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Arctic Sea Ice Extent, Area, and Volume


ORH_wxman
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Jaxa had a gain of 38k yesterday....so it's possible we have hit the extent minimum. If we have, then the jaxa min was 4.54 million sq km. This would rank 8th lowest above 2017, 2016, 2015, 2012, 2011, 2008, and 2007.

 

Area loss is still crawling along (around 5k loss today)....area is currently at 3.2 million sq km. It is probably very close to the minimum but I will wait until it is reached to reconcile my predictions from the end of June data. If area loss doesn't change much more, then this would rank 9th lowest (same list as above, but area is higher than 2010 unlike extent).

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On ‎7‎/‎2‎/‎2018 at 9:07 AM, ORH_wxman said:

My prediction for final sea ice area minimum is 3.30 million sq km +/- 200k.

Below is a histogram of results taking each year's melt from here on out and subtracting that amount from 2018's area on June 30th....as you can see, the highest melt from June 30th onward was in 2016 (which produces the lowest potential result). If we matched that, we would see an area minimum of 2.91 million sq km. That would be 5th lowest on record. Every other result gives us an area over 3.0 million sq km. I had previously taken the 1979-2010 average because area loss from June 30th onward had seen no trend...but recent years like 2016 and even 2017 (which had large area loss after June 30th) have put the trend line slightly negative...so I've started using the post-2007 area loss average to augment the prediction....hence the 3.30 million sq km prediction. The average of all years would produce a minimum of 3.59 million sq km...instead of just the post-2007 average of 3.30 million sq km.

July2018_SIA.png.4f968af79f7445ef6500c9e9dd1257b6.png

 

 

 

As for extent? Extent is much harder to predict....compaction can play a large role as we saw in 2015 when the area min was 3.1 million sq km but the extent min was down near 4.25 million sq km. The NSIDC September average is probably easier to predict. For the daily min extent on NSIDC, I'll predict a 4.75 million +/- 300k and for a monthly average, I'll predict 4.9 million +/- 300k.

 

Knock about 200k off the daily number for the jaxa daily minimum extent since jaxa changed their algorithm back in 2014.

 

 

 

Time to bump this as it looks like the NSIDC area minimum has been reached.

 

The min area likely occurred 2 days ago at 3.17 million sq km. This ranks 9th lowest. My prediction above was for 3.3 million sq km +/- 200k...so this falls within that range. Taking the post-2007 average of area losses continues to be a better predictor than all previous years. The 3.17 million result was the 38th percentile of all the potential outcomes using only post-2007 area loss. This was around one half of a standard deviation, so not a strange result.

 

The other typically less accurate prediction is extent. My NSIDC daily extent minimum prediction was 4.75 million sq km +/- 300k  (and Jaxa would have been around 4.55 million sqkm). I'm not completely sure if the NSIDC extent min has occurred yet, but if it hasn't, the difference should be trivial from here on out. 2 days ago, the NSIDC extent bottomed out (for the time being at least) at 4.55 million sq km. It is still only 4.56 million sq km, so it's possible it falls back below 4.55 million sq km...though it is unlikely it will fall much below that if it does. The extent prediction was actually good this time as it falls within the margin set. In a strange nuance this year, jaxa extent is pretty close to NSIDC...usually it is close to 200k lower, but not this year. Jaxa min so far is 4.51 million sq km, so only 40k below NSIDC so far. So as a result, my jaxa prediction is really close to perfect. Again, these both could fall slightly more, but it's doubtful it would be more than trivial amounts. The current extent min on jaxa ranks 8th lowest, and the min on NSIDC ranks 6th lowest. 2017 and 2008 were both a little bit higher than 2018 on NSIDC extent.

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On July 31, 2018 at 1:24 PM, ORH_wxman said:

The winter of 2007-2008 was a big deal too...not just the 2007 melt season. At the end of 2007, the arctic still had a lot of MYI leftover, but a huge portion of it got exported in the winter. If it had been recycled back into the Beaufort gyre, then it's possible we would have reverted a little more to years like 2005. Still low, but not wiping out the pacific side almost every year. It would have eventually been wiped out with some of those years like 2011 and 2012, but who knows how the progression would have looked with more MYI...the temp profiles may have been different. Hard to say for sure. The first year ice doesn't get thick enough now in the Chukchi to protect the beaufort gyre from warmer waters. We started to see a recovery in the gyre with the very cold 2013 and 2014 seasons combined with decent winter patterns of lower export, but then 2015 had an epic July dipole that wiped out the MYI over there. I think the only way we'd get back to anything that looks like a pre-2007 year would be to have an anomalously cold winter up there combined with a cold melt season....but that type of sustained cold is nearly impossible to come by in the arctic...we only seem to be able to get it maybe 1-2 months at a time.

