2016 sea ice area and extent data

[AmbiValent]

After looking at the Reanalyzer forecast for the next week, I predict 2016 will still be clearly in the lead (400-600k).

[BornFromTheVoid]

Update for the week to June 4th

The current 5 day trailing average is on 11,011,000km2 while the 1 day extent is at 10,980,000km2.

(All the following data is based on a trailing 5 day average)
The daily anomaly (compared to 81-10) is at -1,450,000km2, a decrease from -1,514,000km2 last week. The anomaly compared to the 07, 11 and 12 average is at -956,000km2, a decrease from -1,021,000km2 last week. We're currently the lowest on record, the same as last week.



The average daily change over the last 7 days was -46.7k/day, compared to the long term average of -55.8k/day, and the 07, 11 and 12 average of -56.0k/day.
The average long term change over the next week is -48.7k/day, with the 07, 11, and 12 average being -77.9k/day.



The extent drop so far this June is the 5th smallest on record. To achieve the largest monthly loss, a drop of at least 104.8k/day is required (requiring ~112.2k/day with with single day values), while the smallest loss requires a drop less than 34.4k/day (<36.0k/day with single day values) and an average loss requires a increase of 57.6k/day (~53.1k/day with single day values).



The extent loss in May was the 3rd largest on record, while the average extent was the lowest on record.

[DavidR]

Thanks. That's now the earliest SIA has been below 9 million km2. But by just five days; I predict that 2016's area will drop (rise?) to second place behind 2012 within the next two weeks (say, June 20).

The most likely date is June 16th, which is when the 2012 plummet finishes. After that 2012 flatlines for 4 days then drops at a pretty average rate for the rest of the month.

If 2016 has average drops for the rest of the month it will be very close to 2012 on June 16th. It will then  retake the lead for the rest of the month.  I  expect 2016 to drop faster than  average and retain its lead. So far this month area has dropped 108K per day, compared with an average of 79K and 2012s,  22K.

[Wipneus]

Shadow CT-area report (based on F18 NSIDC sea ice concentration data, we don't know if it is calibrated):

day  CT-date       NH               SH                Global
Sun 2016.4219 -156.5  9.143601 +100.7  9.460318   -55.8 18.603919
Mon 2016.4247  -97.3  9.046325 +199.8  9.660105  +102.5 18.706430
Tue 2016.4274  -71.5  8.974842  +51.3  9.711446   -20.1 18.686288
Wed 2016.4301  -41.3  8.933579 +148.2  9.859658  +106.9 18.793237

Regionally the numbers diverge, CAB increased (+33), Hudson (-17k), Chukchi (-14k) and Laptev (-13k) lost area.

The shadow NSIDC extent is now at 10.9646 a droplet of  -15.6k. None of the regions did change much.

In the attached delta map many of the (sub-)regional changes can be seen.

[lanevn]

day  CT-date       NH               SH                Global
Sun 2016.4219 -156.5  9.143601 +100.7  9.460318   -55.8 18.603919
Mon 2016.4247  -97.3  9.046325 +199.8  9.660105  +102.5 18.706430
Tue 2016.4274  -71.5  8.974842  +51.3  9.711446   -20.1 18.686288
Wed 2016.4301  -41.3  8.933579 +148.2  9.859658  +106.9 18.793237

And where is current increase in area?

[anotheramethyst]

day  CT-date       NH               SH                Global
Sun 2016.4219 -156.5  9.143601 +100.7  9.460318   -55.8 18.603919
Mon 2016.4247  -97.3  9.046325 +199.8  9.660105  +102.5 18.706430
Tue 2016.4274  -71.5  8.974842  +51.3  9.711446   -20.1 18.686288
Wed 2016.4301  -41.3  8.933579 +148.2  9.859658  +106.9 18.793237

And where is current increase in area?

You're probably thinking of the increase in extent.  You can check the IJIS thread for more detail on that. 

Edit-sorry I didn't see the increase in area mentioned before.  I read the threads in the wrong order, apparently  

[magnamentis]

day  CT-date       NH               SH                Global
Sun 2016.4219 -156.5  9.143601 +100.7  9.460318   -55.8 18.603919
Mon 2016.4247  -97.3  9.046325 +199.8  9.660105  +102.5 18.706430
Tue 2016.4274  -71.5  8.974842  +51.3  9.711446   -20.1 18.686288
Wed 2016.4301  -41.3  8.933579 +148.2  9.859658  +106.9 18.793237

And where is current increase in area?

