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Arctic Sea Ice Extent, Area, and Volume


ORH_wxman
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3 hours ago, ORH_wxman said:

IMS is a deferent source than JAXA or NSIDC and it looks like that graph doesn't have any data beyond late July. 

Well...be that as it may, the graphical presentation being perhaps a week behind other sources...

The dailies depict illustrations that clearly still put 2019 ahead of 2012 as of August 8 from the same source as that graph.   one, it will be interesting to see the graph update... heh.. But two, I've annotated and it's pretty clearly obvious ...if said graph is based upon anything resembling these [crude] cartoons...  it's just as likely to update still below the 2012 curve..

 

image.thumb.png.f627c122765e6320d59d62b938943ec4.png

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3 hours ago, lookingnorth said:

When I go to the NSIDC website I get different numbers that are higher for both years so I'm confused. I'm using the Charctic tool to view the data.

That tool on NSIDC uses the 5 day running mean instead of daily values. 

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Large 131k daily drop on NSIDC extent. So 2019 is only 171k behind 2012. We are past the record breaking 2012 fall during the Great Arctic Cyclone. 2019 needs a 119k daily decline  rate next two days to pull back even with 2012 by the 11th.

The NSIDC charts use a five-day trailing average. The daily extent figures are found in the spreadsheet section under the chart.

https://nsidc.org/arcticseaicenews/sea-ice-tools/

NSIDC extent

   Date....2012......2019....2019 difference 

8-4......5.990.... .5.762.....+228k lead 

8-5......5.768......5.596.....+172k lead

8-6......5.632......5.510......+122k lead

8-7......5.467......5.388......+79k lead

8-8......5.256.....5.390......-134k behind

8-9......5.088......5.259......-171k behind

8-10....5.118

8-11....5.021

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Very large daily NSIDC decline of 166k puts 2019 back in a narrow lead over 2012 by +25k.

ftp://sidads.colorado.edu/DATASETS/NOAA/G02135/seaice_analysis/Sea_Ice_Index_Daily_Extent_G02135_v3.0.xlsx

NSIDC extent

   Date....2012......2019....2019 difference 

8-4......5.990.... .5.762.....+228k lead 

8-5......5.768......5.596.....+172k lead

 8-6......5.632......5.510......+122k lead

8-7......5.467......5.388......+79k lead

8-8......5.256.....5.390......-134k behind

8-9......5.088......5.259......-171k behind

 8-10....5.118......5.093......+25k ahead

8-11....5.021


 

 

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Small daily rise in NSIDC extent of 19k. This puts 2019 behind 2012 by -92k as of the 11th.

NSIDC extent

   Date....2012......2019....2019 difference 

 8-4......5.990.... .5.762.....+228k lead 

8-5......5.768......5.596.....+172k lead

 8-6......5.632......5.510......+122k lead

 8-7......5.467......5.388......+79k lead

8-8......5.256.....5.390......-134k behind

8-9......5.088......5.259......-171k behind

 8-10....5.118......5.093......+25k ahead

 8-11....5.021......5.113.......-92k behind

8-12.....4.938

8-13.....4.889

8-14.....4.724

8-15.....4.679

8-16.....4.619

8-17.....4.545

8-18.....4.520

8-19.....4.405

8-20.....4.313

B6593FE3-6381-4A89-A817-FAEA891338EF.png.42e59fd36e8166e559806d51027b6096.png

 
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Bluewave hasn't updated for today, so I'll mention that it looks like 2019 is having a bit of trouble falling below 5 million on the extent value.

NSIDC extent

Date.....2012......2019........2019 difference 

8-4.......5.990.... .5.762.....+228k lead 

8-5.......5.768......5.596.....+172k lead

8-6.......5.632......5.510......+122k lead

8-7.......5.467......5.388......+79k lead

8-8.......5.256.....5.390......-134k behind

8-9.......5.088......5.259......-171k behind

8-10.....5.118......5.093......+25k ahead

8-11.....5.021......5.113.......-92k behind

8-12.....4.938......5.063.......-125k behind

8-13.....4.889

8-14.....4.724

8-15.....4.679

8-16.....4.619

8-17.....4.545

8-18.....4.520

8-19.....4.405

8-20.....4.313

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Free fall...

The vector of the current NSIDC graph has now fallen below all curves since 1998 like I ship headed for the open sea -

Yeah feedbacks are kicking in hard. It’s like when all the ice melts in your cooler and the the water warms up quickly.

