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plinius

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Re: 2015 sea ice area and extent data
« Reply #300 on: May 09, 2015, 12:59:56 PM »
nonsensical point.
Cutting measurement digits is an as bad as widespread practice that dates back to times when people used pen and pencil to calculate their numbers. Your computer does not care about that and in fact this malpractice creates some problems (e.g. on axis rescaling). So, let him report his full numbers, your screen won't burn down, and you have hopefully the knowledge to read an error bar.

jdallen

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Re: 2015 sea ice area and extent data
« Reply #301 on: May 09, 2015, 05:35:43 PM »
Thinking about the discussion of the current state of the ice, and it's potential to pass 2012, I indulged in a quick exercise using archived IJIS data. I briefly evaluated the loss from this date for the years 2004 through 2014, and came up with the minimum, maximum and average IJIS extent loss between May 7th and the years final minumum.  I came up with this:

IJIS Extent Loss from 5/7 to Minimum, 2004-2014
Max Loss   9391972
Min Loss   7024081
Average Loss   7943161
Median Loss   8002714

I submit these values give us the effect of weather combined with "momentum" - the effect of heat previously applied (or not) during the prior 6 months or so.  From that, I think we can extrapolate  some end points which probably define the range within which the 2015 minimum will fall:


Potential 2012 Minimum based on the above numbers
2015 Minus Average Loss   4446987
2015 Minus Minimum Loss   5366067
2015 Minus Maximum Loss   2998176
2015 Minus Median Loss   4387434

I've added in median, as its offset from Average tends to reflect our trend, and what is more typical from 2007 onwards.

The upshot of this is, with a loss similar to 2012, we beat it by about 200,000KM2
With the same loss as 2004 (minimum loss), we still end up 8th lowest SIE overall, ahead of 2004 and 2006
With the average loss (Less than 2013, slightly more than 2014), we pass all years except 2007, 2011 and 2012 to take over 4th place, ditto median.

So I'd say, the most probable outcome is we end up somewhere around 2011 at the end of the melt season.  However, there is a caveat:  All the loss numbers are inside the 2SD threshold, and all but one is within 1SD of the average.  The situation is still very volatile, but I think highlights just how vulnerable things are. 

Based on that, it implies to me that there is a better than 40% chance we will pass 2012 this year.
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DavidR

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Re: 2015 sea ice area and extent data
« Reply #302 on: May 10, 2015, 02:03:21 AM »
CT is back again!

My last prediction, calculated fro NSIDC sea ice concentration data, was:


Wed -36.6 11.797073


Today CT reported:

-36k6 11.796725

That is 0.3k off (about half a "pixel" at 100%)
Do you think that this indicates that numbers displayed to that precision present false certainty?
Perhaps the last 2 didgets could be removed, leaving the last significant figure at 0.1k, or less than 1/4 a pixel. Given the resolution and noise of the data, this difference could even be caused by floating point error accumulations on a even a perfect match of the actual underlying maths. I don't believe these last 2 figures tell us anything
The CT figures are ridiculously accurate.  In a system that  changes at up to  60 km^2 per minute and is measured, in each area, at different times every day; providing a figure that  is precise to  0.1 km^2 is inappropriate precision.

Wipneus is endeavoring, with great success, to replicate the CT calculations but, the CT estimates are the issue.
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plinius

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Re: 2015 sea ice area and extent data
« Reply #303 on: May 10, 2015, 11:45:15 AM »
To hammer the point again: There is no such thing as "ridiculously accurate", There are only people incapable of reading an error bar.
So:
1) Cryosphere is doing very well in not cutting their digits.
2) There are more important things in life as in science than (factually wrong) rants about the number of digits reported.

