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Arctic Sea Ice Extent, Area, and Volume


ORH_wxman
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7 hours ago, nzucker said:

It looks blocked by medium concentration ice in the image above. Is that refreezing in the Canadian Arctic Archipelago by 9/9?

He's prob talking about the southern route. The deeper main channel northern route never opened this year. 

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20 minutes ago, stadiumwave said:

In his defense...that is not how the media reported it. Big headlines & the words unprecedented used. I looked at the satellite data & thought "What the heck?", it's not open. 

The southern route opens all the time...it's even opened in some years pre-2000...I guess the fact that some icebreaker decided to do it earlier than other crossings made it some big deal. The CAA this year definitely didn't melt back as much as a lot of recent years.

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On 9/22/2017 at 5:59 AM, csnavywx said:

As we move into the re-freeze, the summer pattern is fading and is being replaced by a now-familiar sight: strong to extreme blocking near the Kara/Barents and Scandinavia.

ecmwf-ens_z500a_nhem_8.png

 

ecmwf-ens_T850a_nhem_8.png

Yeah, what the hell is going on? We're having a more summerlike pattern now in mid-late September than we did in mid-late August, and temperatures are almost as warm for it. I've never seen such a large area of anomalously high heights across the midlatitudes and polar regions. It looks like the 2015-2017 pattern is continuing, and at this rate, we might get another warmest year out of 2017, which I was not expecting a few months ago.

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VEI 5/6 eruptions in that portion of the globe are particularly effective in lowering global temperature. The effect would be on the order of 0.2-0.3C, provided the same eruption size. A weaker eruption might be closer to 0.1C, and a VEI6 may get closer to 0.4C. Peak cooling is generally 12-20 months after an eruption of that magnitude, though the tail can last up to 4-5 years. There is typically a rebound effect above the baseline a few years after a major eruption as masked radiative forcing emerges over a cooled surface.

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2 hours ago, csnavywx said:

VEI 5/6 eruptions in that portion of the globe are particularly effective in lowering global temperature. The effect would be on the order of 0.2-0.3C, provided the same eruption size. A weaker eruption might be closer to 0.1C, and a VEI6 may get closer to 0.4C. Peak cooling is generally 12-20 months after an eruption of that magnitude, though the tail can last up to 4-5 years. There is typically a rebound effect above the baseline a few years after a major eruption as masked radiative forcing emerges over a cooled surface.

we need a vei 7 eruption to really cool down global temps..

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  • 2 weeks later...
2 hours ago, BillT said:

the wishcasting about the sea ice was hilarious, so many saying lowest ice ever this year were so wrong and silent for weeks now.......

Well it did hit lowest extent maximum in the middle of winter, from recorded data, so that is enough in itself let alone the still distinct lowering of ice volume is still quite noticeable. Recently it has been about on par with refreeze nothing too crazy from what I have seen thus far so, rather uneventful but hey thats a good thing so far we will see how it plays out in about a month cause things started weird in mid november.

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5 hours ago, so_whats_happening said:

Well it did hit lowest extent maximum in the middle of winter, from recorded data, so that is enough in itself let alone the still distinct lowering of ice volume is still quite noticeable. Recently it has been about on par with refreeze nothing too crazy from what I have seen thus far so, rather uneventful but hey thats a good thing so far we will see how it plays out in about a month cause things started weird in mid november.

Arctic ocean temps remain fairly well above normal, though not quite as bad as last year. I suspect we'll see a slowdown in the refreeze. Not calling for catastrophe, but certainly unlikely to be a big rebound.

meanT_2017.png.110eedf41dc14574b23b44144716402c.png

vs

meanT_2016.png.3e80d37a6e2f60f033cdaff1398c0467.png

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1 hour ago, WidreMann said:

 

Arctic ocean temps remain fairly well above normal, though not quite as bad as last year. I suspect we'll see a slowdown in the refreeze. Not calling for catastrophe, but certainly unlikely to be a big rebound.

meanT_2017.png.110eedf41dc14574b23b44144716402c.png

vs

meanT_2016.png.3e80d37a6e2f60f033cdaff1398c0467.png

Do these air temperature changes have any substantial effect on the ice melting process?

