2018 sea ice area and extent data

[uniquorn]

maintenance

[Neven]

They should get an award for best maintained system in the universe! 

[gerontocrat]

NSIDC Total Area as at 17 September (5 day trailing average) = 3,254,871 km2

This is down to 49 k above 2010-2017 and 4k less than 2017 for this date

4 days of gain in a row, this day's substantial. I think that maybe the melting season is done (on this measure - not necessarily on extent)

Total Area GAIN 22 k ,

Central Seas GAIN     20 k,                                 
Peripheral Seas gain    2 k, all seas <5% of max.
Other Seas loss           0 k, all seas <5% of max.

Analysis of individual seas.
Pacific Side
- The Bering Sea - finished,
- Chukchi Sea loss 2 k, area 13 k, < 5% of max.
Atlantic Side
- Baffin Sea loss 0 k, area 23 k, <5% of max,
- Greenland Sea gain 2 k km2 , area 58 k,
- Barents Sea - finished,
- The Kara Sea area loss 0 k, area 28 k, < 5% of maximum.
- The Laptev Sea area gain 0 k, area 16 k, <5% of maximum.

CAB
- Beaufort Sea gain 14 k,
- The Canadian Archipelago gain 3 k,
- East Siberian Sea loss 5 k .
- The Central Arctic Sea gain 10 k

Other seas
- St Lawrence -finished,
- Hudson Bay area loss 0 k, Area  5 k,
- The Okhotsk Sea - finished .

The season is nearly over. Nowt to do but watch day by day to see which seas still melt (currently the Chukchi and ESS), and which gain. There may be more surprises.

[Stephan]

ESS is still losing ice day by day by day. I wonder how low it will get until re-freezing also starts in that area...

[magnamentis]

They should get an award for best maintained system in the universe! 

not only that, if i had the time i'd make a list of exactly when they maintain, always around key dates and events. today i wanted to know whether we made it throught 4.5, pustekuchen LOL

[magnamentis]

ESS is still losing ice day by day by day. I wonder how low it will get until re-freezing also starts in that area...

as long as it's blowing and warm as that it won't refreeze. winds are predicted to shift a few degrees and abate to average levels but then it will take some time with all the warm mixed waters around i could imagine, let's see.

[Juan C. García]

2 hours after the usual time and ADS-NIPR (JAXA) has not update the values… 
Is the server working properly?

[zufall]

https://ads.nipr.ac.jp/vishop/#/extent

Sep 17 extent: 4,491,419 km2
Sep 18 extent: 4,501,564 km2

[Brigantine]

Reading off the graph:

Sept 17: 4.49M
Sept 18: 4.50M

I don't know how to get the exact figures... but our 2018 minimum is in the 4.25-4.50 bin and is now into 7th place.
(below 2008's minimum)

[Phil42]

September 17th: 4'491'419km², a decrease of -22'092km².

As Brigantine mentioned, this is the new 2018 minimum, ranking as 7th lowest after overtaking 2008's minimum (and 19'194km² above 2017's minimum).


September 18th: 4'501'564km², an increase of 10'145km².

Extent is now below 2015 and back down to 5th place. I'm sure Juan and gerontocrat will provide more insight, I'm just filling the spot here with Brigantine because of the data delay.

[gerontocrat]

JAXA ARCTIC EXTENT 4,501,564 km2（September 18, 2018）
                                    4,491,419 km2（September 17, 2018）- the current minimum

Just to add to the post Juan wishes he had been able to make ( Juan - sleep is a luxury, ASIF posts are more important) -

< 4.5 million km2 - Some pollsters cry, some others smirk

- Extent is now 57 k km2  (1.3 %) above the 2010's average extent and 92 k (1.1%) below 2017 on this date (2018 extent loss & 2017 extent gain on the day).
- It is a new minimum (4.49 million km2).

All spreadsheets have their limitations. You will see from the first table attached that my spreadsheet has reached its limit as regards any projections of the 2018 minimum.

