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Arctic Sea Ice Extent, Area, and Volume


ORH_wxman
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Update:

We've reached the minimum on NSIDC area....area on 9/18 was 3.47 million sq km which is 270k higher than the minimum so far this year. Losing 270k after 9/18 hasn't happened in the record and there's no reason to think this year will be different looking at the weather up there. So the minimum will go down as 3.2 million sq km on 9/12.

 

Extent may or may not have reached the minimum yet. Extent on 9/18 stood at 4.68 million sq km. This is currently 60k above the minimum of 4.62 million so far this month, so there is still a low probability we fall back below that 4.62 million sq km number, but it's becoming more unlikely by the day. If extent rises over the next couple of days, we can probably safely call it.

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On 7/5/2022 at 9:48 AM, ORH_wxman said:

Update:

On 7/1, the NSIDC SIA sootd at 7.07 million sq km. Here's how other years compared on the same date:

2021: -70k

2020: -510k

2019: -450k

2018: +320k

2017: +10k

2016: -240k

2015: +130k

2014: +260k

2013: +340k

2012: -650k

2011: -210k

2010: -380k

2009:+640k

2008: +220k

2007: -400k

 

For the minimum Sea ICe Area prediction, we can use prior years' melt out from July 1st onward to estimate how this tear will turn out because there hasn't been much of a trend in ice loss after 7/1....the big trend has been prior to 7/1. We have maybe seen a slight increase in melt from 7/1 since 2007, so I will weight those years more.

Below is a table of how 2022 would turn out if it followed previous years' melt out from 7/1 onward....

 

image.png.881f7655db1d54ec04000ae2a38e71a7.png

 

For example, if we used 1989's ice loss from here on out, we'd finish at 2.66 million sq km. 2016 had the highest meltout beyond 7/1 on record, and would produce a final SIA min of 2.55 million sq km if we followed that path in 2022. You'll note that the record year of 2012 is only like 4th or 5th most ice loss from 7/1 onward which means most of the damage was done prior to 7/1. We can pretty much rule out a new record this season based on this data. We'd need to obliterate the post 7/1 loss record set in 2016 to achieve it. A top 3 lowest min is probably out too.....likewise, a top 3 highest min in the post-2007 context is likely out as well....though another 2010 from here on out would achieve it. All other post-2007 years would fail, however.

 

All that said, the average ice loss from 7/1 onward in the post-2007 era is 4.09 million sq km which would produce a 2022 min of 2.98 million sq km (7.07 million minus 4.09 million). I'm going to stick very close to this number and go with a final minimum of 3 million sq km +/- 300k. I might hedge a little higher if the forecast was colder on the Beaufort/CAA side over the next week but they will continue to see mild weather so I will stick with 3 million.

 

Final extent prediction is a lot harder than area because extent relies a lot upon compaction/dispersion which is really hard to forecast. But that said, usually something in the 3 million sq km range for area will produce an extent min on NSIDC of around 4.5-4.8 million sq km. So I will go with 4.6 million +/- 500k....I have larger error bars on the extent. (side note: JAXA extent usually comes in around 200k lower than NSIDC extent after their algorithm update post-2013....so I will not be using Jaxa to verify this prediction. Only NSIDC daily extent)

Update and verification of prediction earlier this season:

On 9/20, the NSIDC extent had risen to 4.75 million sq km which puts it 130k above the minimum of 4.62 million sq km several days ago. It is pretty safe to call the minimum at 4.62 million sq km. This extent is 7th highest (or 9th lowest) since 2007. Both 2017 and 2018 finished at 4.63 million sq km.....barely higher than 2022.

Area continues to rise too now at 3.6 million sq km, but we reached the minimum on that 9 days ago at 3.2 million sq km. The 3.2 million sq km area minimum ranks 5th highest since 2007....only 2009, 2013, 2014, and 2018 were higher.  The reason area ranked higher than extent was that the ice pack was more compact this season than other years like 2021 and 2017 which had lower area numbers but higher extent minimum.

 

The predictions quoted above were for area to finish at 3.00 million sq km (+ or - 300k) and for extent to finish at 4.6 million sq km (+ or - 500k). Verification fell within these predictions (and almost exactly for extent), so I am glad to see that the meltponding continues to be a very accurate predictor of minimum extent/area.

 

I don't do predictions for volume, but PIOMAS volume minimum has likely been reached as well at 5039 cubic km.....which is the 10th lowest in the record. It is the highest minimum volume since 2015.

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  • 3 weeks later...

Great job from the statistical Arctic sea ice modeling team. The early June forecast was just a little on the low side but still good for such a long lead time. It corrected higher as the months went on. So another September average extent in the 4s. This has become the new normal since 2007 with 11 out of the last 16 years in this range.

