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Arctic Sea Ice Extent, Area, and Volume


ORH_wxman
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There's a decent amount of really low concentration ice in the Hudson and Kara right now so I expect extent loss numbers to still remain strong over the next week, but the area numbers should stall pretty good with the big reverse dipole. I'd expect then we eventually see an extent stall once Kara/Hudson melt out.

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On 7/16/2018 at 9:51 AM, ORH_wxman said:

There's a decent amount of really low concentration ice in the Hudson and Kara right now so I expect extent loss numbers to still remain strong over the next week, but the area numbers should stall pretty good with the big reverse dipole. I'd expect then we eventually see an extent stall once Kara/Hudson melt out.

Can you post the area numbers again, Will? Are we still close to 2009/2013/2014?

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1 hour ago, nzucker said:

Can you post the area numbers again, Will? Are we still close to 2009/2013/2014?

No, 2009, 2013, and 2014 have fallen behind the melt pace of 2018...we're pretty close to 2017 right now actually. I am expecting though that we will stall pretty good since we've now almost melted out the Kara/Hudson and the pattern in the CAB is pretty good for the ice for the foreseeable future. We're way behind years like 2007 and 2012 or 2016 so there's basically zero chance to have something like a top 3 finish. I don't have the exact numbers in front of me at the moment, but I'll post them as soon as I have a chance.

Based on where things stand right now, I'm expecting a result a little lower than a 2013/2014 but higher than last year. We'll see if that changes.

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58 minutes ago, ORH_wxman said:

No, 2009, 2013, and 2014 have fallen behind the melt pace of 2018...we're pretty close to 2017 right now actually. I am expecting though that we will stall pretty good since we've now almost melted out the Kara/Hudson and the pattern in the CAB is pretty good for the ice for the foreseeable future. We're way behind years like 2007 and 2012 or 2016 so there's basically zero chance to have something like a top 3 finish. I don't have the exact numbers in front of me at the moment, but I'll post them as soon as I have a chance.

Based on where things stand right now, I'm expecting a result a little lower than a 2013/2014 but higher than last year. We'll see if that changes.

Looks above most recent years on Bremen extent:

arcticextent.thumb.png.e2c6e1c7c49dc96c9a06c821b2722a29.png

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I feel it was probably already mentioned but what may be the reasoning of the prolonged low pressure over the CAB and into Canada/Greenland area? I think I had seen the idea of the late SSW being a possible reason. It is interesting to see of course and does this mean that this upcoming winter season may feature something different than we have seen in recent years?

Not necessarily recovery by any means but less harsh conditions then we have seen. Also with the possibility of AMO flipping or showing signs it may what impact will this have in ice conditions particularly on the Atlantic side.

Thanks for any comments trying to get better at understanding what is occurring up in Arctic

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12 minutes ago, so_whats_happening said:

I feel it was probably already mentioned but what may be the reasoning of the prolonged low pressure over the CAB and into Canada/Greenland area? I think I had seen the idea of the late SSW being a possible reason. It is interesting to see of course and does this mean that this upcoming winter season may feature something different than we have seen in recent years?

Not necessarily recovery by any means but less harsh conditions then we have seen. Also with the possibility of AMO flipping or showing signs it may what impact will this have in ice conditions particularly on the Atlantic side.

Thanks for any comments trying to get better at understanding what is occurring up in Arctic

I'm not sure if there's any connection to the persistent low pressure up in the arctic the last month or so and the SSW late in the cold season.

 

If the AMO actually does plunge into negative territory on a multi-year scale, then we'd probably see less warm intrusion from the Atlantic. The negative phase of AMO has previously been linked to colder arctic temperatures, but it remains to be seen how much this would actually offset the underlying warming trend. There was some literature not too far back that had shown the recent arctic warming was amplified by 30-50% since the early 1990s due to the AMO shift. But with the loss of a lot of multi-year ice and the underlying warming trend, it's hard to say just how much affect a negative AMO would have.

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1 minute ago, ORH_wxman said:

I'm not sure if there's any connection to the persistent low pressure up in the arctic the last month or so and the SSW late in the cold season.

 

If the AMO actually does plunge into negative territory on a multi-year scale, then we'd probably see less warm intrusion from the Atlantic. The negative phase of AMO has previously been linked to colder arctic temperatures, but it remains to be seen how much this would actually offset the underlying warming trend. There was some literature not too far back that had shown the recent arctic warming was amplified by 30-50% since the early 1990s due to the AMO shift. But with the loss of a lot of multi-year ice and the underlying warming trend, it's hard to say just how much affect a negative AMO would have.

No worries always wonders we arent fully sure of yet in this changing climate. Cool stuff to try and get an idea for in the future with such fairly drastic patterns changing and locking in for time periods up there. And thanks for the info on AMO ill have to go back and check things out then but that is a concern even with the change that things might have already changed enough to counteract that -AMO phase. 

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On 7/16/2018 at 9:51 AM, ORH_wxman said:

There's a decent amount of really low concentration ice in the Hudson and Kara right now so I expect extent loss numbers to still remain strong over the next week, but the area numbers should stall pretty good with the big reverse dipole. I'd expect then we eventually see an extent stall once Kara/Hudson melt out.