My impression was that melting is mostly driven by direct solar heating and increased sea water temperature.

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24 minutes ago, etudiant said:

Do these air temperature changes have any substantial effect on the ice melting process?

My impression was that melting is mostly driven by direct solar heating and increased sea water temperature.

In this case, the concern is ice freezing and snowpack. The warmer temps could also be correlated with warmer SSTs, though which drives which (if not both) is a question I am not qualified to answer. In any case, we did see last year how extreme warmth slowed down and at times reversed the sea ice extent trajectory, so I am hesitant to say that the temperatures don't matter.

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The biggest thing the ice has going for it in the winter is that the AMO anomaly tends to end up at about 60% of its Summer values in Winter - which would be a much colder Atlantic than last winter. Last Summer was like +0.45 and went to +0.279 for Nov-Apr. This year, more like +0.325 in July-Sept, been assuming +0.15 or so for Nov-Apr, which is much less rare in terms of warmth.

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Winter temperatures DO matter -- to an extent. My personal favorite is freezing degree days, but you could use other measures just as well. I use FDDs because of the easy relationship to ice thickening. Ice grows quickly at first, but growth slows as it insulates the underlying water from the atmosphere and slows heat exchange. This principle works in reverse: a degree or two of warming doesn't matter all that much at first because the loss in spring thickness is initially small. However, further warming causes increasingly larger spring thickness losses as the relationship of FDD anomalies to ice thickness is exponential. When you start dropping below 2500-3000 FDDs, the spring thickness loss rapidly drives upward. The critical point (based on PIOMAS thickness experiments) seems to be around 1.6m. Below that thickness, ice doesn't survive the summer in the basin, almost no matter how favorable the weather is.

Add 2C to last winter's ridiculously warm winter and place a 2007 or 2012 style summer on top of that and you've pretty much got a blue Arctic Ocean at the end of the summer. That kind of scenario is probably 15 years away still.

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  • 1 month later...
  • 4 weeks later...

Rumor has it that U.S. / Russia are playing HAARP games with each other.  (Yup, Russia has their own version as well). 

Notice how the last couple years, Siberia has had enormous, record cold near the beginning of both winters.  Now their gettin back at us.   

These patterns are laughably fixed, wake up if u can’t see it.

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On 12/1/2017 at 9:59 PM, lookingnorth said:

The Bering and Chukchi Seas apparently have unprecedented levels of open water for this time of year.

https://insideclimatenews.org/news/30112017/arctic-sea-ice-extent-record-chukchi-bering-sea-alaska-ocean?

Probably not a coincidence that there has been so much -EPO since 2013. 
The NAO has been positive something like 5 years in a row, but if you map 500mb heights, there is a spike positive anomaly over Greenland. 

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1 hour ago, Vice-Regent said:

No games here, it's called all or nothing amplification of the flow with the PV getting stuck over North America. Blocking is the hallmark of stagnant weather patterns.

 

Yeah but this type of blocking is a bit over the top..extremely stagnant.  

Creating or intensifying High pressure blocking is easily done with the right tools mentioned above. 

Look at temps for next 5 days...North Pole temporarily relocated to central Canada. 

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3 hours ago, Sophisticated Skeptic said:

 

Yeah but this type of blocking is a bit over the top..extremely stagnant.  

Creating or intensifying High pressure blocking is easily done with the right tools mentioned above. 

Look at temps for next 5 days...North Pole temporarily relocated to central Canada. 

It's a complex story. No doubt about it. One could be fooled into a false sense of security, uncanny.

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Don't have to guess around about Arctic sea ice thickness anymore these days. Cryosat is pretty damn reliable as far as freeboard goes. This year doesn't look so bad in the central Arctic. Linky: http://cryosat.mssl.ucl.ac.uk/qa/freeboard.php

5a45f85d2c642_getimage2(1).png.0238a6fcbb17fec87c452470d66a8dc7.png

2017 November 10th to Dec 9th

getimage2.png.d6c29f504708ac67f7f03b978200063a.png

2016 15th Nov to 14th Dec

5a45f85a4a3a1_getimage2(2).png.7c5c667f2ec06f6360993bbc6e0b4acc.png

2012 6th November to 5th December

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