You're probably thinking of the increase in extent.  You can check the IJIS thread for more detail on that.

the question is legit after reading the below linked post from this morning where he stated that extend & area
increased. thought the same but was sure it will be explained eventually :-) let's see

http://forum.arctic-sea-ice.net/index.php/topic,382.msg79320.html#msg79320

[AmbiValent]

That's data from a different satellite.

[Jim Hunt]

the question is legit after reading the below linked post from this morning where he stated that extend & area
increased. thought the same but was sure it will be explained eventually :-) let's see

That's based on the "Homebrew" AMSR2 based numbers. In this thread Wipneus publishes his DMSP F-18 SSMIS based "Shadow CT" numbers

[seaicesailor]

the question is legit after reading the below linked post from this morning where he stated that extend & area
increased. thought the same but was sure it will be explained eventually :-) let's see

http://forum.arctic-sea-ice.net/index.php/topic,382.msg79320.html#msg79320

These are different measurements of area and extent (NSIDC vs AMSR2 uni hamburg data), different satellites and instrumentation. Wipneus has the attention of sharing his calculations over both datasets.
AMSR2 area is less affected by surface melting, hence it does not depart from AMSR2 extent as much. That much I know :-|

[Sebastian]

Above 2012 by the end of the week/beginning of next week? Jun 8th 2016 is at 8.93m. June 15th 2012 was at ca. 8.0m



( Image from Neven's blog from last year http://neven1.typepad.com/blog/2015/06/asi-2015-update-3-whats-it-going-to-be.html )

[Jim Pettit]

ADS-NIPR Extent:

10,333,107 km2 (06 June)

Down 3,609,400 km2 (25.89%) from 2016 maximum of 13,942,507 km2 on 29 February.

7,155,652 km2 above record minimum extent of 3,177,455 km2 (16 September 2012).

Down 20,208 km2 (-.2%) from previous day.

Down 147,583 km2  (-1.41%) over past seven days (daily average: -21,083 km2).

Down 93,937 km2  (-.77%) for June (daily average: -15,656 km2).

1,057,538 km2 below 2000s average for this date.

544,120 km2 below 2010s average for this date.

256,229 km2 below 2015 value for this date.

838,662 km2 below 2012 value for this date.

Lowest year-to-date (01 January - 06 June) average.

Lowest June to-date average.

Lowest value for the date.

103 days this year (65.61% year-to-date) have recorded the lowest daily extent.

27 days (17.2%) have recorded the second lowest.

14 days (8.92%) have recorded the third lowest.

144 days in total (91.72%) have been among the lowest three on record.

CT Area:

8,933,579 km2 (07 June [Day 0.4302])

Down 3,987,779 km2 (30.86%) from 2016 maximum of 12,921,358 km2 on 29 March [Day 0.2384].

6,699,570 km2 above record minimum area of 2,234,010 km2 (14 September 2012).

Down 41,263 km2 (-.46%) from previous day.

Down 497,475 km2 (-5.32%) over past seven days (daily average: -71,068 km2).

Down 497,475 km2 (-4.47%) for June (daily average: -71,068 km2).

1,048,994 km2 below 2000s average for this date.

617,765 km2 below 2010s average for this date.

666,829 km2 below 2015 value for this date.

728,143 km2 below 2012 value for this date.

Lowest value for the date.

* - NOTE: due to the prolonged absence of official CT sea ice area data, I've incorporated Wipneus' area numbers as calculated from NSIDC data. The official numbers will be inserted if/when available. In the meantime, thanks, Wipneus!

[Wipneus]

Shadow CT-area report (based on F18 NSIDC sea ice concentration data, we don't know if it is calibrated):

day  CT-date       NH               SH                Global
Mon 2016.4247  -97.3  9.046325 +199.8  9.660105  +102.5 18.706430
Tue 2016.4274  -71.5  8.974842  +51.3  9.711446   -20.1 18.686288
Wed 2016.4301  -41.0  8.933828 +148.2  9.859680  +107.2 18.793508
Thu 2016.4329  -44.6  8.889271  +41.4  9.901063    -3.2 18.790334


That would have been a drop of -62.6k if not for "lake ice" which increased by 18.1k. The regions that dropped big are CAA (-26k), Huson (-18k) and Baffin (-14k). On the other side of the Arctic Kara dropped -16k, but the ESS increases 15k.

