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L. Hamilton

A small correction about IARC, they're not Canuckian but of the Alaska persuasion:
International Arctic Research Center at the University of Alaska, Fairbanks.



Oops! Thanks, Larry. Fixed now.


Neven, good news indeed, now we can all get our daily fix.


Daily fix of... open ocean off Banks Island in the Beaufort Sea:


It may be that my memory is terrible, but I don't recall seeing anything as large as that, as early in the melt in previous years.


I saw this earlier today and thought everyone had been playing without me. Looks like for a change I was one of the first to know, not the last.

What a way to start again as well - nearly a double century break.


Interesting how much the extent average has crept over the decades.

Even a CT ice extent that was way above average in 2012 wouldn't necessarily mean a return to levels seen 15 years ago.


I have updated the post with a CAPIE graph and some first impressions.


Double century break (just), and a correction of yesterdays value (now representing a genuine? cb):


The previous values (14 and 15) have not changed.


Strange. I wonder if there's a new algorithm which combines two days of data in the final data point - maybe this gives some indication of what tomorrow's value will be?

Also I seem to remember IJIS updating early morning European time last year, now a much more civilised mid-morning. Have they moved?


Heraclitus as I recall the timing was related to when the satellite passed over the receiving station. Now with a different satellite the crossing time will be different.

Al Rodger

I've uploaded a quick graph that shows how lumpy the new satellite data is compared with previously.
Usually google ask for a second click to see "your attachment."


More good news. Robert Grumbine reports:

AMSR 2 on the way!
My contact inside JAXA sent this note:

GCOM-W1 was launched at 1:39 18 May (Japan Standard Time) as scheduled, and the satellite was separated from the rocket successfully.

This is the satellite carrying the AMSR-2. Keep your fingers crossed for successful deployment. But this is a major step to operations!

k eotw

CT is back up??

not sure if that's already been reported, it's hard to remember with all the stuff coming back online recently


Another big drop in extent reported by IJIS today, but DMI seems to buck the trend: a flat line for two consecutive days ...

Is DMI reporting ahead of other gauges?

L. Hamilton

DMI is currently reporting 5/17, just a -16k decline after +10k the day before. But due to their land mask and boundaries, DMI looks at a smaller Arctic: their 30% extent covers just 9.6m km^2 today, compared with CT 100% area covering 11.2m, or IJIS 15% extent 11.8m. Anybody have this mapped?

So the DMI series doesn't compare directly with others, but rather with itself over time -- as cautioned on their website. Current melting might be happening in areas that CT or IJIS see and DMI doesn't.


Thanks Larry

Account Deleted

A critical stage is passed!

"Japan Aerospace Exploration Agency (JAXA) confirmed that the Global Change Observation Mission 1st - Water "SHIZUKU" (GCOM-W1) successfully deployed the antenna of the Advanced Microwave Scanning Radiometer 2 (AMSR2)* via image data received at the Katsuura Tracking and Communication station."

George Phillies

5/18: Not quite a century break from yesterday, but down 400K from three days ago: 11.816.


The timing of the daily IJIS updates seem to be exactly at 9:56 GMT.

The today values re quite worthless, the correction the next day are larger than the day-to-day differences. Yesterday's value was corrected by about +170k.



Correction: IJIS updates this week were all at 8:56 GMT



Corrections for day -1 (+160k) as well as day -2 (+9k).

Seke Rob

AFAICS, there are multi-day back corrections, not just the day before. Last night picked up the values for 22, 23, 24 and this afternoon for 23, 24, 25.

Date Data@25, Data@24
22nd 11763906 11763906
23rd 11733906 11688125
24th 11742813 11484688
25th 11578281

Means to me that at least 2 full calendar days must have passed before the last day before those can be called, which is reflected in the IJIS notes to data:

"In general, sea-ice extent is defined as a temporal average of several days (e.g., five days) in order to eliminate calculation errors due to a lack of data (e.g., for traditional microwave sensors such as SMMR and SSM/I). However, we adopt the average of latest two days (day:N & day:N-1) to achieve rapid data release. Only for the processing of WindSat data (Oct. 4, 2011 to the present) the data of the day before yesterday (day:N-2) is also sometimes used to fill data gaps."

We'll work with what we got, which is lots more than a few weeks ago. :D

-- Rob


SIE value for May 25 is now 11,674,688....

Frankly,IJIS looks pretty useless this year.
IMHO, we should forget about it and concentrate on the other gauges!

Seke Rob

For all I know the "winds" are ripping ice to shreds. CAPIE will be a pretty good indicator how well the numbers stack up... no close 'feel' for the data right now. For sure a first pass number published on the 25th for the 25th is not exactly solid base, so FTM, guessing the difference is half, which I think Peter Ellis also concluded.


Peter Ellis

I didn't conclude anything whatsoever, other than that we should completely ignore the most recent figure, and treat yesterday's figure with caution.

Even with those caveats, it's at least as rapid/useful as the NSIDC 5-day average (which will thus lag reality by ~2.5 days) and the CT area data (which is also usually a couple of days slow).


Yesterdays (26) update did not include a new value for the day. Just revised the value of the 25th.

Hopefully the IJIS people noticed too that the same day values are causing confusing.

Will see, new update in a few hours.


Wrong assumption. Todays update adds values for the 26th and the 27th (and corrects the value for the 25th).



Looking forward to the thickness update for May. I expect we will still be tracking 2011's volume trend or perhaps a little lower.

Account Deleted


"The Japan Aerospace Exploration Agency (JAXA) confirmed that the Global Change Observation Mission 1st - Water "SHIZUKU" (GCOM-W1) was inserted into a planned position on the A-Train orbit as a result of orbit control performed on June 29, 2012.

JAXA will increase the rotation speed of the AMSR2 aboard the SHIZUKU from the lower rotation mode (11 rpm) to the regular observation mode of 40 rpm to verify its observation performance."

Account Deleted

First images AMSR2!!!



Thanks for this info, Arcticicelost80! As soon as I have my internet connection back at home, I will post about this.

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