Of course, a big volcanic eruption may do the trick too...the arctic tends to cool more rapidly than anywhere else from aerosols.

Is this why you were suggestion that some residual impact from Pinatubo may have contributed to the abysmal arctic regime of the 1994-1995 winter?

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Getting very close to the NSIDC annual minimum extent. Most recent update was at 4.601 million sq km. A minimum in the 4 to 5 million sq km range has been typical for the new post 2007 Arctic. 

4 to 5 million sq km minimums 

2018

2017

2016

2015

2011

2010

2008

2007

Below 4 million sq km

2012

Slightly above 5 million sq km

2014

2013

2009

 

 

 

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Bluewave, I think you are referencing the 5 day average....the daily on NSIDC did get as low as 4.55 million sq km.

I'm actually not 100% sure what NSIDC uses...I think they might actually use the 5 day average as the min if I recall correctly, so your number might be more "official".

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4 hours ago, ORH_wxman said:

Bluewave, I think you are referencing the 5 day average....the daily on NSIDC did get as low as 4.55 million sq km.

I'm actually not 100% sure what NSIDC uses...I think they might actually use the 5 day average as the min if I recall correctly, so your number might be more "official".

They will probably issue the official annual minimum extent in the next few days. I used the latest daily reading from the chart below.

 

IMG_0244.thumb.PNG.4658a70750d2d03d01f8c568156f7c00.PNG

 

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3 hours ago, bluewave said:

They will probably issue the official annual minimum extent in the next few days. I used the latest daily reading from the chart below.

 

IMG_0244.thumb.PNG.4658a70750d2d03d01f8c568156f7c00.PNG

 

Yeah the interactive graph uses the 5 day mean....it's updated daily, so its a daily reading, but the data is a 5 day average. The single day reading is actually 4.56 million sq km today. Like I said before, I can't remember if they use that or the 1 day reading as the min...but looking back at past mins, I think they use the 5-day reading that's on the graph. I seem to remember them explaining that the single day jumps can be a bit volatile and produce faux numbers on the margins, so they prefer to smooth it out. JAXA actually does this too but they do it over a 2 day average. We'll know soon enough. Not that there is a big difference...

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8 hours ago, ORH_wxman said:

Yeah the interactive graph uses the 5 day mean....it's updated daily, so its a daily reading, but the data is a 5 day average. The single day reading is actually 4.56 million sq km today. Like I said before, I can't remember if they use that or the 1 day reading as the min...but looking back at past mins, I think they use the 5-day reading that's on the graph. I seem to remember them explaining that the single day jumps can be a bit volatile and produce faux numbers on the margins, so they prefer to smooth it out. JAXA actually does this too but they do it over a 2 day average. We'll know soon enough. Not that there is a big difference...

This would probably have been a minimum closer to 7 million sq km in a pre 2007 Arctic world. Zack Labe posted a great chart on how low the pressures were over the Arctic the last two summers. Lowest pressures since the 1990's. But extents well below those levels.

Another summer of predominately cyclonic (low pressure) conditions over the#Arctic polar cap (>65°N) --> cloudy and "cool" pic.twitter.com/7LySJd5pqN
 
DnbYcmtU0AItYY7.jpg-small.jpg.757efda5e690bf8e7eaaff1527fcda72.jpg
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1 hour ago, bluewave said:

This would probably have been a minimum closer to 7 million sq km in a pre 2007 Arctic world. Zack Labe posted a great chart on how low the pressures were over the Arctic the last two summers. Lowest pressures since the 1990's. But extents well below those levels.

Another summer of predominately cyclonic (low pressure) conditions over the#Arctic polar cap (>65°N) --> cloudy and "cool" pic.twitter.com/7LySJd5pqN
 
DnbYcmtU0AItYY7.jpg-small.jpg.757efda5e690bf8e7eaaff1527fcda72.jpg

I remember someone had written an overview of the 2013 Arctic melt season and I can't find it now...but either way it showed how much the loss of multiyear ice had changed the Arctic. The 2013 summer was the coldest in the Arctic basin since 1996...but yet we still had a min around 5 million sq km, which was lower than any min pre-2007...despite some really warm years like 2005 or 2002. 