Shadow NSIDC extent is now 10.9192  dropping -45.5k. Baffin is the big guy here, -32k, followed by Greenland Sea (-16k) and Hudson (-13k).

The attached delta map shows the focus of the changes over the CAA and a new front over the southern Hudson.

[Wipneus]

Shadow CT-area report (based on F18 NSIDC sea ice concentration data, we don't know if it is calibrated):

day  CT-date       NH               SH                Global
Tue 2016.4274  -71.5  8.974842  +51.3  9.711446   -20.1 18.686288
Wed 2016.4301  -41.0  8.933828 +148.2  9.859680  +107.2 18.793508
Thu 2016.4329  -44.4  8.889441  +41.4  9.901071    -3.0 18.790512
Fri 2016.4356  -57.6  8.831831 +104.5 10.005570   +46.9 18.837401

Big disagreements between the regions. ESS increased by 41k, while Caa dropped -32k, CAB -30k, Hudson -21k and Laptev -18k.
Shadow NSIDC is now 10.8651  (-54.1k). Drops are outside the Arctic Basin: Okhotsk (-24k), Hudson (-16k) and Greenland Sea (-14k).

The attached delta map has all the details.

[Wipneus]

Extent and area may drift apart as today's NSIDC sea ice concentration shows.

First the shadow CT-area report notes a fat century :

day  CT-date       NH               SH                Global
Wed 2016.4301  -41.0  8.933828 +148.2  9.859680  +107.2 18.793508
Thu 2016.4329  -44.4  8.889441  +41.4  9.901071    -3.0 18.790512
Fri 2016.4356  -57.2  8.832199 +104.5 10.005600   +47.3 18.837799
Sat 2016.4384 -136.5  8.695739 +147.8 10.153355   +11.3 18.849094

Laptev is here the biggest looser (of area): -49k. Hudson and Baffin each lost -27k, CAB was -21k and the ESS -17k.

The shadow NSIDC came out at 10.8701  a small increase +5.0k. Cause is the Barents Sea extent increase of +26k and only small changes in the other regions.

The attache delta map shows the wide spread concentration drops. All melting in action, waiting for the sun.

[Wipneus]

Also with the data derived from NSIDC gridded sea ice concentration we see a big drop in area and a much smaller drop in extent.

Shadow CT-area report (based on F18 NSIDC sea ice concentration data, we don't know if it is calibrated):

day  CT-date       NH               SH                Global
Thu 2016.4329  -44.4  8.889441  +41.4  9.901071    -3.0 18.790512
Fri 2016.4356  -57.2  8.832199 +104.5 10.005600   +47.3 18.837799
Sat 2016.4384 -136.4  8.695805 +147.8 10.153372   +11.4 18.849177
Sun 2016.4411 -145.8  8.549955 +168.8 10.322178   +23.0 18.872133

Many regions contribute, Kara (-32k), Cab (-29k), Hudson (-24k) and ESS (-22k) are the biggest.

Shadow NSIDC extent is 10.8434  (-26.7k). Kara did a larger drop (-42k), but extent in Baffin increased (+13k).

In the attached delta map, notice the dark colors in the Canadian Archipelago on the one side and in ESS/Laptev on the  other side.

[bbr2314]

Those area plunges are simply enormous especially considering they now make up ~ -1.5% of the remaining pack (each day!).

With temps 80N+ at 0+ the earliest on record per DMI, this should come as no surprise; the stall in extent drops is now manifesting in the area plunge, which should continue for the forseeable future as the CAB ice continues to be yoinked into the Greenland Sea while the main pack is now splitting in two.

[magnamentis]

With temps 80N+ at 0+ the earliest on record per DMI

a very important and accurate observation, many mentioned the "extraordinary heat in 2012, which, looking at the charts more thoroughl, was not that extraordinary and we're now above zero average the earliest indeed and, at least as important, the daily lows around the pole, according to Climate Reanalizer, will stay above zero day and "night" (hours) i know there is not "night" of course, but i think it's clear what i mean.