Any more surprises in store? It ain't over 'til its over

[gerontocrat]

NSIDC Total Area as at 18 September (5 day trailing average) = 3,294,009 km2

This is up to 63 k above 2010-2017 and 62 k less than 2017 for this date

5 days of gain in a row, the day's substantial. I think that the melting season is done on this measure - minimum of  3,199,720 km2 on 13th September, 167k above 2017.

Total Area GAIN 39 k ,

Central Seas GAIN     35 k,                                 
Peripheral Seas gain    4 k, all seas <5% of max.
Other Seas loss           0 k, all seas <5% of max.

Analysis of individual seas.
Pacific Side
- The Bering Sea - finished,
- Chukchi Sea loss 2 k, area 11 k, < 5% of max.
Atlantic Side
- Baffin Sea loss 0 k, area 23 k, <5% of max,
- Greenland Sea gain 2 k km2 , area 62 k,
- Barents Sea - finished,
- The Kara Sea area gain 1 k, area 29 k, < 5% of maximum.
- The Laptev Sea area gain 1 k, area 17 k, <5% of maximum.

CAB
- Beaufort Sea gain 15 k,
- The Canadian Archipelago gain 5 k,
- East Siberian Sea loss 8 k .
- The Central Arctic Sea gain 22 k

Other seas
- St Lawrence - gain 0k,
- Hudson Bay area loss 0 k, Area  6 k,
- The Okhotsk Sea - gain 0k .

The season is over ?. Nowt to do but watch day by day to see which seas still melt (currently the Chukchi and ESS), and which gain. There may be more surprises.

The frequency of these postings can no longer be daily - probably every 4 days after tomorrow, unless something major happens. (Other commitments)

[gerontocrat]

The last two seas still losing area - Chukchi & ESS

[Juan C. García]

[ADS-NIPR-JAXA] ASI Extent.

September 17^th, 2018: 4,491,419 km², a drop of -22,092 km².
2018 is the 6^th lowest on record.

September 18^th, 2018: 4,501,564 km², an increase of 10,145 km².
2018 is the 5^th lowest on record.

[Juan C. García]

[ADS-NIPR-JAXA] ASI Extent.

September 19^th, 2018: 4,499,697 km², a drop of -1,867 km².
On this day, 2018 is the 5^th lowest on record.

[gerontocrat]

JAXA ARCTIC EXTENT 4,499,697 km2（September 19, 2018）

Just to add to Juan's post -

Extent is now
- just 8k above the current minimum on 17th September,
- 22 k  (0.5 %) above the 2010's average extent and 87 k (1.1%) below 2017 on this date.

You will see from the first table attached that my spreadsheet has reached its limit as regards any projections of the 2018 minimum, as by this date all the previous 10 years were in the freezing season.

Any more surprises in store? It ain't over 'til its over
[/quote]

[gerontocrat]

NSIDC Total Area as at 19 September (5 day trailing average) = 3,323,029 km2

This is up to 75 k above 2010-2017 and 50 k less than 2017 for this date

5 days of gain in a row, area now 123k above the current minimum of  3,199,720 km2 on 13th September, which is 167k above the 2017 minimum.

Total Area GAIN 29 k ,

Central Seas GAIN     26 k,                                 
Peripheral Seas gain    2 k, all seas <5% of max.
Other Seas loss           0 k, all seas <5% of max.

Analysis of individual seas.
Pacific Side
- The Bering Sea - no change,
- Chukchi Sea loss 1 k, area 10 k, < 5% of max.
Atlantic Side
- Baffin Sea gain 1 k, area 24 k, <5% of max,
- Greenland Sea gain 2 k km2 , area 63 k,
- Barents Sea - gain 0 k,
- The Kara Sea area loss 1 k, area 29 k, < 5% of maximum.
- The Laptev Sea area gain 0 k, area 17 k, <5% of maximum.

CAB
- Beaufort Sea gain 14 k,
- The Canadian Archipelago gain 8 k,
- East Siberian Sea loss 9 k .
- The Central Arctic Sea gain 16 k

Other seas
- St Lawrence - gain 0k,
- Hudson Bay area loss 0 k, Area  6 k,
- The Okhotsk Sea - gain 0k .