Peter Ellis

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Re: 2015 sea ice area and extent data
« Reply #304 on: May 10, 2015, 11:59:40 AM »
It's not hard.  Retain all figures during processing, and when providing the raw data to others to enable further processing.   For final display products, cut it down to an appropriate number of digits to avoid implying your results are more precise than they really are.

plinius

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Re: 2015 sea ice area and extent data
« Reply #305 on: May 10, 2015, 12:14:05 PM »
I don't know how often you have dealt with scientific data yourself, but I cannot count the number of times when dear fellow scientists have cut their digits to 1 sigma and I lose information or even cannot scale to a different axis. That's ridiculous. And yes! It's not hard. But mostly I would apply that to the person not able to read the error bars.
If you want to display to people without mathemtical knowledge, you anyway use a graph.

Ever wasted a thought why natural constants are typically provided to 3 error digits and not one? Well...?

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Re: 2015 sea ice area and extent data
« Reply #306 on: May 10, 2015, 12:19:32 PM »
Well, displaying decimal digits digits on integer numbers is not correct, although for practical purposes people are forgiving.
Raw data, that is the key as Peter says. Avoid processing so that the user will do is own. Rounding twice can lead to a *true* error.

BornFromTheVoid

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Re: 2015 sea ice area and extent data
« Reply #307 on: May 10, 2015, 04:20:39 PM »
Update for the week to May 10th

The current 5 day mean is on 12,927,400km2 while the 1 day extent is at 12,805,000km2.
The daily anomaly (compared to 81-10) is at -722,150km2, an increase from -687,360km2 last week. The anomaly compared to the 07, 11 and 12 average is at -313,270km2, an increase from -269,070km2 last week. We're currently 3rd lowest on record, the same as last week.



The average daily change over the last 7 days was -55.7k/day, compared to the long term average of -50.7k/day, and the 07, 11 and 12 average of -49.4k/day.
The average long term change over the next week is -42.8k/day, with the 07, 11, and 12 average being -47.0k/day.



The loss so far this May is the 11th largest on record. To achieve the largest monthly drop, a daily loss of at least 70.6k/day is required, while the smallest drop requires less than 9.0k/day and an average drop requires 39.6k/day.

I recently joined the twitter thing, where I post more analysis, pics and animations: @Icy_Samuel

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Re: 2015 sea ice area and extent data
« Reply #308 on: May 10, 2015, 05:34:53 PM »
BFTVoid....LOVE your stats.  Keep up the good work and THANK YOU....
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helorime

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Re: 2015 sea ice area and extent data
« Reply #309 on: May 13, 2015, 04:16:13 AM »
What happened to Cryosphere today.  Site has been down all day....
Any sufficiently advanced technology is indistinguishable from magic.

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Re: 2015 sea ice area and extent data
« Reply #310 on: May 13, 2015, 07:34:56 AM »
CT still has not updated, here is what I calculate as what will reported when they do:


Fri       11.593455
Sat -127.6 11.465877
Sun -74.8 11.391113
Mon -106.6 11.284509
Tue -81.8 11.202744
Wed -28.3 11.174434
Thu -71.5 11.102919


Jim Pettit

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Re: 2015 sea ice area and extent data
« Reply #311 on: May 13, 2015, 12:42:37 PM »
IJIS Extent:
11,983,392 km2 (12 May)
Down 1,958,668 km2 (14.05%) from 2015 maximum of 13,942,060 km2 on 15 February.
8,805,937 km2 above record minimum extent of 3,177,455 km2 (16 September 2012).
Down 73,327 km2 from previous day.
Down 539,945 km2 over past seven days (daily average: -77,135 km2).
Down 723,624 km2 for the month of May (daily average: -60,302 km2).
563,174 km2 below 2000s average for this date.
288,687 km2 below 2010s average for this date.
181,797 km2 below 2014 value for this date.
561,660 km2 below 2012 value for this date.
3rd lowest May to-date average.
Lowest value for the date.
35 days this year (26.52% year-to-date) have recorded the lowest daily extent.
31 days (23.48%) have recorded the second lowest.
27 days (20.45%) have recorded the third lowest.
93 days (70.45%) in total have been among the three lowest on record.


