?

What is the year-to-year variation in that?

Is there a trend over the years?

Is it too cold over the Winter for much snow to fall, given that cold air can't carry much moisture?

Can enough snow fall on ice by early in the Winter to essentially block growth from then on in those places?

If snow falls, does it tend to become hard-packed and stay in place as an effective insulator, or does it instead get blown around into localised drifts?

And mainly to repeat Tor's question: how important is snow fall overall, relative to other physical effects, in the amount of ice growth and its variation?

lanevn · « **Reply #651 on:** March 24, 2014, 09:22:37 AM »

Lol, looks like freezing time for Saint Lawrence again. Looks like this this zone can pretend on latest melt since 1979 ).

Espen · « **Reply #652 on:** March 25, 2014, 04:27:58 AM »

IJIS:

14,079,938 km² (March 24, 2014) down 76,126 km2 from previous date.

Frivolousz21 · « **Reply #653 on:** March 25, 2014, 04:52:06 AM »

The Bering has been getting rocked by the dipole anomaly.

We might see the ice plummet there this Spring if we don't see a pattern change.

jdallen · « **Reply #654 on:** March 25, 2014, 07:30:31 AM »

Quote from: frivolousz21 on March 25, 2014, 04:52:06 AM

The Bering has been getting rocked by the dipole anomaly.

We might see the ice plummet there this Spring if we don't see a pattern change.

That actually is kinda what I've been anticipating, Friv, but haven't been talking much about.

I'm expecting a very precipitous drop as the peripheral areas melt out, pulling up slightly when the melt starts being driven more by Hudson & Baffin bay, Kara, ESS, Laptev and Chukchi seas.

The first few weeks I think may be dramatic.

domen_ · « **Reply #655 on:** March 25, 2014, 07:22:39 PM »

Have we reached this year's maximum?

jdallen · « **Reply #656 on:** March 25, 2014, 07:39:35 PM »

Quote from: domen_ on March 25, 2014, 07:22:39 PM

Have we reached this year's maximum?

Quite a number of us think so. The way extent and area numbers seem to be falling off of a cliff supports that. Unless there is a sharp recovery this week, it is virtually certain, as increasing insolation will make it impossible later.

Jim Pettit · « **Reply #657 on:** March 25, 2014, 09:43:21 PM »

Quote from: domen_ on March 25, 2014, 07:22:39 PM

Have we reached this year's maximum?

I believe IJIS/JAXA extent (and CT area, as well) have reached their respective maxima. Especially extent, which has already fallen nearly 370,000 km2 off the maximum set just four days earlier. There's never been a rise anywhere near that large so late in the year, and the forecast says that's not at all likely this year.

jdallen · « **Reply #658 on:** March 25, 2014, 10:15:19 PM »

Quote from: Jim Pettit on March 25, 2014, 09:43:21 PM

Quote from: domen_ on March 25, 2014, 07:22:39 PM
Have we reached this year's maximum?

I believe IJIS/JAXA extent (and CT area, as well) have reached their respective maxima. Especially extent, which has already fallen nearly 370,000 km2 off the maximum set just four days earlier. There's never been a rise anywhere near that large so late in the year, and the forecast says that's not at all likely this year.

What I wonder right now is, has there been any time where extent has dropped that fast, this soon? 3 century drops plus change in 4 days is notable, even in summer, much less now.

Jim Pettit · « **Reply #659 on:** March 25, 2014, 11:32:42 PM »

Quote from: jdallen on March 25, 2014, 10:15:19 PM

Quote from: Jim Pettit on March 25, 2014, 09:43:21 PM
Quote from: domen_ on March 25, 2014, 07:22:39 PM
Have we reached this year's maximum?

I believe IJIS/JAXA extent (and CT area, as well) have reached their respective maxima. Especially extent, which has already fallen nearly 370,000 km2 off the maximum set just four days earlier. There's never been a rise anywhere near that large so late in the year, and the forecast says that's not at all likely this year.

What I wonder right now is, has there been any time where extent has dropped that fast, this soon? 3 century drops plus change in 4 days is notable, even in summer, much less now.

That is a big drop for March; in fact, it's the largest four-day decrease in extent I can find in the September - March time period, at least since 2002. But April has seen such events: 368k just last year; 399k in 2012; 359k in 2006, and the big one, 482k in 2004. And once we're in June and July, such decreases are practically common-place. (The single largest four-day drop I can find [in my admittedly hurried search] was 604k in June of 2012.)

jdallen · « **Reply #660 on:** March 26, 2014, 01:28:19 AM »

Quote from: Jim Pettit on March 25, 2014, 11:32:42 PM

Quote from: jdallen on March 25, 2014, 10:15:19 PM
Quote from: Jim Pettit on March 25, 2014, 09:43:21 PM
Quote from: domen_ on March 25, 2014, 07:22:39 PM
Have we reached this year's maximum?