The season is over ? I could find no year in which this measure of area declined from this date. Nowt to do but watch day by day to see which seas still melt (currently only the Chukchi and ESS), and which gain. There may be more surprises - daily extent dropped a bit.

[gerontocrat]

Again here are the graphs of the two seas still losing area. The area is low, but not a record low in either sea.
 

[be cause]

... yet it seems like against all the evidence , we are still in the melting season .. b.c.

[gerontocrat]

A longer look at 2018 (and before)
All based on Area data fro NSIDC
I am so transfixed by daily changes that it took an effort of will, now that the melting season for area data looks over, to tell myself to have a look at the year to date (and before). This series of posts will look at area sea by sea.
______________________________________________________________________
The Bering Sea
2018 was a slow melting season, but not in this sea. Area was a record daily low for 162 days out of 175 until area reached zero in other seas.

Looking back, this sea was remarkably stable from year to year from 1980 to 2011, when suddenly, in 2012 winter sea ice increased, March open water dropped from 60+% to less than 30% of the sea's area. Since that date winter sea ice has collapsed, March open water increasing to about 85% in 2018.

Is this permanent? One to watch in the 2018-19 freezing season.

[gerontocrat]

... yet it seems like against all the evidence , we are still in the melting season .. b.c.

Which is why I qualified my statement to say "on this measure" (i.e. 5-day trailing average area)

[gerontocrat]

A longer look at 2018 (and before)
All based on Area data fro NSIDC
I am so transfixed by daily changes that it took an effort of will, now that the melting season for area data looks over, to tell myself to have a look at the year to date (and before). This series of posts will look at area sea by sea.
______________________________________________________________________
Post No #2 - The Chukchi Sea
2018
The Bering Sea, though it lost most of its winter sea ice, still at least partially plugged the entrance to the Arctic Ocean. 

The Chukchi winter sea ice was lower in March, but this looks a temporary effect due to the extreme end of February warming event. But once the Bering strait was open, melt was above average until early June, and from then average.

Now a late season melt has taken area to below the 2010's average. SST anomalies are high, will freeze be delayed and / or slow ?
Trend
There is a consistent trend to a sea just about totally ice-free in summer, and for longer periods.
As yet, winter sea ice is only marginally affected.

[Juan C. García]

[ADS-NIPR-JAXA] ASI Extent.

September 20^th, 2018: 4,473,457 km², a drop of -26,240 km².   
On this day, 2018 is the 4^th lowest on record (and close to be the 3^rd tomorrow?  ).

2018 is still the seventh yearly mínimum on record, with a difference of only 1,232 km² against 2017, that is the sixth minimum on record.

[gerontocrat]

JAXA ARCTIC EXTENT 4,473,457 km2（September 20, 2018）

Entering uncharted waters? Just when I thought I could reduce my posts.

Just to add to Juan's post -

Extent is now -
- a new current minimum, 18k below the previous one on 17th September,
- 50 k  (0.5 %) below the 2010's average extent,
- 172 k (3.8 %) below 2017 on this date.

One has to go back to 2004 (minimum on 21st September) for a minimum on as late a date as this. You will see from the first table attached that my spreadsheet has reached its limit as regards any projections of the 2018 minimum, as by this date all the previous 10 years were in the freezing season. Indeed by now, the average (10 years) INCREASE in extent from minimum on this date was 189k.

Any more surprises in store? It ain't over 'til its over

ps: Neven may justifiably be feeling smug for having locked the 2018-19 freezing thread.

[Brigantine]

I'm curious where compactness is up to right about now. What happened to that graph?

[Neven]

ps: Neven may justifiably be feeling smug for having locked the 2018-19 freezing thread.

 

2018 is still the seventh yearly mínimum on record, with a difference of only 1,232 km² against 2017, that is the sixth minimum on record.

I have the JAXA SIE minimum for 2017 at 4.473157 km2, ie 300 km2 lower than 2018. Has the data changed?

I'm curious where compactness is up to right about now. What happened to that graph?

I didn't have time on my holiday to update it. I'll see if I can do it later today.

[gerontocrat]

When this happens to me (frequently) I give myself permission to use an impolite word (or three).

Thanks, I have just used them too. 