CT Area:
NOTE: due to (yet another) prolonged absence of official CT sea ice area data, I'm instead using Wipneus' calculated area numbers for the period from 08 May through 12 May (0.3479-0.3589). The official numbers will be inserted if/when available. In the meantime, thanks, Wipneus!
11,174,434 km2 (12 May [Day 0.3589])
Down 2,100,121 km2 (15.82%) from 2015 maximum of 13,274,555 km2 on 17 February [Day 0.1288].
8,940,425 km2 above record minimum area of 2,234,010 km2 (14 September 2012).
Down 28,310 km2 from previous day.
Down 622,291 km2 over past seven days (daily average: -88,899 km2).
Down 832,035 km2 for the month of May (daily average: -69,336 km2).
496,295 km2 below 2000s average for this date.
204,268 km2 below 2010s average for this date.
243,553 km2 below 2014 value for this date.
451,665 km2 below 2012 value for this date.
3rd lowest May to-date average.
3rd lowest value for the date.
7 days this year (5.3% year-to-date) have recorded the lowest daily area.
15 days (11.36%) have recorded the second lowest.
21 days (15.91%) have recorded the third lowest.
43 days in total (32.58%) have been among the lowest three on record.

Buddy

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Re: 2015 sea ice area and extent data
« Reply #312 on: May 13, 2015, 01:09:23 PM »
WOW.  Something to chew on when looking at May 7th vs May 12th......for that 5 day period:
==============================================================

IJIS Current extent 421,854 km2 below 2012 for May 7th
IJIS Current extent 561,660 km2 below 2012 for May 12th

Additional 140,000 (rounded) loss compared to record year of 2012 (28,000 km2 per day)
-------------------------------------------------------------------------------------------

CT Area 271,646 km2 below 2012 for May 7th
CT Area 451,665 km2 below 2012 for May 12th

Additional 180,000 (rounded) loss compared to record year of 2012 (36,000 km2 per day)


And the beat goes on.........


 
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Yuha

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Re: 2015 sea ice area and extent data
« Reply #313 on: May 13, 2015, 04:50:20 PM »

IJIS Current extent 561,660 km2 below 2012 for May 12th

[...]

CT Area 451,665 km2 below 2012 for May 12th


Almost all of the difference to 2012 comes from just one region: Bering. Eyeballing the regional graphs of Wipneus (not the same but likely similar to IJIS and CT), the difference in Bering is about 500,000 km2 in extent and about 400,000 km2 in area.

oren

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Re: 2015 sea ice area and extent data
« Reply #314 on: May 13, 2015, 08:34:57 PM »

IJIS Current extent 561,660 km2 below 2012 for May 12th

[...]

CT Area 451,665 km2 below 2012 for May 12th


Almost all of the difference to 2012 comes from just one region: Bering. Eyeballing the regional graphs of Wipneus (not the same but likely similar to IJIS and CT), the difference in Bering is about 500,000 km2 in extent and about 400,000 km2 in area.

Besides Bering, which makes up most of the anomaly, the CAA and Hudson have both taken an early dip in those graphs. It's still tiny, but might be interesting if it develops further.

jdallen

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Re: 2015 sea ice area and extent data
« Reply #315 on: May 13, 2015, 10:12:04 PM »
What happened to Cryosphere today.  Site has been down all day....
I tracked down contact information for the Atmospheric Sciences department at UIL, and emailed who I think are the principles, as well as sending a note to the "generic" inbox.

If I get anything back, I'll let you know.