 

 

 

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97k daily decline for NSIDC extent. This places 2019 only 77k behind 2012 as of 8-13. Models indicate a continuation of the record breaking high pressure regime over the Arctic since May. Surface pressures are forecast to exceed 1040 mb around the Chukchi Sea region next 3-4 days. This would be at record levels for this time of year.

ftp://sidads.colorado.edu/DATASETS/NOAA/G02135/seaice_analysis/Sea_Ice_Index_Daily_Extent_G02135_v3.0.xlsx

.............2012......2019

8-13.....4.889......4.966.....77k behind

8-14.....4.724

8-15.....4.679

8-16.....4.619

8-17.....4.545

8-18.....4.520

8-19.....4.405

8-20.....4.313

EEB00D27-F168-4AD0-9C0E-B3E0034521AF.thumb.png.496d9e989a3290b0f2a64a238847e435.png

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On 7/1/2019 at 8:49 AM, Weatherdude88 said:

Despite all of the hyperbole and wish casting, 2019 will not be in the top 3 lowest sea ice minimums on record in area or extent. We may not end up in the top 5 in a sea ice area metric (looking at UH AMSR2 and NSIDC daily data and extrapolating).

The regions that will matter at the end of the 2019 melt season are the Central Arctic Basin, East Siberian sea, Beautfort sea, Greenland sea, and Canadian Archipelago.

For the most part, we are lagging the highest melt years in these regions (There are 5 years that lead 2019 in all these areas combined). 

There is too much high latitude ice in the critical regions. All the subjective interpretation of data will not translate to reality, no matter how many members reiterate it.

By the end of the first week of August, it will become evident that 2019 will be ordinary, as it relates to sea ice minimums over the last decade.

wdxQqA2.png

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VzLU4wP.png

36FecQf.png

 

haha

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NSIDC daily extent holding steady on the 14th allowed 2019 to fall behind 2012 by 246k. But the area was able to move closer to 2012 than it has been over the last week.

ftp://sidads.colorado.edu/DATASETS/NOAA/G02135/seaice_analysis/Sea_Ice_Index_Daily_Extent_G02135_v3.0.xlsx

.............2012......2019

8-13.....4.889......4.966.....77k behind

8-14.....4.724......4.970.....246k behind

 8-15.....4.679

 8-16.....4.619

8-17.....4.545

8-18.....4.520

8-19.....4.405

 8-20.....4.313

NSIDC area

https://cryospherecomputing.tk/

16E2FFDD-C0DE-4689-BD66-D6F999340757.png.0d929ea5a24fa9e2c3378fdf70ce98f7.png

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5 hours ago, bluewave said:

NSIDC daily extent holding steady on the 14th allowed 2019 to fall behind 2012 by 246k. But the area was able to move closer to 2012 than it has been over the last week.

ftp://sidads.colorado.edu/DATASETS/NOAA/G02135/seaice_analysis/Sea_Ice_Index_Daily_Extent_G02135_v3.0.xlsx

.............2012......2019

8-13.....4.889......4.966.....77k behind

8-14.....4.724......4.970.....246k behind

 8-15.....4.679

 8-16.....4.619

8-17.....4.545

8-18.....4.520

8-19.....4.405

 8-20.....4.313

NSIDC area

https://cryospherecomputing.tk/

16E2FFDD-C0DE-4689-BD66-D6F999340757.png.0d929ea5a24fa9e2c3378fdf70ce98f7.png

Yeah that IMS chart post just updated as of the 11th and looks nothing like that - interesting

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Loss rate has slowed enough last few days for NSIDC extent to fall behind 2012 by 242k as of 8-15.

.............2012......2019

 8-13.....4.889......4.966.....77k behind

8-14.....4.724......4.970.....246k behind

 8-15....4.679......4.921.....242k behind

 8-16....4.619

8-17.....4.545

8-18.....4.520

8-19.....4.405

 8-20.....4.313

NSIDC updated their projection for the September minimum. They are now calling for a 2nd place finish behind 2012.

https://nsidc.org/arcticseaicenews/2019/08/dead-heat/

The ASINA team conducted a revised analysis of the likely course of the 2019 Arctic summer sea ice minimum, using rates of loss from several recent years. While sea ice extent is now above extent for the same date in 2012, overall our projection for the minimum is lower than estimated in our previous post. Using the average decline rate of the past 12 years, from 2007 to 2018, the 2019 minimum is estimated to be 3.75 million square kilometers (1.45 million square miles). If the 2012 decline pattern is applied from August 14 forward, sea ice reaches 3.44 million square kilometers (1.33 million square miles). This is still above the 2012 summer minimum extent of 3.39 million square kilometers (1.31 million square miles). However, nearly all of the recent rates of sea ice loss lead to 2019 being second lowest in ice extent, surpassing 2007 and 2016.

