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ORH_wxman

Arctic Sea Ice Extent, Area, and Volume

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I agree with the low chance of beating 2012 at this point. I wanted to see a pretty good sized lead heading into late July/early August. 

I might go higher than 3% on extent but not by a lot. Maybe 10-20%. 

For area I probably wouldn't go higher though as we slightly trail 2012 in area. 

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20 minutes ago, ORH_wxman said:

I agree with the low chance of beating 2012 at this point. I wanted to see a pretty good sized lead heading into late July/early August. 

I might go higher than 3% on extent but not by a lot. Maybe 10-20%. 

For area I probably wouldn't go higher though as we slightly trail 2012 in area. 

What would you say the odds are of beating 2007 or 2016?

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Just now, lookingnorth said:

What would you say the odds are of beating 2007 or 2016?

On extent or area? I think 2007 both extent and area are very good chances to be surpassed by 2019...2016 has a good chance on extent but not as good for area. Prob like a 50/50 chance or less to pass 2016 area. 

 

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I agree. 3% is too low. 10-20% sounds pretty reasonable to me as well.

 

 

 

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In searching for forecasts for the minimum Arctic Sea Ice extent, I came across one source: https://www.arcus.org/sipn/sea-ice-outlook/2019/july

The median figure from that source is 4.28 million square kilometers. The statistical mean that I posted was 3.89 million square kilometers. I will probably re-run the data when I get back from abroad around 8/20 or so. By then, it should be much clearer whether 2019 can make a run at the 2012 record.

As I suspect Arctic sea ice data is not normally distributed, like others above, I believe the probabilities for extremely low minimum values are higher than what is shown statistically. I also expect this year to finish with a minimum extent below 4.00 million square kilometers.

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Europe's recent heat wave is pinching off a warm secluded ridge node and is modeled to slide west toward Greenland. 

I'm wondering if that may bring warming conditions to the terrestrial interface/boundary layer

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11 hours ago, csnavywx said:

A purely statistical model would have basically "missed" 2012 at this point. Probably 2007 as well. I suspect the issue has to with the behavior of extent numbers when volume gets very low.

It may also struggle under extreme blocking and dipole regimes like we are seeing this year. Its biggest miss or underestimation of melt from a June forecast was in 2015. July 2015 experienced the strongest blocking and dipole pattern during the 2013 to 2018 era.

June 2015 CPOM forecast September average extent......5.10....Verification.......4.63

11 hours ago, donsutherland1 said:

I agree. That's part of the reason I provided a brief discussion of what could change things. I suspect that changes in ice minima may not be normally distributed.

This was the most impressive piece of information from the statistical model that CPOM uses for their forecasts. 

The simulated melt pond fraction in June 2019 has been higher then in any June before.

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7-27-19 has a narrow lead of 214k over 7-27-12 for NSIDC extent. 2019 needs to maintain an average daily drop rate of 106k next 13 days in order not to fall behind 2012. This first 9 days of August was when 2012 experienced the record breaking decline. There was a 3 day interval with over 500k of losses during the deep Arctic storm. So it may be tough to catch up with 2012 later in the season if 2019 falls much behind next few weeks. We’ll see how it goes.

7-27-19...6.463

7-27-12...6.677

8-9-12.....5.088

9-16-12...3.340....lowest daily September minimum on record

ADF3BBE0-1A7A-4B5C-A448-CD117C958A7A.thumb.png.0c3c19d02f01e7d45fdaf4c04fab702d.png

 

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While there's a lot of weak ice, there isn't quite as much as 2012, so I expect this year to fall slightly behind by the end of the first week of August. Maybe 200k or so. I actually think we could see record low volume, but come in second on extent and perhaps 2nd or 3rd on area.

The MYI in the central CAB will undoubtedly make it, but given how warm winters have been the past few years, I expect it to start looking more and more like it did in 2016 at the end of the season, looking a little thin and ragged.

Also, given how unusual this year's -AO pattern was (partially due to a dynamic final PV warming), I would expect a reversion to the mean next year. But this is the Arctic, and you never know....

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On July 30, Arctic sea ice extent was 5.998 million square kilometers (JAXA). That broke the daily minimum record of 6.132 million square kilometers, which was set in 2012. It is also the earliest figure under 6.000 million square kilometers. The previous earliest figure occurred on August 3, 2012 when Arctic sea ice extent was 5.911 million square kilometers.