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Re: 2015 sea ice area and extent data
« Reply #316 on: May 14, 2015, 04:39:32 PM »
No update yet, my calculations indicate an uptick on Saturday (thanks to some Beaufort "recovery"):

Fri       11.593455
Sat -127.6 11.465877
Sun -74.8 11.391113
Mon -106.6 11.284509
Tue -81.8 11.202744
Wed -28.3 11.174434
Thu -71.4 11.102998
Fri -41.9 11.061100
Sat +52.5 11.113586


Jim Pettit

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Re: 2015 sea ice area and extent data
« Reply #317 on: May 15, 2015, 01:44:18 PM »
Cross-posted from teh IJIS thread:

No extent number this morning; just a redirect to IJIS's twitter feed. The most recent tweets:

ADSは大規模メンテナンスを行うため5月15日12:00から5月20日12:00までサービスを停止させます。メンテナンス状況についてTwitterでアナウンスいたします。

(ADS will stop the service from May 15 12:00 order to carry out large-scale maintenance to 12:00 May 20 . For maintenance situation will announce on Twitter.)

...followed by:

本日12:00よりADSのサービスは停止させております。大規模メンテナンスを実行中です。

(ADS of service from 12:00 today , we have to stop . We are running a large-scale maintenance .)

So if I'm reading this correctly: no extent numbers until next week. Which, even coupled with the lack of CT area numbers, is no big deal; it's not like it's the melt season or anything... :)

epiphyte

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Re: 2015 sea ice area and extent data
« Reply #318 on: May 15, 2015, 09:21:04 PM »
Does anyone know if it's just the back-end that they are doing maintenance on, or will there be a gap in the data? The former would be understandable given that they are probably getting a bunch of extra traffic due to CT's extended absence...

If the latter - then it seems that they probably picked the worst possible time.

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Re: 2015 sea ice area and extent data
« Reply #319 on: May 15, 2015, 11:23:43 PM »
Does anyone know if it's just the back-end that they are doing maintenance on, or will there be a gap in the data? The former would be understandable given that they are probably getting a bunch of extra traffic due to CT's extended absence...

If the latter - then it seems that they probably picked the worst possible time.
I've sent mail to the CT folks asking what's going on. No response as yet.
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Re: 2015 sea ice area and extent data
« Reply #320 on: May 16, 2015, 12:03:16 AM »
I've had an email back from NASA:

Quote
It's nice to see the science results getting out there! The [IceBridge] sea ice thickness data hasn't finished processing yet, I'm hoping it will finish over the weekend. Once it is done it will be given to NSIDC to be published. Since this is a time sensitive project I'll push them to get it up ASAP, with luck it should be up sometime next week.
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Re: 2015 sea ice area and extent data
« Reply #321 on: May 16, 2015, 08:41:09 AM »
Does anyone know if it's just the back-end that they are doing maintenance on, or will there be a gap in the data? The former would be understandable given that they are probably getting a bunch of extra traffic due to CT's extended absence...

If the latter - then it seems that they probably picked the worst possible time.

AMSR2 data and products are still available from Jaxa. It is just the ADS-NIPR, and perhaps only their website that is not working. Unfortunately it includes the new and now very interesting sea ice thickness/melting maps.

In the mean time, my calculation (based on Uni Hamburgs Sea Ice Concentration  from AMSR2) of extent shows -43k for 2015-05-15.

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Re: 2015 sea ice area and extent data
« Reply #322 on: May 16, 2015, 02:24:29 PM »
If I didn't know better, I'd say the site problems are the result of a coordinated attack to blind us from what is happening during this melt season.

(Adjusts foil cap.)

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Re: 2015 sea ice area and extent data
« Reply #323 on: May 16, 2015, 05:42:47 PM »
The CT web site is up and running once again. The data currently only goes as far as May 8th though.
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Re: 2015 sea ice area and extent data
« Reply #324 on: May 16, 2015, 06:05:06 PM »
An hour ago , it was the 7th, now, it's the 9th.....Looks like by the end of the day, they will be up to date.

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Re: 2015 sea ice area and extent data
« Reply #325 on: May 16, 2015, 08:56:51 PM »
They have caught up, to reveal this (with the noise removed)
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Re: 2015 sea ice area and extent data
« Reply #326 on: May 17, 2015, 03:14:20 AM »
There's that uptick as predicted by Wipneus.   