2022….4.87

2021……4.92

2020……3.92

2019……4.32

2018…...4.71

2017……4.87

2016……4.72

2015…..4.63

2014…..5.28

2013…..5.35

2012…..3.60

2011……4.61

2010…..4.90

2009….5.36

2008….4.67

2007…..4.28

 

 

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The NH annual mean extent for 2022 was 10.661e6 km2 per NSIDC. This is the highest extent since 2014.

The SH annual mean extent for 2022 was 10.647e6 km2 per NSIDC. This breaks the previous record of 10.749e6 km2 set back in 2017.

The Antarctic decline is unexpected. Per IPCC AR5 we were expecting sea ice to increase until at least 2030 and possibly even 2050 before significant declines started down there. If these kinds of declines continue we may need to start thread for the Antarctic region as well.

In terms of global sea ice area it's not looking good. We are still 0.5 to 1.5 months from the minimum and we're already at the 2nd lowest on record and easily smashing the record low for Dec. 31st.

QuqbPUH.png

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The biggest issue with using sea ice extent as a measurement of warming cycles is the obvious one. 

 

Reliable records in the arctic only began in the mid 1950s.  Then, with satellites later on, we were able to begin continuously measuring ice extent fairly accurately.  GPS has allowed for extremely accurate measurements.  

 

The problem with this data is that it only goes back an extremely short while into history.  To state, "the ice is at an all-time record low," must be put in context.  Record keeping is incredibly important, and in another 100 years, VERY SMALL trends may be apparent. It will take thousands, mayne tens of thousands of years of records to make sound predictions, concerning climate trends. 

 

It is of my opinion that one cannot honestly draw significant conclusions from such a short duration of records.  

 

Core samples already tell us more, as radio isotopes can be used to make deterministic conclusions about climate history.  Predictions based on short term assessment are not of sound science. 

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Arctic sea ice was likely lower during the Holocene Climate Optimum and almost certainly lower prior to the current ice age. It is a testament to the fact that given a big enough nudge not only can Arctic sea ice go lower, but it can entirely disappear. And I don't mean mean go "ice-free" in the summer with < 1e6 km2. I mean literally go to 0 km2 year round.

Anyway, per Walsh et al. 2016 (see also Walsh et al. 2019) Arctic sea is lower than at any point since 1850 AD.

d7BsGL4.png

And per Kinnard et al. 2011 Arctic sea ice is lower than at any point since 600 AD.

yvqwknl.png

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On 2/15/2023 at 5:33 PM, bdgwx said:

Arctic sea ice was likely lower during the Holocene Climate Optimum and almost certainly lower prior to the current ice age. It is a testament to the fact that given a big enough nudge not only can Arctic sea ice go lower, but it can entirely disappear. And I don't mean mean go "ice-free" in the summer with < 1e6 km2. I mean literally go to 0 km2 year round.

Anyway, per Walsh et al. 2016 (see also Walsh et al. 2019) Arctic sea is lower than at any point since 1850 AD.

d7BsGL4.png

And per Kinnard et al. 2011 Arctic sea ice is lower than at any point since 600 AD.

yvqwknl.png

The arctic can go ice free all year? Based on what evidence?

 

but but… Al gore said it would be ice free in 2008. Why isn’t it ice free now?

 

how gut hooked do you have to be to believe the arctic can be open water all year?

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The arctic can go ice free all year? Based on what evidence?
 
but but… Al gore said it would be ice free in 2008. Why isn’t it ice free now?
 
how gut hooked do you have to be to believe the arctic can be open water all year?

It was a swamp with alligators and palms during the Cretaceous.
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On 2/17/2023 at 9:19 AM, Wxdood said:
The arctic can go ice free all year? Based on what evidence?

Paleoclimate and paleontology records.

 

On 2/17/2023 at 9:19 AM, Wxdood said:
Al gore said it would be ice free in 2008. Why isn’t it ice free now?

The latest evidence suggests "ice-free" (defined in literature as < 1e6 km2) will first occur around 2050 (IPCC AR6 WG1 SPM pg. 16). This is the most aggressive prediction I've seen based on the broad evidence. It is more aggressive then the IPCC's previous of prediction of 2070 in the early 2000's and 2100 in the 1990's. The IPCC's predictions are based on a consilience of evidence approach and so adequately represents the scientific expectation. 