I believe IJIS/JAXA extent (and CT area, as well) have reached their respective maxima. Especially extent, which has already fallen nearly 370,000 km2 off the maximum set just four days earlier. There's never been a rise anywhere near that large so late in the year, and the forecast says that's not at all likely this year.

What I wonder right now is, has there been any time where extent has dropped that fast, this soon? 3 century drops plus change in 4 days is notable, even in summer, much less now.

That is a big drop for March; in fact, it's the largest four-day decrease in extent I can find in the September - March time period, at least since 2002. But April has seen such events: 368k just last year; 399k in 2012; 359k in 2006, and the big one, 482k in 2004. And once we're in June and July, such decreases are practically common-place. (The single largest four-day drop I can find [in my admittedly hurried search] was 604k in June of 2012.)

Thank you, Jim. It is good to have it on perspective, which I think can be summarized as notable but not exceptional.

Espen · « **Reply #661 on:** March 26, 2014, 05:05:03 AM »

IJIS:

14,044,187 km² (March 25, 2014) down 35,751 km² from previous date.

Espen · « **Reply #662 on:** March 27, 2014, 05:09:55 AM »

IJIS:

14,049,815 km2 (March 26, 2014) up 5,628 km² from previous.

Espen · « **Reply #663 on:** March 28, 2014, 06:15:09 AM »

IJIS:

14,014,943 km² (March 27, 2014) down 34,872 km² from previous.

Espen · « **Reply #664 on:** March 29, 2014, 10:12:30 AM »

IJIS:

13,942,676 km² (March 28, 2014) again below 14 million km² down 72,267 km² from previous.

Espen · « **Reply #665 on:** March 30, 2014, 09:52:21 AM »

IJIS:

13,855,013 km² (March 29, 2014) down 87,663 km² from previous.

Espen · « **Reply #666 on:** March 31, 2014, 05:21:06 AM »

IJIS:

13,848,958 km² (March 30, 2014) down 6,055 km² from previous.

3rd lowest for this date after 2006 and 2007.

And 458,807 km² below 2000s average.

Espen · « **Reply #667 on:** April 01, 2014, 05:14:44 AM »

IJIS:

13,877,174 km² (March 31, 2014) up 28,216 km² from previous.

Espen · « **Reply #668 on:** April 02, 2014, 06:08:08 AM »

IJIS:

13,874,338 km² (April 1, 2014) down 2,836 km² from previous.

Espen · « **Reply #669 on:** April 03, 2014, 05:51:06 AM »

IJIS:

13,857,492 km² (April 2, 2014) down 16,846 km² from previous.

Espen · « **Reply #670 on:** April 04, 2014, 06:08:59 AM »

IJIS:

13,852,747 km² (April 3, 2014) down 4,745 km² from previous.

Espen · « **Reply #671 on:** April 05, 2014, 09:02:53 AM »

IJIS:

13,849,934 km² (April 4, 2014) down 2,813 km² from previous.

Espen · « **Reply #672 on:** April 06, 2014, 09:52:15 AM »

IJIS:

13,889,732 km² (April 5, 2014) up 34,798 km² from previous.

Espen · « **Reply #673 on:** April 07, 2014, 05:14:27 AM »

IJIS:

13,870,023 km² (April 6, 2014) down 19,709 km² from previous.

Espen · « **Reply #674 on:** April 08, 2014, 05:30:29 AM »

IJIS:

13,833,873 km² (April 7, 2014) down 36,150 km² from previous.

Espen · « **Reply #675 on:** April 09, 2014, 05:50:34 AM »

IJIS:

13,784,522 km² (April 8, 2014) down 49,351 km² from previous.

Espen · « **Reply #676 on:** April 10, 2014, 06:06:16 AM »

IJIS:

13,733,392 km² (April 9, 2014) down 51,130 km² from previous.

Espen · « **Reply #677 on:** April 11, 2014, 06:24:39 AM »

IJIS:

13,666,289 km² (April 10, 2014) down 67,103 km² from previous.

jdallen · « **Reply #678 on:** April 11, 2014, 09:06:18 AM »

Quote from: Espen on April 11, 2014, 06:24:39 AM

IJIS:

13,666,289 km² (April 10, 2014) down 67,103 km² from previous.

I'd say... the toboggan has started down the hill....

crandles · « **Reply #679 on:** April 11, 2014, 05:46:58 PM »

Quote from: jdallen on April 11, 2014, 09:06:18 AM

I'd say... the toboggan has started down the hill....

Does that make it worrying that area is going up, to get a good run at it?

jdallen · « **Reply #680 on:** April 11, 2014, 06:57:31 PM »

Quote from: crandles on April 11, 2014, 05:46:58 PM

Quote from: jdallen on April 11, 2014, 09:06:18 AM
I'd say... the toboggan has started down the hill....

Does that make it worrying that area is going up, to get a good run at it?