[Neven]

I'm curious where compactness is up to right about now. What happened to that graph?

There you go:

[sinocentric]

only about 1,000k more than 2017? Wow, a nailbiter in the Anthropocene, haha.

[gerontocrat]

NSIDC Total Area as at 20 September (5 day trailing average) = 3,333,876 km2


Doing this daily post as daily extent dropped by 61k and JAXA extent is at a new yearly minimum by 18k on this day. But limiting analyis to seas losing ice area.

Total Area GAIN 11 k ,

Central Seas GAIN      7 k,                                 
Peripheral Seas gain    4 k, all seas <5% of max.
Other Seas loss           0 k, all seas <5% of max.


Chukchi Sea loss 1.5 k, area 8.5 k, < 5% of max.

- East Siberian Sea loss 13 k .

NSIDC Daily Extent 5.579 million km2, just 26k above the current minimum on 16th September.

[gerontocrat]

The ESS continues its impressive end of season melt

[Juan C. García]

2018 is still the seventh yearly mínimum on record, with a difference of only 1,232 km² against 2017, that is the sixth minimum on record.

I have the JAXA SIE minimum for 2017 at 4.473157 km2, ie 300 km2 lower than 2018. Has the data changed?

I don´t find the "300 km2 lower". This is the table that I have, with differences versus 2018:

[Stephan]

NSIDC Total Area as at 20 September (5 day trailing average) = 3,333,876 km2


Doing this daily post as daily extent dropped by 61k and JAXA extent is at a new yearly minimum by 18k on this day. But limiting analyis to seas losing ice area.

Total Area GAIN 11 k ,

Central Seas GAIN      7 k,                                 
Peripheral Seas gain    4 k, all seas <5% of max.
Other Seas loss           0 k, all seas <5% of max.


Chukchi Sea loss 1.5 k, area 8.5 k, < 5% of max.

- East Siberian Sea loss 13 k .

NSIDC Daily Extent 5.579 million km2, just 26k above the current minimum on 16th September.

Chukchi Sea has lost 15 % of its ice this day (if there is any ice at all, see Bering and Barents for example) and ESS has lost almost 10 % of its ice this day. It is almost late September - will the ice in these two seas go down for maybe another week??

[Cid_Yama]

Bremen shows 2018 third lowest behind 2016 (barely) and 2012.

 https://seaice.uni-bremen.de/data/amsr2/today/extent_n_running_mean_amsr2_regular.png

https://seaice.uni-bremen.de/data/amsr2/today/extent_n_running_mean_amsr2_previous.png

2nd lowest for this date, as 2016 was already on it's way up by this date.

[Neven]

I don´t find the "300 km2 lower". This is the table that I have, with differences versus 2018:

Thanks, gerontocrat had already pointed out my mistake (I got the 2017 minimum wrong).

[Ninebelowzero]

Took this loop off (to paraphrase Col. O'Neill) but coming back it's nice to see graphs with the current year Jaxa plot superimposed over the decadal plots but does the shape of the current year plots indicate a delayed refreeze this year in some areas or Arcticwide?

[jdallen]

The ESS continues its impressive end of season melt

It's doing what I expected it to do at the end of August; just took a couple weeks longer.

[Brigantine]

I'm curious where compactness is up to right about now. What happened to that graph?

There you go:

Quite middle of the pack still. I'd been expecting it to be higher. Thanks for the recalibration 

CAB high, ESS low... but every year will have high regions and low regions somewhere or other.

[DavidR]

The ESS continues its impressive end of season melt

I think its time to put the 0 line back in this graph before the 2018  line drops off the graph

[Juan C. García]

[ADS-NIPR-JAXA] ASI Extent.

September 21^th, 2018: 4,457,252 km², a drop of -16,205 km².
On this day, 2018 is the 3^rd lowest on record.

2018 is now the sixth yearly mínimum on record.


PS: I am going to be traveling until Tuesday (UTC time), so I am not sure that I will post on the following 3 days.

[gerontocrat]

JAXA ARCTIC EXTENT 4,457,252 km2（September 21, 2018）

Entering uncharted waters, or just a temporary blip? Just when I thought I could reduce my posts.