Regarding Al Gore...his prediction of 2013 (made in 2008) and then later 2016 was based on a single cherry-picked source that never said what Gore claimed. That source is Maslowski. Specifically Maslowski et al. 2008 and later Maslowski et al. 2013. I encourage you to read the publications yourself. In fact, Maslowski goes to great lengths warning his audience to be careful with predictions based on extrapolation of recent trends and even warns against taking dynamically modeled predictions (like from his NAME model) verbatim due to the large uncertainty and limitations with sea ice modeling in general at the time. And note that Maslowski said in response to Gore's statement "It’s unclear to me how this figure was arrived at. I would never try to estimate likelihood at anything as exact as this.” Let that be a cautionary tail to 1) discount scientific predictions coming from non peer reviewed sources and 2) always check the sources provided.
 

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This Winter.. seems to be more "normal", doing analog-research and other things throughout the Winter vs previous Winter's that were more "smoothed out through the Hemisphere". 2012, March 2012 is hitting pretty hard as an analog right now, and this was the last relative max, which I think we could accelerate toward this Summer. 

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On 2/17/2023 at 10:19 AM, Wxdood said:

The arctic can go ice free all year? Based on what evidence?

 

but but… Al gore said it would be ice free in 2008. Why isn’t it ice free now?

 

how gut hooked do you have to be to believe the arctic can be open water all year?

How do you believe all of those peat and fossil fuel deposits got there in the first place -- or fossilized tropical and sub-tropical forests?

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The study articulates concerns scientists have harbored since the record low noted in 2007 (and since broken in 2012). At the time, some wondered if it was the beginning of an epic collapse. That didn’t happen, but there was no significant rebound, either.

Researchers have been reluctant to be too declarative on potential changes to the Arctic sea ice system as a whole because there is so much variability in ice cover from year to year, Meier said. The new study could change that, he said.

“They make a pretty good case and put together a lot of data to say, yes, there is a fundamental change and we’re in this new regime,” Meier said.

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On 3/8/2023 at 11:32 AM, Stormchaserchuck1 said:

Ridging in the NW Pacific Ocean is reflecting a very far north Hadley Cell.

http://www.meteo.psu.edu/ewall/ENSHGTAVGNH_0z/ensloopmref.html

In principle ...the expansion of the Hadley cell is papered and legit ...

Personally, I suspect 'some' of the present/modeled observed heights across the N arc of the Pac basin may be related to La Nina "hang-over," however.

Only recently ( ... 3 or so weeks) entered the break-down phase of a collapsing La Nina scaffolding.  In fact, the SSTs/thermocline modulations along and E of the 3.4 region of the equatorial Pac have recently rapidly switched signs toward warming ... As CPC's methodologies and NCEP et al describe, they've issued their last Nina advisory for this evolution. We are presumed neutrality moving forward.  

However, during this delta window, there is a warm surplus - it's more of a default circumstance of residual west Pac warm anomalies, with recently established near or at neutral SSTs in the east - not the same as a +ENSO ... heh, call it a "La Nino." The atmospheric mechanics are not really there.  It just seems that after a 3 seasons of persistent Nina coverage, 2/3rds of the times representing clad coupling to the atmospheric circulation mode, it's too plausible that the ridging up there is geographically lagged by the west Pac forcing, ...while the new warming SSTs in the trop E are an indirect indicator that the circulation mode overall is then drawing the heights farther E.  

I'm curious if that effects the spring R-wave geometry over N/A...  Conflicting signals for early heat ( or not..).  The residual Nina favors higher heights over the eastern 1/2 of mid latitudes in April-June.  But drawing heights across the N/Pac could either drop the field over the Midwest, or... if it got overwhelming, the whole thing could go 2012-like.

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I think the 2012 analog is a good one. The La Nina was not effecting last April-November, as we had mostly +PNA during that time. It seems that for the last few weeks, the SE ridge in the US has been blasting, and it has been interesting to watch models over and over trend toward a correlating -PNA(Aleutian ridge), which makes me think that the whole -PNA system is part of this ongoing Hadley Cell expansion, vs a mechanic like it being ENSO-driven, at least right now. As time passes other things clear, and 2012 keeps popping up. 

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Based on these cooler May temperatures across the Arctic, the melt pond season is probably getting off to a slower start. This is what the melt pond model uses to project a September minimum when the data is released in June by Will Gregory CPOM. So this could mean that the 2012 record will be safe for another year. It’s the opposite of the May record warmth which lead to the big melt year in 2020.

 

6793FCD2-428F-4E0E-8694-9D423765A972.gif.b70196672427a6642901b4724370c670.gif
DBC17DA2-11B3-4EF9-A707-E3B7F2FFC244.png.19e8d3cc0facfbad9a554a4f6875fa84.png
https://ocean.dmi.dk/arctic/meant80n.uk.php

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