[jdallen]

Shadow NSIDC extent is 10.8434  (-26.7k). Kara did a larger drop (-42k), but extent in Baffin increased (+13k).

In the attached delta map, notice the dark colors in the Canadian Archipelago on the one side and in ESS/Laptev on the  other side.

The Baffin increase without a doubt is dispersion.  Looking at Worldview there's some large stretches of very "filmy" ice.

I'm expecting ESS and Laptev ice to start coming apart in earnest in about a week.  By then I think the 40-50CM (or more...) of combined top and bottom melt that will have gone on there since the start of the "torch" will have weakened the ice sufficiently it will no longer be able to stand up intact to wind and tide.

[Wipneus]

As reported earlier the conditions for ice surface melting (with associated melt ponds) have taken a sudden stall. The NSIDC sea ice concentration data speaks event more loudly.

Shadow CT-area report (based on F18 NSIDC sea ice concentration data, we don't know if it is calibrated):

day  CT-date       NH               SH                Global
Fri 2016.4356  -57.2  8.832199 +104.5 10.005600   +47.3 18.837799
Sat 2016.4384 -136.4  8.695805 +147.8 10.153372   +11.4 18.849177
Sun 2016.4411 -146.0  8.549799 +168.8 10.322178   +22.8 18.871977
Mon 2016.4438 +100.3  8.650100 +114.6 10.436785  +214.9 19.086885

That is a century increase, almost all caused by the CAB: +87k with Laptev adding +20k to the total. Other regions had only small changes.

Shadow NSIDC extent came out at 10.782.3  (-61.1k). Here Baffin is the single region (-46k), all other regions had much smaller changes.

The attached delta-map shows the increase in concentration in the center of the CAB and a broad swath along the Canadian islands and the north of Greenland.
 

[Jim Pettit]

And just like that, 2016's massive lead over 2012 (which has averaged a whopping 740k since mid-February) has vanished; there's now but a mere 35k of area separating the two years, and with 2012 having dropped nearly 900k over the next six days--and given the current Arctic forecast--expect 2016 to fall behind by up to half a million square kilometers or so in the next week.

FWIW, yesterday's century increase is the largest June one-day rise since 2011, and only the fourth ever in the satellite record.

[jdallen]

FWIW, yesterday's century increase is the largest June one-day rise since 2011, and only the fourth ever in the satellite record.

... and amazingly weird.  The best explanation I have is draining melt ponds.

[oren]

FWIW, yesterday's century increase is the largest June one-day rise since 2011, and only the fourth ever in the satellite record.

... and amazingly weird.  The best explanation I have is draining melt ponds.

Or melt pond refreeze in the CAB?

[jdallen]

FWIW, yesterday's century increase is the largest June one-day rise since 2011, and only the fourth ever in the satellite record.

... and amazingly weird.  The best explanation I have is draining melt ponds.

Or melt pond refreeze in the CAB?

Not sure it's cold enough, with all of the insolation, even through clouds.

[slow wing]

Yep, it has to be a refreeze. The melt ponds over a broad swathe aren't all going to choose to drain on the same day.

+100K! That's a big uptick!

[JKDMaineUSA]

Probably just part of the calibration process that is on going ..

[magnamentis]

glad you mention it, none of the visuals confirms that an Uni Bremen does not show that, hence i'd take it with a prise of salt. temps are a bit high for a large scale refreeze IMO, let's see, but i expect some kind of correction.

[oren]

It could also be wet snow refreezing. I don't know much about the algorithms involved but I seem to remember water on the surface is what decides ice or no ice for the area calculation.

[Wipneus]

It is unpreventable, in June the numbers will go down again even after a century increase.

Here is the shadow CT-area report (based on F18 NSIDC sea ice concentration data, we don't know if it is calibrated):

day  CT-date       NH               SH                Global
Sat 2016.4384 -136.4  8.695805 +147.8 10.153372   +11.4 18.849177
Sun 2016.4411 -146.0  8.549799 +168.8 10.322178   +22.8 18.871977
Mon 2016.4438 +100.3  8.650090 +114.7 10.436848  +215.0 19.086938
Tue 2016.4466  -81.6  8.568522 +187.5 10.624377  +106.0 19.192899

The CAB is still not cooperating (+35k), also ESS is in recovery (+15k). In other regions the summer melting is causing declines, CAA (-33k), Baffin (-25k), Kara (-22k) and Laptev (-21k) are the biggest.