That image also nicely exposes some of the nonsense that was being spoken during the winter maximum.  The raw numbers of area and extent during the winter maximum seem to have any correlation at all to the numbers in May when they all converge. 
« Last Edit: May 17, 2015, 03:29:48 AM by Stephen »
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Re: 2015 sea ice area and extent data
« Reply #327 on: May 17, 2015, 05:24:32 AM »
There's that uptick as predicted by Wipneus.   

That image also nicely exposes some of the nonsense that was being spoken during the winter maximum.  The raw numbers of area and extent during the winter maximum seem to have any correlation at all to the numbers in May when they all converge.
Careful.  They may all have close to the same slope, but check the offsets carefully at the same juncture. I see differences.

I think also you need to consider the impact of missing ice will have on how things melt out. That's yet to be determined, but really isn't starting well at all.
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Stephen

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Re: 2015 sea ice area and extent data
« Reply #328 on: May 17, 2015, 06:49:25 AM »
There's that uptick as predicted by Wipneus.   

That image also nicely exposes some of the nonsense that was being spoken during the winter maximum.  The raw numbers of area and extent during the winter maximum seem to have any correlation at all to the numbers in May when they all converge.
Careful.  They may all have close to the same slope, but check the offsets carefully at the same juncture. I see differences.

I think also you need to consider the impact of missing ice will have on how things melt out. That's yet to be determined, but really isn't starting well at all.

My point is that none of those differences could have been predicted just by looking at the winter maximum figures. 
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The ice was all around:
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Re: 2015 sea ice area and extent data
« Reply #329 on: May 17, 2015, 07:39:31 AM »
@stephen - your point re: the pointlessness of extrapolating from winter extent/area is well-taken.

Still, It's not winter now - and extent convergence with past years notwithstanding, things do appear to be shaping up into something which, whilst far from predictable, seems potentially outside the bounds of past experience.

I've used this analogy before - but not this early in the year... The CAB ice looks stretched; thin. In the words of Bilbo Baggins: "Like butter spread over too much bread."

...and it's only getting more diaphanous. If things keep going the way they have so far, I think this might be the year that it all comes home to roost.


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Re: 2015 sea ice area and extent data
« Reply #330 on: May 17, 2015, 10:20:50 AM »
@stephen - your point re: the pointlessness of extrapolating from winter extent/area is well-taken.

Still, It's not winter now - and extent convergence with past years notwithstanding, things do appear to be shaping up into something which, whilst far from predictable, seems potentially outside the bounds of past experience.

One of the interesting aspects of this year is that so far it has not been a particularly warm year across the arctic, unlike 2014 which was comparatively  warm throughout Feb- Apr.  April was only about  12th warmest and February 15th.  March  was 4th  but still cooler than 2014. 
Despite this the rate of melt  has been strong. But ultimately it is the arctic temperature from now on that  will  determine the final melt.
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Re: 2015 sea ice area and extent data
« Reply #331 on: May 17, 2015, 02:30:10 PM »

CT Area:
10,987,263 km2 (16 May [Day 0.3699])
Down 2,287,293 km2 (17.23%) from 2015 maximum of 13,274,555 km2 on 17 February [Day 0.1288].
8,753,253 km2 above record minimum area of 2,234,010 km2 (14 September 2012).
Down 126,201 km2 from previous day.
Down 403,355 km2 over past seven days (daily average: -57,622 km2).
Down 1,019,206 km2 for the month of May (daily average: -63,700 km2).
463,569 km2 below 2000s average for this date.
102,325 km2 below 2010s average for this date.
119,246 km2 below 2014 value for this date.
193,752 km2 below 2012 value for this date.
3rd lowest May to-date average.
3rd lowest value for the date.
7 days this year (5.15% year-to-date) have recorded the lowest daily area.
16 days (11.76%) have recorded the second lowest.
23 days (16.91%) have recorded the third lowest.
46 days in total (33.82%) have been among the lowest three on record.