Just to add to Juan's post -

Extent is now -
- a new minimum for the year, 16k below the previous one on 20 September,
- 101 k  (2.3 %) below the 2010's average extent on this date, (but 90k above the 2010's average minimum),
- 224 k (5.0 %) below 2017 on this date.

One has to go back to 2004 (minimum on 21st September) for a minimum on as late a date as this. You will see from the first table attached that my spreadsheet has reached its limit as regards any projections of the 2018 minimum, as by this date all the previous 10 years were in the freezing season. Indeed by now, the average (10 years) INCREASE in extent from minimum on this date was 222 k.

Any more surprises in store? It ain't over 'til its over

ps: Neven may justifiably be feeling even more smug for having locked the 2018-19 freezing thread.

[gerontocrat]

NSIDC Total Area as at 21 September (5 day trailing average) = 3,342,656 km2

Doing this daily post as daily extent dropped and JAXA extent is at a new yearly minimum by 18k on this day. But limiting analyis to seas losing ice area.

Total Area GAIN 9 k ,

Central Seas GAIN      6 k,                                 
Peripheral Seas gain    3 k,
Other Seas loss           0 k, all seas <5% of max.

Chukchi Sea loss 2 k, area 7 k[/b], < 5% of max.
East Siberian Sea (ESS) loss 13 k , area 105k

ESS graph attached

NSIDC Daily Extent 4.564 million km2, just 11k above the current minimum of 4.553 million km2 on the 16th September.

[Stephan]

Chukchi Sea has lost 20 % of its ice this day (if there is any ice at all, see Bering and Barents for example) and ESS has lost almost 12 % of its ice this day. It is late September - will the ice in these two seas go down for maybe another week??

[zufall]

https://ads.nipr.ac.jp/vishop/#/extent

Sep 22 extent: 4,485,254 km2, up 28,002 km2.

[Stephan]

This is the third lowest on record, being behind 2012 (lowest) and 2007 (second lowest).
Compared to the two previous years Sep 22 2018 has 0.21 mio. km² less ice than Sep 22, 2017 and 0.12 mio. km² less ice than Sep 22, 2016.
The highest value of the 2010s on this date were 2013 (5.00) and 2014 (5.04 mio km²)

[gerontocrat]

JAXA ARCTIC EXTENT 4,485,254 km2（September 22, 2018）

Just to add to Juan's post that did not happen -

Extent is now -
- 107 k  (2.4 %) below the 2010's average extent on this date,
- 216 k (4.8 %) below 2017 on this date.
- by now, the average (10 years) INCREASE in extent from minimum on this date was 222 k.

The table looking at outcomes for the minimum is defunct, no longer extant. Instead, the first table looks at outcomes for next year's maximum. It assumes that the 2018 minimum was on 21st September.

Happy equinox

[gerontocrat]

NSIDC Total Area as at 21 September (5 day trailing average) =  3,348,067 km2


Slow area gain, so area now just 38k > 2017.

Total Area GAIN 5 k ,

Central Seas GAIN      3 k,                                 
Peripheral Seas gain    3 k,
Other Seas loss           0 k, all seas <5% of max.

Chukchi Sea loss 1.7 k, area 5.0 k[/b], < 5% of max.
East Siberian Sea (ESS) loss 8 k , area 96 k.

NSIDC Daily Extent 4.567 million km2, just 14k above the current minimum of 4.553 million km2 on the 16th September.
[/quote]

Thanks, Brigantine for picking up my latest typo. But what matters a million km2 here and there ?

[gerontocrat]

Chukchi and ESS graphs attached.

The ESS Area is 96k, extent is 275K. Very fragmented ice?

[Pmt111500]

Chukchi and ESS graphs attached.

The ESS Area is 96k, extent is 275K. Very fragmented ice?

Could still go all the way to zero with a late warm spell.

[Stephan]

Again a relatively huge loss in Chukchi Sea. It has lost 25 % of its ice this day (with this pace it'll be gone by this week completely) and ESS has lost 8 % of its ice this day. It is late September - will the ice in these two seas go down for maybe this whole week??