Shadow NSIDC extent is down to 10.6983  (-83.9k). Baffin takes half (-40k), the remains are split up by Kara, Greenland Sea, Barents and Hudson (-22k, -18k, -15k and -14k).

The attached delta map shows an active Arctic with melting and recovery in many places.

[BornFromTheVoid]

Update for the week to June 11th

The current 5 day trailing average is on 10,812,000km2 while the 1 day extent is at 10,698,000km2.

(All the following data is based on a trailing 5 day average)
The daily anomaly (compared to 81-10) is at -1,309,000km2, a decrease from -1,450,000km2 last week. The anomaly compared to the 07, 11 and 12 average is at -610,000km2, a decrease from -956,000km2 last week. We're currently the lowest on record, the same as last week.



The average daily change over the last 7 days was -28.5k/day, compared to the long term average of -48.7k/day, and the 07, 11 and 12 average of -77.9k/day.
The average long term change over the next week is -48.0k/day, with the 07, 11, and 12 average being -82.1k/day.



The extent drop so far this June is the 2nd smallest on record. To achieve the largest monthly loss, a drop of at least 132.9k/day is required (requiring ~141.8k/day with with single day values), while the smallest loss requires a drop less than 36.6k/day (<34.2k/day with single day values) and an average loss requires a drop of 68.3k/day (~69.7k/day with single day values).

[Steven]

Here is the shadow CT-area report (based on F18 NSIDC sea ice concentration data, we don't know if it is calibrated):

day  CT-date       NH                             
Sat 2016.4384 -136.4  8.695805
Sun 2016.4411 -146.0  8.549799
Mon 2016.4438 +100.3  8.650090
Tue 2016.4466  -81.6  8.568522

Thanks for these data.  Comparing your calculated shadow CT-area values for the last few weeks (red dashed line) with the corresponding CT-area values for previous years, 2016 is now virtually tied with 2012  (assuming there are no calibration issues):

[Jim Pettit]

This marks the first time in 103 days--since 12 February--that 2016 SIA has been above 2012. It's also the first time in 55 days that 2016 SIA has been in any position besides first. Among other factoids: even if 2016 were to precisely follow 2012's daily trajectory from now until mid-September--complete with the remainder of that year's steep June cliff and the GAC, etc.--it still wouldn't set a record.

[bbr2314]

This marks the first time in 103 days--since 12 February--that 2016 SIA has been above 2012. It's also the first time in 55 days that 2016 SIA has been in any position besides first. Among other factoids: even if 2016 were to precisely follow 2012's daily trajectory from now until mid-September--complete with the remainder of that year's steep June cliff and the GAC, etc.--it still wouldn't set a record.

How is it a factoid that a year behind another year wouldn't beat that year if it had the same drop as that year? That is common sense.

I think the rhetoric re: optimism is LOLworthy and both models and satellite show massive heat into the Arctic through D10. IMO, the false area drops and rises are a sign that the main pack is now being pre-conditioned. Meanwhile, the peripheral seas are about to start falling apart.

[Jim Pettit]

How is it a factoid that a year behind another year wouldn't beat that year if it had the same drop as that year? That is common sense.

Not sure I follow you. A "factoid" is a trivial bit of information. Do you use an alternate definition of the term?

I think the rhetoric re: optimism is LOLworthy and both models and satellite show massive heat into the Arctic through D10. IMO, the false area drops and rises are a sign that the main pack is now being pre-conditioned. Meanwhile, the peripheral seas are about to start falling apart.

You're missing the point. I'm merely stating facts and figures. For me to say that following 2012's daily behavior from here on would not result in beating that year's record minimum is neither "rhetoric" nor "optimism"; it's just telling it like it is. As to whether it's "LOLworthy" I'll leave up to the individual; I guess some people are just more easily amused. 

[Nick_Naylor]

It IS almost too obvious that - anytime you're not already at record levels - following the subsequent trajectory of the record year won't lead to a new record.