NSIDC area has indeed stalled the last couple days...we'll see how long that goes. But we're back to being basically a dead heat with 2013/2014.

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17 hours ago, ORH_wxman said:

I'm not sure if there's any connection to the persistent low pressure up in the arctic the last month or so and the SSW late in the cold season.

 

If the AMO actually does plunge into negative territory on a multi-year scale, then we'd probably see less warm intrusion from the Atlantic. The negative phase of AMO has previously been linked to colder arctic temperatures, but it remains to be seen how much this would actually offset the underlying warming trend. There was some literature not too far back that had shown the recent arctic warming was amplified by 30-50% since the early 1990s due to the AMO shift. But with the loss of a lot of multi-year ice and the underlying warming trend, it's hard to say just how much affect a negative AMO would have.

Me neither ... considering that SSW events time-lag correlate to a reduction of the +AO phase state, which is opposite of what is occurring with a strong(ening)(ened) we see now...  

The other aspect, ... the termination of down-welling warm plumes that are theorized to cause increased static stability in the upper troposphere over the arctic --> breakdown of storm strength and collapse of the vortex (whereby/when blocking episodes ensue)... all that: the end phases of those events are either a logarithmic decay, or a strong analog for a that behavior, as they disappear in a very gradual extinction... 

Compounding that fade out ... it is unclear as we then relay winter hemispheres, if they effect summer circulation across the virtual boundary of seasonality.   Summers typically feature no thermal flux of any kind between approximately April/May thru late October or so... Contrasting to the starkly increased tumult of thermal cool and warm events that pop off and decay at different time expanses and magnitudes during winter.  So if any preceding mechanism is in place, not sure I see how sufficient that forcing would remain when there is virtually no signature/marker left in the data that suggests anything at all still exists..   

Seems unlikely...  but hell... maybe the system goes by a kind of first law of Newtonian dynamics ...where it's going to keep behaving per it's last forcing until acted upon by another force sufficiently strong enough to effect a new course...  So as the a-hole careens through the intersection and causes a pile-up...he/she keeps on rollin blithely away and is no where to be seen as the carnage lingers on - heh.  I like that 

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5 minutes ago, bluewave said:

Perhaps .. I'm not sure I agree with the tone of the mathematician cited often throughout that University of Washington source, either - 

case in point: " "The good news is the indicators show that this slowdown of the Atlantic overturning circulation is ending, and so we shouldn't be alarmed that this current will collapse any time soon," 
 

Oh really - that seems a little preclusive if not a presumptuous leap based upon the reasoning supplied in the article, and only 14 years worth of empirical data...  

It is what it is... he she could be right.  

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Paltry area losses continue...now we trail only 2009 in the post-2007 years. But we're still really close to 2013/2014. The ensembles are trying to show a change in the pattern finally as we head into August....we'll see if that happens. We've had some years where an august pattern change mattered a lot....2014 was one of them. That year was destined to be the least ice melt since 2006 before a big shift to a dipole pattern for a couple weeks in August really hammered the ESS arm of ice....and it finished just under 2013 instead. Still a lowish melt year in the post-2007 context, but it could have been even less.

The ice this year is thinner than 2014, so a pattern change could matter more this season. As usual though, I'd like to see this get solidly inside of 7 days before really buying a big shift. We've seen some of these shifts in recent years get muted or they are just very transient and it flips back to the negative dipole quickly.

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On 6/28/2018 at 5:56 PM, raindancewx said:

The AMO & 8/1 ice extent, for 1979-2017 when compared to 1979-2016, saw an increased r-value relationship. Jan-May AMO value is down 0.16 from last year (+0.08 v. +0.24). Theoretically worth around 0.5 million sq km in sea ice extent.

NdNUQBI.png

 

As of July 21, ice extent is +0.5 million square km above last year. Math for the win.

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Another measure of how strong the reverse dipole is this summer.

Yesterday's high of 5.2°C in #Iqaluit, Nunavut is coldest on record for July 17. Previous was 5.4°C in 1978. Records kept since 1946. #NUwx #Nunavut #North
 
Alert, Nunavut hit 10°C for the first time of the year yesterday, 2 weeks later than normal (1981-2010). #Arctic #North #Nunavut
 
Yesterday's high of 0.9°C in Resolute, Nunavut is coldest on record for July 21, beating 1.1°C in 1954. Records kept since 1948. #Nunavut #NUwx #Arctic
 
 
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I wouldn't take the thickness map from dmi seriously...that area melts out almost every year. You could probably thicken it with some compression if everything was perfect but I'm quite skeptical it's real in an area that big. 

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This melt season has been another clunker. 

 

But this is absurd.

 

Modis also confirms this.  The only explanation is the lack of regrowth the past two winters.

 

There is almost no way any of that ice outside the darker purple areas is going to survive. 

 

And some of the purple regions will recede. 

I don't know what it will end like. 