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It seems there's an underpinning 'agenda' to keep this year elevated above 2012 ... I guess for the sake of records?  I'm curious because I'm not sure why we are so preoccupied by finite distinctions and what those mean to specific records, when the specter of what's happening over the last 20 years is far more telling.  I would certainly hope that no one is coveting or even abstractly taking comfort in a acre less melt if it comes to that... 

In any case, last week I mentioned that the heat wave in western Europe was modeled to plausibly affect Greenland and now ..headlines to that effect are indeed foisted.   Granted CNN, 

https://www.cnn.com/2019/07/31/europe/greenland-heatwave-climate-crisis-intl/index.html ,  

... tends to spin toward aggrandizing in any attempt toward ratings that turn the gears of their media-profit-machine ... we'll just have to see if corroboration surfaces ... I believe some acceleration is likely though.

The deep tropospheric heat anomaly effectively severed, formulated a high latitude blocking node ...and that feature has since been retrograding toward Greenland. Still carrying along with it actual warm thicknesses within the anomalously tall H500 isohypsotic surfaces - in other words...a balloon of warm rich ice-sheet melting air - I was wondering if this may enhance the seasonal melt rate.  Seems to be at least according to CNN's dystopian formula - 

The question is, if so ... does any of this also effect an acceleration of ice loss in the total arctic?    

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16 minutes ago, Typhoon Tip said:

It seems there's an underpinning 'agenda' to keep this year elevated above 2012 ... I guess for the sake of records?  I'm curious because I'm not sure why we are so preoccupied by finite distinctions and what those mean to specific records, when the specter of what's happening over the last 20 years is far more telling.  I would certainly hope that no one is coveting or even abstractly taking comfort in a acre less melt if it comes to that... 

In any case, last week I mentioned that the heat wave in western Europe was modeled to plausibly affect Greenland and now ..headlines to that effect are indeed foisted.   Granted CNN, 

https://www.cnn.com/2019/07/31/europe/greenland-heatwave-climate-crisis-intl/index.html ,  

... tends to spin toward aggrandizing in any attempt toward ratings that turn the gears of their media-profit-machine ... we'll just have to see if corroboration surfaces ... I believe some acceleration is likely though.

The deep tropospheric heat anomaly effectively severed, formulated a high latitude blocking node ...and that feature has since been retrograding toward Greenland. Still carrying along with it actual warm thicknesses within the anomalously tall H500 isohypsotic surfaces - in other words...a balloon of warm rich ice-sheet melting air - I was wondering if this may enhance the seasonal melt rate.  Seems to be at least according to CNN's dystopian formula - 

The question is, if so ... does any of this also effect an acceleration of ice loss in the total arctic?    

I'm definitely with you on truly wanting/wishing that the ice lose would reverse course; which it looks like it will not anytime soon.

But saying that, what do you think of the concept that as the Arctic warms, lower latitudes could cool (especially in winter).

https://news.nationalgeographic.com/2017/07/global-warming-arctic-colder-winters-climate-change-spd/

** I suppose this could also go along with the idea that the Gulf stream could slow or stop... 

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NSIDC extent is only 163k above 2012 as of 7-30. 

7-30-19...6.237

7-30-12....6400

2019 needs to increase the decline rate next 10 days in order not to fall below 2012 on August 9th. The average daily decline rate last 10 days was 81k. This year would need an average 115k daily to keep up with 2012 over the next 10 days.

8-9-12.....5.088

9-16-12...3.340....lowest daily September minimum on record

The area is tracking a bit behind 2012 as of 7-30.

EB215E4F-8A41-49C2-9494-8B5C86D59E3F.png.137e19702e400a6c6bdeb0ea8922e949.png

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Extent definitely has a better chance to beating 2012 than area. We're 170K behind in area now and 2012 doesn't slow down any time soon. We'll need some breathtaking losses to keep pace. 

If we have enough compression of the pack though, extent could still challenge even if area does not. 

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On 7/31/2019 at 8:45 AM, FallsLake said:

I'm definitely with you on truly wanting/wishing that the ice lose would reverse course; which it looks like it will not anytime soon.