[bbr2314]

How is it a factoid that a year behind another year wouldn't beat that year if it had the same drop as that year? That is common sense.

Not sure I follow you. A "factoid" is a trivial bit of information. Do you use an alternate definition of the term?

I think the rhetoric re: optimism is LOLworthy and both models and satellite show massive heat into the Arctic through D10. IMO, the false area drops and rises are a sign that the main pack is now being pre-conditioned. Meanwhile, the peripheral seas are about to start falling apart.

You're missing the point. I'm merely stating facts and figures. For me to say that following 2012's daily behavior from here on would not result in beating that year's record minimum is neither "rhetoric" nor "optimism"; it's just telling it like it is. As to whether it's "LOLworthy" I'll leave up to the individual; I guess some people are just more easily amused. 

You are not stating a helpful fact, it is like saying if you start at 2 you can count quicker to 10 than if you start at 1 -- duh... not insightful whatsoever and does not further discourse, esp. when, IMO, you seem to be minimizing the impacts of the melt this yr.

[bbr2314]

...back to sea ice, we are starting to see firmer evidence that the entire Arctic ice mass is now cleaving in two, which would be unprecedented.





It seems that the losses directly adjacent to the Russian side keep filtering SE/SW as the ice gets pushed and pulled. Meanwhile, the reversal in the Beaufort Gyre is now pushing open water directly towards the same area (although even when it runs normally, you still have weakness pushing into the same area from the other direction).

Meanwhile, the crazy FRAM export has allowed large fissures to develop in the departing wake of the main CAB ice.

This did not happen in 2012!

[magnamentis]

sometimes it's important to consider the exact order of the events. the statement you criticize was the REPLY after someone questioned a post that simply stated obvious facts, like a color blind questioning that i see green and then when i say; but you're color blind, someone else would say, but that's not nice [shake head]

it's certainly never wrong to state the obvious and it's certainly legit to get a bit annoyed if people who don't think before they write are starting to question the obvious in a, to a certain degree, condescending manner.

and then if someone is known to provide perfect and valuable information for all of us it's perhaps one more good reason to read and consider very carefully before shooting away. at least my generation was raised to way to show a bit of extra respect towards the elderly (more experienced) members of a society.

over and out

[bbr2314]

sometimes it's important to consider the exact order of the events. the statement you criticize was the REPLY after someone questioned a post that simply stated obvious facts, like a color blind questioning that i see green and then when i say; but you're color blind, someone else would say, but that's not nice [shake head]

it's certainly never wrong to state the obvious and it's certainly legit to get a bit annoyed if people who don't think before they write are starting to question the obvious in a, to a certain degree, condescending manner.

and then if someone is known to provide perfect and valuable information for all of us it's perhaps one more good reason to read and consider very carefully before shooting away. at least my generation was raised to way to show a bit of extra respect towards the elderly (more experienced) members of a society.

over and out

The elderly have destroyed this planet with no regard for young people. Baby boomers may single handedly rank amongst the devastating events this planet has ever experienced. So I don't think that automatically kow-towing to someone bc they are older and probably uninformed is sensible, but that is just me.

You can compare the change in HYCOM over the past two weeks. The pack is clearly breaking up entirely.

Maybe if Baby Boomers hadn't been so blindly selfish we wouldn't be witnessing what's about to unfold. No matter, but most definite proof that age does not automatically merit respect.

[seaicesailor]

The elderly have destroyed this planet with no regard for young people. Baby boomers may single handedly rank amongst the devastating events this planet has ever experienced. So I don't think that automatically kow-towing to someone bc they are older and probably uninformed is sensible, but that is just me.
...
Maybe if Baby Boomers hadn't been so blindly selfish we wouldn't be witnessing what's about to unfold. No matter, but most definite proof that age does not automatically merit respect.

After saying that posts based on feelings should be banned you go and vomit this out... why don't you ban yourself?
over and out

[bbr2314]

The elderly have destroyed this planet with no regard for young people. Baby boomers may single handedly rank amongst the devastating events this planet has ever experienced. So I don't think that automatically kow-towing to someone bc they are older and probably uninformed is sensible, but that is just me.
...
Maybe if Baby Boomers hadn't been so blindly selfish we wouldn't be witnessing what's about to unfold. No matter, but most definite proof that age does not automatically merit respect.