 

On nevens forum most of us have been very vocal about this season being a top 10-7 finish. 

 

Well the past week a gigantic area that has received mostly cloudy or foggy conditions all summer has abruptly collapsed. 

Cryosat at the end of April showed this region being incredibly thin.

 

The thicker ESS and Laptev regions have gotten hit hard. 

 

This is really amazing. 

Area and extent.

Especially extent is about to plummet. 

Probably going to be in the 2015-2017 area at the end. 

A paradigm shift outside the melt season is clearly at hand. 

 

 

 

Arctic_AMSR2_nic (1).png

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Wow. A friv post...must mean something exciting is happening in melt season. 

 

All joking aside, I still appreciate the friv analysis...he even gets sh*t at neven's forum for not being alarmist enough. 

 

But i I agree with friv here...this is pretty impressive in the ESS. It's going to melt down far...more than what we thought possible even a few days ago. This is probably a combo of weak ice growth there and some intense warmth that happened early in July which wiped out the snow cover on the ice. The snow cover on the ice is an underrated aspect...esp in FYI. 

 

We may challenge a top 5 here...I think top 3 is still out of reach but a top 5 is possible. Esp in area. I think a top 3 in extent will be hard. 2015 compacted a lot and we would need to see big compaction again. Esp since the CAA is still pretty icy compared to the low years. 

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58 minutes ago, ORH_wxman said:

Wow. A friv post...must mean something exciting is happening in melt season. 

 

All joking aside, I still appreciate the friv analysis...he even gets sh*t at neven's forum for not being alarmist enough. 

 

But i I agree with friv here...this is pretty impressive in the ESS. It's going to melt down far...more than what we thought possible even a few days ago. This is probably a combo of weak ice growth there and some intense warmth that happened early in July which wiped out the snow cover on the ice. The snow cover on the ice is an underrated aspect...esp in FYI. 

 

We may challenge a top 5 here...I think top 3 is still out of reach but a top 5 is possible. Esp in area. I think a top 3 in extent will be hard. 2015 compacted a lot and we would need to see big compaction again. Esp since the CAA is still pretty icy compared to the low years. 

Are we sure that isn't satellite error? It seems like an awfully big change from just a week or so ago, not sure if that's possible.

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Don't normally post here because much of the discussion is out of my knowledge level. But I do know that each week we pass (with cold, cool, average, or even not blazing temps) towards early September minimum is crucial. So just looking at the 6z GFS, it doesn't look that bad for surface temps. 850 temps do show pushes of much above normal temps but surface temps are at or just above freezing (more reasonable). So I think the big question is cloud cover; but again the farther into August we can get the lower the sun angel and the less affect of clear skies.

https://www.tropicaltidbits.com/analysis/models/?model=gfs&region=nhem&pkg=T2m&runtime=2018072906&fh=0

 

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3 hours ago, FallsLake said:

Don't normally post here because much of the discussion is out of my knowledge level. But I do know that each week we pass (with cold, cool, average, or even not blazing temps) towards early September minimum is crucial. So just looking at the 6z GFS, it doesn't look that bad for surface temps. 850 temps do show pushes of much above normal temps but surface temps are at or just above freezing (more reasonable). So I think the big question is cloud cover; but again the farther into August we can get the lower the sun angel and the less affect of clear skies.

https://www.tropicaltidbits.com/analysis/models/?model=gfs&region=nhem&pkg=T2m&runtime=2018072906&fh=0

 

Don't be fooled by surface temps. They never deviate much from about 1C at this time of year. This is due to heat exchange between the ice and the overlying atmosphere. 850/925 temps and winds are important. Even if 850s were at 20C with the sun out at full blast, surface temps would not rise much due to heat absorption from the ice phase-changing to water.

It's the same principle as having ice in your drink. The temperature of the drink will not rise much until it is nearly all melted.

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On 7/28/2018 at 12:59 AM, nzucker said:

Are we sure that isn't satellite error? It seems like an awfully big change from just a week or so ago, not sure if that's possible.

Worldview seems to corroborate the satellite data. Lots of soupy/ragged looking ice over there. Typically symptomatic of a reduction of floe size as it thins.

It looked relatively fine up until the 15th or so, but deteriorated quickly after that.

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The forecast is favorable for ice loss on Pacific side the first part of the week. 

Before a massive negative dipole takes over. 

However unlike the traditional ice preserving reverse dipoles.

 

This one is completely high pressure dominated.  With the vortex over the CAA. 

The Atlantic front gets hit hard but THE area that will suffer the most is the Laptev region.

 

With a very warm WWA fetch and a lot of sun right as the insolation drops below 400wm2 around the 5th.

Its really a perfect situation to really smash the atlantic front and laptev from well inside the 80N mark.

 

The ESS gets pretty solid sun and WAA.

 

However mixing would be required more there since the surface fetch is over so much ice as well.

 

The beaufort has a very defined area between ice that's toast and safe. 

Looks a lot more fun than a week ago.

 

And yeah nzucker GIS has been very cool and snowy this summer.

Almost zero days with any substantial ridge. 

 

 

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