But saying that, what do you think of the concept that as the Arctic warms, lower latitudes could cool (especially in winter).

https://news.nationalgeographic.com/2017/07/global-warming-arctic-colder-winters-climate-change-spd/

** I suppose this could also go along with the idea that the Gulf stream could slow or stop... 

Firstly, I'm not sure the social-media community in this particular web destination really IS of the 'wanting/wishing' ilk  :)  ... I'll just expand on that a little more... but it was really a 'just in caser'

Imho, should 2019 somehow by excruciating number crunching  ( less than obviously ) fall short of 2012 ... was it really worth all the effort and writing...and annotated graphs and monitoring and ..well, basically obsession?   

We are not "making sure that happens" - by plying that effort.  I can understand statistical accuracy but I wonder if the real motivation for doing so lurks behind that excuse, because the bigger, longer term consequence of what the world faces is so dire right now that to do so ...could not be any more futile. If it falls short, nothing's different. Why then?  The longer vision, we're still f*!&ed folks.  

As far as that article... There's a lot of complexity that is not really discussed in that... In a general scope and concept it's not "un-clad" exactly ...But, there are ... synergistic effects that are 'emergent properties' and aren't really predictable... More over, those can have secondary ...tertiary spontaneities too... 

The blocking idea can come from other sources: 

First,  ... extinguishing planetary wave/dispersion into higher altitudes.  Think of it as where warm advection plumes go to die.  The vagaries of R-wave undulations over time, can create episodes where/when warm fluxes cause/contribute to tropospheric blocking ..  These are ephemeral in nature... If they persist ( causally ) it's the underpinning pattern that's supporting it.. The NAO domain is a good teleconnector to exemplify this.. It can fluctuate at intraweekly time scales because of this sort of transient phenomenon...  And is why seasonal predictions for that teleconnector - heh... good luck.  

Second ... blocking anywhere from that can happen in any era. 

Third, ... it is not abundantly clear that GW would in fact promote more of that to happen, because ... it's all still based upon gradients.  Without gradients...no air movement exists at all. From that very fundamental requirement of physics, working together with gravity over a curved surface...  without the first initial requirement of changing PV=NRT from one point to another...not of this, in fact, this conversation, can happen.... Why is that important?  Beyond the obvious ... the arctic also is said to be differentiating warmer/faster than everywhere else... Is that true in the middle troposphere?  If so... than the gradient is not necessary increasing because of GW... but, I suspect it is anyway... The arctic is just trying to catch up ...and in the interim ...we are witnessing extraordinary jet speed anomalies and have been now over the recent decades. Flights between NY and London...also across the expanse of the Pacific have registered historically fast ground-based velocity speeds in that time. This is happening because the warmer equator/sub-tropical latitudes are storing more water vapor ( concomitant with the GW ...) and fiddling with the math ... that is keeping heights slightly elevated; pressing ( as it were) against seasonal nadirs in the winter. Even if they are warming...they are not warming fast enough to compensate for the ambient steepening of that gradient that exists between ~ 35N and the 60 N girdle around the hemisphere.  This creates the hurried velocity saturation being observed...  

Lastly ... folks are forgetting that we are still moving through the 11, 22 and 300 year temporal super-position of the Max(min) solar.  Those times have been correlated strongly with -AO tendencies... That makes it incredible difficult to untangle 'how much' of blocking is a result of warming arctic ( as it relates to GW ) - vs how much was destined to take place as this solar expectation has arrived and we transpire through... I suspect like everything...there's shared forcing there... 

** The gulf stream stuff and the AMOC - that's a whole 'nother ball of wax.  The warming in the previous ... probably going back to the early 1980s is when it really started... has been adding fresh water to the surface of the Atlantic...  That's been accelerating particularly in the latter half of that multi-decadal time span. At some critical threshold the specific gravity has changed too much...and the buoyancy gained in the aqueous saline waters (at a given temperature).. slows and/or can stops the sinking water process... No sink = no drawing surface water N = break down of the Gulf Stream.  This was theorized back then, too... We are ( more likely so ) now seeing this being measured in the environment...  

Altering the transport of warm surface waters to higher latitudes certainly would effect circulation tendencies through the various meteorological circuitry over time...and time being a variable in climate - there we go...  

It's a mind boggling array of countermanding forces and whatever is left after canceling out ...dictates the systemic character.    