After saying that posts based on feelings should be banned you go and vomit this out... why don't you ban yourself?
over and out

That is not a feeling it is a fact

[Neven]

That is not a feeling it is a fact

Nope, it is a feeling/opinion. And if it were a fact, it would lack nuance and context.

Could you turn the anger and alarmism a notch down, please? The entire Arctic ice mass is not going to cleave in two.

[magnamentis]

The elderly have destroyed this planet with no regard for young people.

but you remember who we were talking about, about "jim" so this is not only inappropriate but out of context as well. as far as i know there is perfect thread where i will gladly hold the mirror.

http://forum.arctic-sea-ice.net/index.php/topic,1548.msg79951.html#msg79951

[DavidR]

This marks the first time in 103 days--since 12 February--that 2016 SIA has been above 2012....  if 2016 were to precisely follow 2012's daily trajectory from now until mid-September--complete with the remainder of that year's steep June cliff...

(Averages below are based on the past 10 years)
It  is worth noting that the 2012 decline from now to the end of the month is only slightly above average compared to the last 10 years. Three years had greater declines in area and four years had greater declines in extent. For July, 2012 was only 60K km^2 above average in both measures and beaten by 2015, and others.

Although it will be hard for 2016 to  keep pace with 2012 for area over the next 5 days, an average decline over the next 8 will see 2016 ahead again. 

Both IJIS and NSIDC extent are well below 2012 levels and will probably not be caught for some time.

[Jim Pettit]

Although it will be hard for 2016 to  keep pace with 2012 for area over the next 5 days, an average decline over the next 8 will see 2016 ahead again.

Over the next 21 days, 2012 area dropped by 2.34 Million km2, a sustained average of 111k per day. So while it's very possible that 2016 will retake first and hold it for awhile, I've not seen anything in the forecast to suggest that will happen. The average June-to-date daily drop has so far been a sluggish 66k; what's going to push a near doubling of that?

Both IJIS and NSIDC extent are well below 2012 levels and will probably not be caught for some time.

I suppose it depends on how one defines "well below", but thanks to closing the 2016-2012 gap by 627k over the past six days, the latter is now breathing strongly down the neck of the former where IJIS extent is concerned. And with 2012 having fallen an additional 177k over the next two days, while 2016 has averaged a daily drop of just 25k so far this month, I suspect the difference will practically vanish over the next five days or so.  Of course, as you've noted, after that 2012's trajectory became more normal for several week; that year didn't move into and hold first place until the end of July, so there's still a great chance that will happen.

(I know a few people haven't been pleased with some of the figures I've been posting, but I'm simply stating facts. And the fact is, 2016's enormous lead over 2012--higher than a million square kilometers at some points--has for all intents and purposes gone away over the past ten days. That doesn't mean it's permanent. But it is what's happening.)

[Wipneus]

The spirit seems to be out of the melting, judging by the total Arctic numbers.

Here is the shadow CT-area report (based on F18 NSIDC sea ice concentration data, we don't know if it is calibrated):

day  CT-date       NH               SH                Global
Sun 2016.4411 -146.0  8.549799 +168.8 10.322178   +22.8 18.871977
Mon 2016.4438 +100.3  8.650090 +114.7 10.436848  +215.0 19.086938
Tue 2016.4466  -81.5  8.568613 +187.6 10.624465  +106.1 19.193078
Wed 2016.4493   +7.7  8.576314 +104.0 10.728515  +111.8 19.304829

That is mostly caused by the CAA (+28k). The decline in Chukchi (-19k) is not enough.

Shadow NSIDC extent is 10.7191 an increase of +20.8k. Here is no particular region responsible, Kara declined -18k and many others had little plus'es.

The attached deltamap shows something similar as the melting graphs in the "home brew" thread: melting shifts from ESS to Chukchi and Beaufort.

[Wipneus]

Declining moderate rates for this time of year.