 

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25 minutes ago, bluewave said:

Loss rate has slowed enough last few days for NSIDC extent to fall behind 2012 by 242k as of 8-15.

.............2012......2019

 8-13.....4.889......4.966.....77k behind

8-14.....4.724......4.970.....246k behind

 8-15....4.679......4.921.....242k behind

 8-16....4.619

8-17.....4.545

8-18.....4.520

8-19.....4.405

 8-20.....4.313

NSIDC updated their projection for the September minimum. They are now calling for a 2nd place finish behind 2012.

https://nsidc.org/arcticseaicenews/2019/08/dead-heat/

The ASINA team conducted a revised analysis of the likely course of the 2019 Arctic summer sea ice minimum, using rates of loss from several recent years. While sea ice extent is now above extent for the same date in 2012, overall our projection for the minimum is lower than estimated in our previous post. Using the average decline rate of the past 12 years, from 2007 to 2018, the 2019 minimum is estimated to be 3.75 million square kilometers (1.45 million square miles). If the 2012 decline pattern is applied from August 14 forward, sea ice reaches 3.44 million square kilometers (1.33 million square miles). This is still above the 2012 summer minimum extent of 3.39 million square kilometers (1.31 million square miles). However, nearly all of the recent rates of sea ice loss lead to 2019 being second lowest in ice extent, surpassing 2007 and 2016.

 

Back in late July, both the average statistical decline (2010-18 period) and sensitivity analysis indicated that it was likely that Arctic sea ice extent would fall below 4.000 million square kilometers at its minimum for only the second time on record. Since then, things have remained on track for such an outcome.

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35 minutes ago, ORH_wxman said:

Area and extent loss have slowed to a crawl the last couple days. We're now behind 2012 by about 300k on extent and 200k on area. 

We keep saying this ...than it's not - where are y'all getting your data... I've been utilizing NOAA's IMS ...and admittedly, it has not updated since the 11th ...but there curve was substantially more loss than 2012 as of the 11th ... it'll be interesting to see if that tend trajectory could have down such a drastic 45 deg angular change so abruptly and gone back across the 2012 slope - which is what would need to have taken place according to their products in order for the current 2019 to be less disastrous -

Anyway, may be a moot point - the AO is trying to rise in the GEFs ensemble. I don't get to see the Euro EOFs but... should it rise, that may alleviate the ice loss rates - slow it down ...and in fact, if that's true they may be one in the same already... 

I want to stress though, that there's nothing gained in the longer run by 2019 failing to surpass 2012 - it means nothing.... The longer termed issue with the polar ice cap remains dire... I'm hoping there isn't some coveted like idea that we are coming out of the arctic crisis?   ... just sayn'

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On August 17, Arctic sea ice extent was 4.635 million square kilometers (JAXA). Arctic sea ice extent remains on track of the second lowest figure on record.

If Arctic sea ice extent declines at the 2010-18 mean rate, it would achieve a minimum figure of 3.695 million square kilometers. The median rate would produce a minimum extent of 3.672 square kilometers.

Implied probabilities based on sensitivity analysis:

4.000 million square kilometers or below: 84%
3.750 million square kilometers or below: 57%
3.500 million square kilometers or below: 26%

Highest 25th percentile: 3.905 million square kilometers
Lowest 25th percentile: 3.486 million square kilometers

In sum, Arctic sea ice extent will very likely fall below 4.0 million square kilometers for only the second time on record.

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2 hours ago, Typhoon Tip said:

We keep saying this ...than it's not - where are y'all getting your data... I've been utilizing NOAA's IMS ...and admittedly, it has not updated since the 11th ...but there curve was substantially more loss than 2012 as of the 11th ... it'll be interesting to see if that tend trajectory could have down such a drastic 45 deg angular change so abruptly and gone back across the 2012 slope - which is what would need to have taken place according to their products in order for the current 2019 to be less disastrous -

Anyway, may be a moot point - the AO is trying to rise in the GEFs ensemble. I don't get to see the Euro EOFs but... should it rise, that may alleviate the ice loss rates - slow it down ...and in fact, if that's true they may be one in the same already... 