 

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2 hours ago, Typhoon Tip said:

Firstly, I'm not sure the social-media community in this particular web destination really IS of the 'wanting/wishing' ilk  :)  ... I'll just expand on that a little more... but it was really a 'just in caser'

Imho, should 2019 somehow by excruciating number crunching  ( less than obviously ) fall short of 2012 ... was it really worth all the effort and writing...and annotated graphs and monitoring and ..well, basically obsession?   

We are not "making sure that happens" - by plying that effort.  I can understand statistical accuracy but I wonder if the real motivation for doing so lurks behind that excuse, because the bigger, longer term consequence of what the world faces is so dire right now that to do so ...could not be any more futile. If it falls short, nothing's different. Why then?  The longer vision, we're still f*!&ed folks.  

As far as that article... There's a lot of complexity that is not really discussed in that... In a general scope and concept it's not "un-clad" exactly ...But, there are ... synergistic effects that are 'emergent properties' and aren't really predictable... More over, those can have secondary ...tertiary spontaneities too... 

The blocking idea can come from other sources: 

First,  ... extinguishing planetary wave/dispersion into higher altitudes.  Think of it as where warm advection plumes go to die.  The vagaries of R-wave undulations over time, can create episodes where/when warm fluxes cause/contribute to tropospheric blocking ..  These are ephemeral in nature... If they persist ( causally ) it's the underpinning pattern that's supporting it.. The NAO domain is a good teleconnector to exemplify this.. It can fluctuate at intraweekly time scales because of this sort of transient phenomenon...  And is why seasonal predictions for that teleconnector - heh... good luck.  

Second ... blocking anywhere from that can happen in any era. 

Third, ... it is not abundantly clear that GW would in fact promote more of that to happen, because ... it's all still based upon gradients.  Without gradients...no air movement exists at all. From that very fundamental requirement of physics, working together with gravity over a curved surface...  without the first initial requirement of changing PV=NRT from one point to another...not of this, in fact, this conversation, can happen.... Why is that important?  Beyond the obvious ... the arctic also is said to be differentiating warmer/faster than everywhere else... Is that true in the middle troposphere?  If so... than the gradient is not necessary increasing because of GW... but, I suspect it is anyway... The arctic is just trying to catch up ...and in the interim ...we are witnessing extraordinary jet speed anomalies and have been now over the recent decades. Flights between NY and London...also across the expanse of the Pacific have registered historically fast ground-based velocity speeds in that time. This is happening because the warmer equator/sub-tropical latitudes are storing more water vapor ( concomitant with the GW ...) and fiddling with the math ... that is keeping heights slightly elevated; pressing ( as it were) against seasonal nadirs in the winter. Even if they are warming...they are not warming fast enough to compensate for the ambient steepening of that gradient that exists between ~ 35N and the 60 N girdle around the hemisphere.  This creates the hurried velocity saturation being observed...  

Lastly ... folks are forgetting that we are still moving through the 11, 22 and 300 year temporal super-position of the Max(min) solar.  Those times have been correlated strongly with -AO tendencies... That makes it incredible difficult to untangle 'how much' of blocking is a result of warming arctic ( as it relates to GW ) - vs how much was destined to take place as this solar expectation has arrived and we transpire through... I suspect like everything...there's shared forcing there... 

** The gulf stream stuff and the AMOC - that's a whole 'nother ball of wax.  The warming in the previous ... probably going back to the early 1980s is when it really started... has been adding fresh water to the surface of the Atlantic...  That's been accelerating particularly in the latter half of that multi-decadal time span. At some critical threshold the specific gravity has changed too much...and the buoyancy gained in the acquiesce saline waters (at a given temperature).. slows and/or can stops the sinking water process... No sink = no drawing surface water N = break down of the Gulf Stream.  This was theorized back then, too... We are ( more likely so ) now seeing this being measured in the environment...  

Altering the transport of warm surface waters to higher latitudes certainly would effect circulation tendencies through the various meteorological circuitry over time...and time being a variable in climate - there we go...  

It's a mind boggling array of countermanding forces and whatever is left after canceling out ...dictates the systemic character.    

 

Thanks for the great response!! I'm actually coping this post for future reference.

Your probably right about the underlying reason for the article. And we very well could be f*!&ed.