I've been watching the recent rise in CT area with fascination as well. Not sure what to make of it. The numbers do seem consistent enough to imply it isn't cloud artificially expanding the pack. The new area *will* be thin - I'd say ice forming in some of the huge leads opening in the Laptev and elsewhere in and adjacent to the CAB, while the peripheral sea ice crashes.

It won't have time to get much past pan ice - a few centimeters. It will likely break up and disappear as quickly. If we see some early stacked up century drops in area in May and early June, that would tend to support this.

Stephen · « **Reply #681 on:** April 12, 2014, 02:15:48 AM »

Quote from: jdallen on April 11, 2014, 06:57:31 PM

Quote from: crandles on April 11, 2014, 05:46:58 PM
Quote from: jdallen on April 11, 2014, 09:06:18 AM
I'd say... the toboggan has started down the hill....

Does that make it worrying that area is going up, to get a good run at it?

I've been watching the recent rise in CT area with fascination as well. Not sure what to make of it. ......
....snip....snip...

When talking about the stock market, Keynes once said:
"The market can remain irrational longer than you can remain solvent".

I thought it would be appropriate to paraphrase that with our sea ice predictions and the current reality, but I can't quite get there.

How about "The ice can remain frozen longer than your predictions can remain valid"

Hmmm, doesn't quite work but you get the meaning.

theoldinsane · « **Reply #682 on:** April 12, 2014, 09:19:06 AM »

Stephen, how about this?

"The Arctic can remain insane longer than you can remain sane."

Espen · « **Reply #683 on:** April 12, 2014, 09:28:42 AM »

IJIS:

13,628,682 km² (April 11, 2014) down 37,607 km² from previous.

Espen · « **Reply #684 on:** April 13, 2014, 09:32:42 AM »

IJIS:

13,544,538 km² (April 12, 2014) down 84,144 km² from previous.

Espen · « **Reply #685 on:** April 14, 2014, 05:13:59 AM »

IJIS:

13,489,773 km² (April 13, 2014) down 54,765 km²from previous.

Espen · « **Reply #686 on:** April 15, 2014, 05:42:22 AM »

13,475,017 km² (April 14, 2014) down 14,702 km² from previous.

Espen · « **Reply #687 on:** April 16, 2014, 06:02:18 AM »

IJIS:

13,427,583 km² (April 15, 2014) down 47,434 km² from previous.

Lennart van der Linde · « **Reply #688 on:** April 17, 2014, 07:23:06 AM »

Century break: 13,321,362 km2 (April 16, 2014) down 106k from previous

Espen · « **Reply #689 on:** April 17, 2014, 07:28:30 AM »

IJIS:

13,321,362 km² (April 16, 2014) down 106,221 km² from previous.

And still 4th lowest for the date.

Espen · « **Reply #690 on:** April 18, 2014, 07:01:24 AM »

IJIS:

13,255,763 km² (April 17, 2014) down 65,599 km² from previous.

3rd lowest for this date.

Frivolousz21 · « **Reply #691 on:** April 18, 2014, 08:46:46 AM »

Yeah and the pattern is freaking horrible

Espen · « **Reply #692 on:** April 20, 2014, 06:46:34 AM »

IJIS:

13,231,029 km² (April 18, 2014) down 24,734 km² from previous.

3rd lowest for this date.

Espen · « **Reply #693 on:** April 20, 2014, 06:52:19 AM »

IJIS:

13,193,343 km² (April 19, 2014) down 37,686 km² from previous.

2nd lowest for this date, only 2004 was lower.

Espen · « **Reply #694 on:** April 21, 2014, 06:12:13 AM »

IJIS:

13,177,428 km² (April 20, 2014) down 15,915 km² from previous.

2nd lowest for this date, 2004 was lower at 13,024,968 km².

Espen · « **Reply #695 on:** April 22, 2014, 05:17:32 AM »

IJIS:

13,174,019 km² (April 21, 2014) down 3,409 km² from previous.

3rd lowest for this date. 2004 and 2007 was lower.

Espen · « **Reply #696 on:** April 23, 2014, 05:15:53 AM »

IJIS:

13,115,859 km² (April 22, 2014) down 58,160 km² from previous.

3rd lowest for this date. 2004 and 2007 was lower.

Espen · « **Reply #697 on:** April 24, 2014, 05:13:57 AM »

IJIS:

13,097,680 km² (April 23, 2014) down 18,179 km² from previous.

3rd lowest for this date. 2004 and 2007 was lower.

Espen · « **Reply #698 on:** April 25, 2014, 06:08:15 AM »

IJIS:

13,068,484 km² (April 24, 2014) down 29,196 km2 from previous.

3rd lowest for this date. 2004 and 2007 was lower.

Espen · « **Reply #699 on:** April 26, 2014, 09:28:04 AM »

IJIS:

13,036,431 km² (April 25, 2014) down 32,053 km² from previous.

3rd lowest for this date. 2004 and 2007 was lower.

News:

Author Topic: IJIS (Read 2670248 times)