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16 minutes ago, ORH_wxman said:

I remember someone had written an overview of the 2013 Arctic melt season and I can't find it now...but either way it showed how much the loss of multiyear ice had changed the Arctic. The 2013 summer was the coldest in the Arctic basin since 1996...but yet we still had a min around 5 million sq km, which was lower than any min pre-2007...despite some really warm years like 2005 or 2002. 

Yeah, the 2017 Arctic Report Card showed how the loss of multiyear ice created a new normal over the last decade.

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Not sure if this has been discussed so excuse any redundancy -

I've accepted the notion smoldering underneath all this monitoring that the perennial ice is on a course toward extinction ... whether that reality is observed next year or decades away, notwithstanding. 

What I'm interested in is the "rate" of recovery over the seasonal transition.  Those modalities are perhaps more telling about the drivers and forces effecting a system than the scalar statuses.   

Many of these more impressive cold wave winters (that may or may not have had concomitant snow storm efficiency) were led off by fantastic recovery rates with sea ice expansion, as well, with land-based cryospheric metrics, during the preceding autumns.   

I think it is also less systemically observable over antiquity because passed decades did not have as much exposed naked sea-surface, having ice more enduring during warm months ...such that said rates more likely merely went unnoticed.  

So, it's supposition...but, I suggest a rapidity in areal ice recovery ... along with land-based numbers, can be telling signs for an ensuing winter's arctic contribution to modulating middle latitudes around the Hemisphere - notice I said 'Hemisphere' and not 'local-yoke's  backyard'... 

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That EC run last night -- oof. +4SD ridge. Even the EPS is +3SD at a week out with widespread +10-15C anomalies across almost the entire basin. The FV3-GFS is much the same. OP deterministics are of course even more extreme. This would be a pretty hefty ridge by mid summer standards, much less late Sep/early Oct.

Yet another year with an extreme autumn setup.

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1 hour ago, csnavywx said:

That EC run last night -- oof. +4SD ridge. Even the EPS is +3SD at a week out with widespread +10-15C anomalies across almost the entire basin. The FV3-GFS is much the same. OP deterministics are of course even more extreme. This would be a pretty hefty ridge by mid summer standards, much less late Sep/early Oct.

Yet another year with an extreme autumn setup.

Looks like a new positive 500 mb height record for this time of year over that region.

 

IMG_0250.thumb.PNG.92dcfde36bed7236f8dffb19ef03395f.PNG

 

 

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10 hours ago, bluewave said:

Looks like a new positive 500 mb height record for this time of year over that region.

 

IMG_0250.thumb.PNG.92dcfde36bed7236f8dffb19ef03395f.PNG

 

 

Chris, we've been setting records like this in different parts of the world's oceans for a few years now.  What year had our latest sea ice minimum and does it look like we could break that record this year (with a sea ice minimum as late as October for the first time ever?)

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7 hours ago, LibertyBell said:

Chris, we've been setting records like this in different parts of the world's oceans for a few years now.  What year had our latest sea ice minimum and does it look like we could break that record this year (with a sea ice minimum as late as October for the first time ever?)

This delayed freeze-up continues to be very impressive. The record ridging and warmth dropped the extent to the 3rd lowest on record behind 2012 and 2007 for 9-26.

IMG_0251.thumb.PNG.41ec7ded5ced77eb7b662049d40c1d2b.PNG

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9 hours ago, bluewave said:

This delayed freeze-up continues to be very impressive. The record ridging and warmth dropped the extent to the 3rd lowest on record behind 2012 and 2007 for 9-26.

IMG_0251.thumb.PNG.41ec7ded5ced77eb7b662049d40c1d2b.PNG

According to that the sea ice extent has been increasingly slightly in the last few days- so the minimum likely wont be in early October?  Is this still the latest we've ever seen the minimum, Chris?

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14 hours ago, LibertyBell said:

According to that the sea ice extent has been increasingly slightly in the last few days- so the minimum likely wont be in early October?  Is this still the latest we've ever seen the minimum, Chris?