I want to stress though, that there's nothing gained in the longer run by 2019 failing to surpass 2012 - it means nothing.... The longer termed issue with the polar ice cap remains dire... I'm hoping there isn't some coveted like idea that we are coming out of the arctic crisis?   ... just sayn'

Here's some sources....the record we discuss isn't supposed to be about what it means longer term. Most of us know the longer term trend is down. But records are interesting to all of us in the weather community. Why do we sit around and track the thermometer at 101F on a hot summer day when the record is 102F? Does it really feel much different from 99F? Of course not, we're just tracking whether the record gets broken or not. FWIW, we've discussed when we think the first total melt out (definition below 1 million sq km of extent) will be in here:

https://www.americanwx.com/bb/topic/40881-when-we-will-see-an-ice-free-arctic/

https://www.americanwx.com/bb/topic/46677-when-will-the-2012-arctic-ice-extent-minimum-record-be-broken/?page=3

 

It does not appear we will set a new record this year based on JAXA, ubremen, and NSIDC. We'll see about the IMS plot you reference but is suspect that will flatten out at some point. 

https://docs.google.com/viewer?a=v&pid=sites&srcid=ZGVmYXVsdGRvbWFpbnxhcmN0aXNjaGVwaW5ndWlufGd4OjU1OGIwZWI0NGI2ZDI5YTM

https://seaice.uni-bremen.de/sea-ice-concentration/

https://ads.nipr.ac.jp/vishop.ver1/vishop-extent.html

 

 

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 I don't know… It strikes me a bit like people just not wanting a record to be broken I'm sorry it does.

Otherwise the IMS plots I supplied would've been part of the discussion all along and looks a bias  when potentially valid data is elided. 

 Maybe it's not that way OK… 

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15 minutes ago, Typhoon Tip said:

 I don't know… It strikes me a bit like people just not wanting a record to be broken I'm sorry it does.

Otherwise the IMS plots I supplied would've been part of the discussion all along and looks a bias  when potentially valid data is elided. 

 Maybe it's not that way OK… 

Well, it sounds like a subjective analysis then by you on other people's posting behavior. Not sure I can really help other than the below explanation:

If you go back through the beginning of this thread and previous Arctic sea ice threads, you'll note that IMS hasn't been used. It's been consistently NSIDC and JAXA...sometimes U bremen and previously Cryosphere Today (now defunct..but they used NSIDC data). 

I don't know a ton about IMS but my little experience with it from sheer recollection back to the 2009-2013 days is that it seems to lag the other datasets significantly. It will "catch up" to them eventually if it looks like it is deviating on a trend line. That is my guess on what happens this year as well. We won't have to wait long to find out. 

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12 hours ago, ORH_wxman said:

Well, it sounds like a subjective analysis then by you on other people's posting behavior. Not sure I can really help other than the below explanation:

If you go back through the beginning of this thread and previous Arctic sea ice threads, you'll note that IMS hasn't been used. It's been consistently NSIDC and JAXA...sometimes U bremen and previously Cryosphere Today (now defunct..but they used NSIDC data). 

I don't know a ton about IMS but my little experience with it from sheer recollection back to the 2009-2013 days is that it seems to lag the other datasets significantly. It will "catch up" to them eventually if it looks like it is deviating on a trend line. That is my guess on what happens this year as well. We won't have to wait long to find out. 

ISM is lagging by date ... as of last check... They seem to update that about every 10 days...and it's for the previous week, too...so by the time it's published it's an addition three or so days beyond that week... Aug 11 ... That's what I've seen from them since July.  They'll probably release an analysis for the 18th in about two days...  oy - 

As far as the subject crap - nah dude.  More like concern... I don't really care if people want/need/do/or don't have biases... I just want to know that what I'm reading isn't that - which admittedly is probably not going to happen in a public social media source.  :) word.   Just so we're clear. In order to make that assessment... I may sound I like I care about specific posting behavior ... but that's not it.  

I'm not sure anything you have said should invalidate IMS inclusion - not that you mean to...  I think it is at least worth it to vet why their plots vary... interesting. I'm wondering if it's density related. 

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