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Re: 2015 sea ice area and extent data
« Reply #332 on: May 17, 2015, 02:57:39 PM »
CT area might see some massive drops as the torch spreads to over half the Pacific.   Ct concentration will drop.

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Re: 2015 sea ice area and extent data
« Reply #333 on: May 17, 2015, 04:07:43 PM »
Update for the week to May 17th

The current 5 day mean is on 12,632,800km2 while the 1 day extent is at 12,531,000km2.
The daily anomaly (compared to 81-10) is at -717,100km2, a decrease from -722,150km2 last week. The anomaly compared to the 07, 11 and 12 average is at -278,530km2, a decrease from -313,270km2 last week. We're currently 3rd lowest on record, the same as last week.



The average daily change over the last 7 days was -42.1k/day, compared to the long term average of -42.8k/day, and the 07, 11 and 12 average of -47.0k/day.
The average long term change over the next week is -46.5k/day, with the 07, 11, and 12 average being -42.8k/day.



The loss so far this May is the 14th largest on record. To achieve the largest monthly drop, a daily loss of at least 83.9k/day is required, while the smallest drop requires less than 6.4k/day and an average drop requires 38.5k/day.

I recently joined the twitter thing, where I post more analysis, pics and animations: @Icy_Samuel

Jim Pettit

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Re: 2015 sea ice area and extent data
« Reply #334 on: May 18, 2015, 01:00:39 PM »
FWIW, ADS_NIPR says we'll have extent numbers back on Wednesday:


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Re: 2015 sea ice area and extent data
« Reply #335 on: May 19, 2015, 09:48:44 AM »
Thanks Jim, the thickness data is available again as well.
The melting in the Beaufort/Chukchi seems now  to have seriously started.

Neven

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Re: 2015 sea ice area and extent data
« Reply #336 on: May 19, 2015, 11:27:37 AM »
What's the grey/violet stuff?  :o
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seaicesailor

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Re: 2015 sea ice area and extent data
« Reply #337 on: May 19, 2015, 11:33:11 AM »
melt ponds ?  ::)
I am obsessed and see melt ponds behind every corner

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Re: 2015 sea ice area and extent data
« Reply #338 on: May 19, 2015, 11:35:23 AM »
Thanks Jim, the thickness data is available again as well.
The melting in the Beaufort/Chukchi seems now  to have seriously started.

A key would be much appreciated here. :)

Neven

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Re: 2015 sea ice area and extent data
« Reply #339 on: May 19, 2015, 11:44:08 AM »
melt ponds ?  ::)
I am obsessed and see melt ponds behind every corner

Indeed, that's why I ask!  ;D
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Neven

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Re: 2015 sea ice area and extent data
« Reply #340 on: May 19, 2015, 11:46:36 AM »
Thanks Jim, the thickness data is available again as well.
The melting in the Beaufort/Chukchi seems now  to have seriously started.

I've decided to stop being lazy:

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silkman

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Re: 2015 sea ice area and extent data
« Reply #341 on: May 19, 2015, 12:12:39 PM »
Nice pic from the Barrow webcam of shoreline melt ponds.

oren

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Re: 2015 sea ice area and extent data
« Reply #342 on: May 19, 2015, 12:21:41 PM »
Melt ponds indeed! nice pic.