But (if we want to very selfish and shortsighted), if the arctic is going to hell we might as well score some good winter storms.  :)    

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At least for the time being, the harshest melting conditions are focused over Greenland. NSIDC had a very small drop yesterday of 44k down to 6.192. It maintains a narrow lead over 2012 of 176k which was at 6.368. August 1-11, 2012 experienced the record breaking decline down to 5.021. This year would require an average daily decline rate of 106k to keep pace by August 11th.

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12 minutes ago, bluewave said:

At least for the time being, the harshest melting conditions are focused over Greenland. NSIDC had a very small drop yesterday of 44k down to 6.192. It maintains a narrow lead over 2012 of 176k which was at 6.368. August 1-11, 2012 experienced the record breaking decline down to 5.021. This year would require an average daily decline rate of 106k to keep pace by August 11th.

2012 has expanded it's area lead to 210k....the best chance for 2019 is if the Laptev can retreat further than 2012. That's the weak spot when comparing year over year.

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Zack Labe is reporting that July set the new lowest NSIDC average extent for the month. The only months not to set a new record low since 2016 so far have been ASO. 9 new monthly records in 3 years shows how much the Arctic has warmed.

https://mobile.twitter.com/ZLabe/status/1156938182832693249

New Record* -- 2019 averaged the lowest #Arctic sea extent in the satellite-era for the month of July. It was 1,880,000 km² below the 1981-2010 average. Data from

 
 
Updated record low #Arctic sea ice extent months -

data (satellite-era from 1978/1979) --------------

2018 : January

2018 : February

2017 : March

2019 : April

2016 : May

2016 : June

2019 : July

2012 : August

2012 : September

2012 : October

2016 : November  

2016 : December

 
 
 
 

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I like the new NSIDC sea ice extent chart. You can add the ±2σ band to the display now.

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12 hours ago, bdgwx said:

I like the new NSIDC sea ice extent chart. You can add the ±2σ band to the display now.

But I don't like the new colors because I was so used to the old version.

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On 8/1/2019 at 9:25 AM, ORH_wxman said:

2012 has expanded it's area lead to 210k....the best chance for 2019 is if the Laptev can retreat further than 2012. That's the weak spot when comparing year over year.

The good news is that the ice hasn't been able to beat the last record low from 7 years ago. 

Which could mean an ice free summer Arctic probably won't happen until the end of the 21st century.

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Large -299k drop in NSIDC extent over the last 2 days. This puts 2019 +259 k ahead of 2012 as of August 2nd. 2019 needs to maintain an average daily decline rate of 97k over the next 9 days to hold even with 2012 by the 11th. 

NSIDC extent

8-2-19.....5.893

8-2-12.....6.152

8-11-12....5.021

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May through July set new Arctic records for warmth, surface pressure, and 500 mb heights.

 

FE29465C-4B5B-446A-895A-CD5DDAE10CA6.png.5d5e338e3f822e02ece04ee67f61f326.png

 

344C4EC8-A417-49B7-9475-37FF94BA5E35.png.4454979703ef2cfb913a2daaac96eef6.png

965E1311-2D24-415C-9088-0D1561DB6B78.png.b26b4838f9fd3c4a44ea96e79b1bc616.png

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2 hours ago, bluewave said:

May through July set new Arctic records for warmth, surface pressure, and 500 mb heights.

 

FE29465C-4B5B-446A-895A-CD5DDAE10CA6.png.5d5e338e3f822e02ece04ee67f61f326.png

 

344C4EC8-A417-49B7-9475-37FF94BA5E35.png.4454979703ef2cfb913a2daaac96eef6.png

965E1311-2D24-415C-9088-0D1561DB6B78.png.b26b4838f9fd3c4a44ea96e79b1bc616.png

Source?

 

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We are entering the big decline week when 2012 pulled ahead of all other years. This was during the period of the Great Arctic Cyclone. 

NSIDC extent

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

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

8-5......5.768

8-6......5.632

8-7......5.467

8-8......5.256

8-9......5.088

8-10....5.118

8-11....5.021

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i think many folk give GAC12 too much credit for the losses over Aug that year ( sure it had impact) but the ice was already pretty messed before it struck?

Todays ice is pretty messed up so let's see what happens eh?

 

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