Here is the shadow CT-area report (based on F18 NSIDC sea ice concentration data, we don't know if it is calibrated):

day  CT-date       NH               SH                Global
Mon 2016.4438 +100.3  8.650090 +168.8 10.322178  +269.1 18.972268
Tue 2016.4466  -81.5  8.568613 +114.7 10.436848   +33.2 19.005461
Wed 2016.4493   +7.8  8.576390 +187.6 10.624465  +195.4 19.200855
Thu 2016.4521  -57.0  8.519380 +104.0 10.728515   +47.0 19.247895

The area decline is inflated by a big drop in "lake ice" (probably false, in any case not relevant) which dropped -24k. Recoveries by ESS (+25k), Laptev (+20k) and CAB (+13k). Declines in CAA (-33k), Hudson (-20k) and Greenland Sea (-20k).

NSIDC extent is now 10.6571 dropping  -62.6k. Hudson and Kara lost each about -20k.

The attached delta map shows another way where the day-to-day changes were.

[Steven]

Thu 2016.4521  ...  8.519380

(Assuming it is calibrated:)  This is about 315k km² above the 2012 value for this date, and about 225 to 335 k km² below the 2007/2010/2011 values for this date:

[Jim Pettit]

ADS-NIPR Extent:

10,054,193 km2 (14 June)

Down 3,888,314 km2 (27.89%) from 2016 maximum of 13,942,507 km2 on 29 February.

6,876,738 km2 above record minimum extent of 3,177,455 km2 (16 September 2012).

Down 46,444 km2 (-.46%) from previous day.

Down 243,619 km2  (-2.37%) over past seven days (daily average: -34,803 km2).

Down 372,851 km2  (-3.05%) for June (daily average: -26,632 km2).

963,085 km2 below 2000s average for this date.

329,237 km2 below 2010s average for this date.

283,058 km2 below 2015 value for this date.

110,925 km2 below 2012 value for this date.

1st lowest year-to-date (01 January - 14 June) average.

1st lowest June to-date average.

1st lowest value for the date.

111 days this year (67.27% year-to-date) have recorded the lowest daily extent.

27 days (16.36%) have recorded the second lowest.

14 days (8.48%) have recorded the third lowest.

152 days in total (92.12%) have been among the lowest three on record.

CT Area:

8,519,380 km2 (15 June [Day 0.452])

Down 4,401,978 km2 (34.07%) from 2016 maximum of 12,921,358 km2 on 29 March [Day 0.2384].

6,285,371 km2 above record minimum area of 2,234,010 km2 (14 September 2012).

Down 57,010 km2 (-.66%) from previous day.

Down 370,061 km2 (-4.19%) over past seven days (daily average: -52,866 km2).

Down 911,674 km2 (-8.19%) for June (daily average: -60,778 km2).

905,640 km2 below 2000s average for this date.

280,799 km2 below 2010s average for this date.

467,061 km2 below 2015 value for this date.

315,435 km2 above 2012 value for this date.

2nd lowest value for the date.

At least 138* days in total have been among the lowest three on record.

* - NOTE: due to the prolonged absence of official CT sea ice area data, I've incorporated Wipneus' area numbers as calculated from NSIDC data. The official numbers will be inserted if/when available. In the meantime, thanks, Wipneus!

[Wipneus]

NSIDC has decided the F18 data are calibrated now:

After investigating the difference in ice extent as the algorithm tie points were varied, it was found that the current F17 tie points provided the best match in sea ice extent for the overlap period, so no adjustment in algorithm parameters was needed for F18.

I continue with the shadow numbers because CT has not picked the data up yet and adding the NSIDC extent data seems natural.

Here is the shadow CT-area report (based on F18 NSIDC sea ice concentration data that we now know are calibrated):

day  CT-date       NH               SH                Global
Tue 2016.4466  -81.5  8.568613 +114.7 10.436848   +33.2 19.005461
Wed 2016.4493   +7.8  8.576390 +187.6 10.624465  +195.4 19.200855
Thu 2016.4521  -57.1  8.519276 +104.3 10.728776   +47.2 19.248052
Fri 2016.4548 -108.1  8.411184  +52.5 10.781235   -55.6 19.192419

Century drop, with Hudson, CAA, Greenland Sea and CAB big contributors (-36k, -30k, -29k, -20k),
NSIDC ended at 10.5735 down -83.6k. Baffin championed het (-31k).

The attached delta map shows it all.