This was the latest minimum so far on record tied with 1997. But the extent was much higher that year. The CPC issued an historic forecast for the the NW Alaska region due to the record warmth there. 

https://nsidc.org/news/newsroom/arctic-sea-ice-2018-minimum-extent

Arctic sea ice has likely reached its minimum extent for the year, at 4.59 million square kilometers (1.77 million square miles) on September 19 and 23, according to scientists at the National Snow and Ice Data Center (NSIDC) at the University of Colorado Boulder. The 2018 minimum ties with 2008 and 2010 as the sixth lowest in the nearly 40-year satellite record. September 23 is the latest day in the year the Arctic sea minimum has occurred in the satellite record—observed this year and in 1997.

https://www.arctictoday.com/open-warm-waters-off-arctic-alaska-spark-bold-forecast-warm-october/

The lack of sea ice off Alaska and the persistence of warm temperatures in the open waters there have set up an unusual weather situation — a near-certain forecast of significantly higher-than-normal temperatures for northwestern Alaska.

The National Oceanic and Atmospheric Administration’s Climate Prediction Center forecasts and 85 percent chance that northwestern Alaska will have temperatures significantly warmer than normal in October.

That is the “first time in recorded history” that the Climate Prediction Center has issued a probability above 80 percent, said Rick Thoman, climate science and services manager for the National Weather Service in Alaska.

“That is a really bold forecast, but all the pieces are in place,” he said at his monthly Alaska climate outlook briefing, held on Friday.

Sea-surface temperatures “are about as warm as they’ve ever been” in that region, hitting levels up to 4 degrees Celsius above normal in the northern Bering Sea and southern Chukchi Sea.

For fall and early winter, all of Alaska is expected to have weather that is both significantly warmer and significantly wetter than normal, according to the Climate Prediction Center forecast.

The wetter-than-normal conditions are part of a clear pattern in place since at least 2003 that is linked to sea-ice retreat, Thoman said.

The Climate Prediction Center’s forecast for a wetter-than normal early winter is influenced by an expected El Nino weather pattern in the North Pacific Ocean.

Thoman, a climate-science fixture in Alaska, is retiring from the National Weather Service this month and moving to the Alaska Center for Climate Assessment and Policy, a NOAA-funded program headquartered at the University of Alaska Fairbanks.

 

 

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3 minutes ago, bdgwx said:

Last night's Euro run was +4.25 SD at 168 right over the pole.

We've seen some nutty height anomalies over the Arctic at times in the past few freezing seasons, but this takes the cake. It's like taking the entire North Pacific atmosphere/airmass and ramming it into the Arctic.

Seeing some hints of an extended chinook event off the Kuskowim-Alaska Ranges and later the Brooks Range too. Definitely going to throw an extended brake on re-freeze. Might even see some drops (as Friv alluded to earlier).

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6 minutes ago, csnavywx said:

We've seen some nutty height anomalies over the Arctic at times in the past few freezing seasons, but this takes the cake. It's like taking the entire North Pacific atmosphere/airmass and ramming it into the Arctic.

Seeing some hints of an extended chinook event off the Kuskowim-Alaska Ranges and later the Brooks Range too. Definitely going to throw an extended brake on re-freeze. Might even see some drops (as Friv alluded to earlier).

What, if any consequences does this have for high lattitide blocking in October and even beyond,  in and around this region ? 

Also,  recently looking at the SST changes in the Gulf Of Alaska they are rising .

Would any of this warmth cause and or re-inforce a + PDO in developing in the month(s) ahead. 

 

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On October 4, 2018 at 4:53 PM, LibertyBell said:

2016 was pretty low too.  This year's is later than any of them though like you said.

This current Arctic temperature spike is now easily the warmest on record for the early part of October. Another example of Arctic amplification going off the rails.

http://sites.uci.edu/zlabe/Dox0x4RU8AAbota.jpg-small.jpg.94ae4a536fa4a5aaa3c232b3d4b462f2.jpg

Rick Thoman
@ AlaskaWx
Chukchi Sea ice extent from the @NSIDC passive microwave data has fallen over the past several days and as of October 05 is the third lowest since 1979: only 2007 and 2012 were lower. #Arctic #akwx #seaice @Climatologist49@ZLabe @CinderBDT907 pic.twitter.com/aZiqV4FWuT

 

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