Jim Pettit

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Re: 2015 sea ice area and extent data
« Reply #343 on: May 19, 2015, 01:32:34 PM »
IJIS Extent:
11,675,662 km2 (18 May)
Down 2,266,398 km2 (16.26%) from 2015 maximum of 13,942,060 km2 on 15 February.
8,498,207 km2 above record minimum extent of 3,177,455 km2 (16 September 2012).
Down 75,902 km2 from previous day.
Down 381,057 km2 over past seven days (daily average: -54,437 km2).
Down 1,031,354 km2 for the month of May (daily average: -57,297 km2).
598,255 km2 below 2000s average for this date.
319,029 km2 below 2010s average for this date.
244,602 km2 below 2014 value for this date.
490,401 km2 below 2012 value for this date.
2nd lowest May to-date average.
Lowest value for the date.
41 days this year (29.71% year-to-date) have recorded the lowest daily extent.
31 days (22.46%) have recorded the second lowest.
27 days (19.57%) have recorded the third lowest.
99 days (71.74%) in total have been among the three lowest on record.

Wipneus

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Re: 2015 sea ice area and extent data
« Reply #344 on: May 19, 2015, 04:37:17 PM »
CT is not back to daily updates yet. Here are the expected values missing and coming:


Sun       10.987263
Mon -11.8 10.975422
Tue -118.6 10.856866
Wed -15.0 10.841865
Thu -75.4 10.766505


BTW, from that -75k4, Beaufort's contribution is negative: it increases +39k.

Gray-Wolf

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Re: 2015 sea ice area and extent data
« Reply #345 on: May 19, 2015, 06:18:37 PM »
Could this be the collapse and spread of the agglomerate ice floes as the FY ice cement melts out/fails? The modis images show 'large floes' riddled with fractures and I have to wonder if this is a patchwork of survival floes glued together with FY ice? This does not bode well as that 'thick,good' ice could really be Swiss cheese remnants of previous seasons in-filled with FY ice?

It often occurs with Bering at the start of the season as the ice breaks up and flows south extending the 15 or 30% threshold and we see ( what I call) 'false gains'.

Sadly we did not see this this year as ice in Bering was absent ( warm water influx, via the Alaskan current, from 'the blob' keeping ice formation at a min?).
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seaicesailor

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Re: 2015 sea ice area and extent data
« Reply #346 on: May 19, 2015, 07:32:10 PM »
Could this be the collapse and spread of the agglomerate ice floes as the FY ice cement melts out/fails? The modis images show 'large floes' riddled with fractures and I have to wonder if this is a patchwork of survival floes glued together with FY ice? This does not bode well as that 'thick,good' ice could really be Swiss cheese remnants of previous seasons in-filled with FY ice?

It often occurs with Bering at the start of the season as the ice breaks up and flows south extending the 15 or 30% threshold and we see ( what I call) 'false gains'.

Sadly we did not see this this year as ice in Bering was absent ( warm water influx, via the Alaskan current, from 'the blob' keeping ice formation at a min?).

There has been area increase, not extent.
I assume tomorrow twice as much decrease than today's increase. CT area is very noisy day by day at regional level.

Those floes are huge, bear in mind, Manhattan-like floes

BornFromTheVoid

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Re: 2015 sea ice area and extent data
« Reply #347 on: May 19, 2015, 07:55:17 PM »
Daily NSIDC extent now lowest on record. The 5 day trailing average should be 2nd lowest tomorrow and possibly lowest on record the day after, if moderate extent drops continue.
I recently joined the twitter thing, where I post more analysis, pics and animations: @Icy_Samuel

jdallen

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Re: 2015 sea ice area and extent data
« Reply #348 on: May 19, 2015, 08:30:42 PM »
Daily NSIDC extent now lowest on record. The 5 day trailing average should be 2nd lowest tomorrow and possibly lowest on record the day after, if moderate extent drops continue.

Low extent start, early push to get moving, average losses from there already suggests we end up between 2011 and 2012... If we are lucky.
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Wipneus

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Re: 2015 sea ice area and extent data
« Reply #349 on: May 20, 2015, 07:07:34 AM »
From the ADS-NIPR Jaxa thickness/melting map, a new animation of the progressing melt in the Beaufort & Chukchi regions. The "bare" images seems to cause some confusion, so I have added the color bars.

(click req'd)
« Last Edit: May 20, 2015, 07:21:35 AM by Wipneus »