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28-09-2019, 22:05   #16
Oneiric 3
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Cheers mon!
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18-10-2019, 03:28   #17
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The cross Arctic channel for shipping closed in with the ice pack yesterday approaching the Laptev Sea. A real pace now to the increase in the sea ice.





Not long now fella


Last edited by Kermit.de.frog; 18-10-2019 at 03:58.
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19-10-2019, 20:42   #18
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Arctic sea ice volume charts now updated with the September (annual minimum) figures. Flat trend over the past decade, the most prolonged of the satellite era, but you won't read that anywhere.



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File Type: png Sea ice September volume.png (10.5 KB, 1754 views)
File Type: png Sea ice September volume 2010-19.png (8.1 KB, 1747 views)
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20-10-2019, 21:55   #19
pauldry
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Yes but its lowest JAXA on record currently by over 300k. Id say the reason its stayed flat in the past decade has been that a lot of the final multi year ice has been thinning. It will be interesting to see if it flatlines in the following decade. I severely doubt it and it will probably settle in the 3s in that decade
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20-10-2019, 22:33   #20
Gaoth Laidir
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Quote:
Originally Posted by pauldry View Post
Yes but its lowest JAXA on record currently by over 300k. Id say the reason its stayed flat in the past decade has been that a lot of the final multi year ice has been thinning. It will be interesting to see if it flatlines in the following decade. I severely doubt it and it will probably settle in the 3s in that decade
Thinning would be accounted for in the volume figures. It remains to be seen what happens next.

On another note, the total annual Greenland melt area has shown a similar hiatus, with in fact a notable decrease in melt area over the past decade. Figures from here.




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File Type: png Greenland melt area 2010-19.png (13.3 KB, 1235 views)
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20-10-2019, 22:58   #21
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Where is the "heat energy " going to then if the sea ice is stabilised? Is that why we ( in ireland anyway) are getting mildish winters, because of the gulf stream holding more of its "heat"? Do you think the polar vortex is getting more stable as well at this time of the year on a decade by decade timeframe?
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20-10-2019, 23:34   #22
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I think its rubbish to suggest the Arctic is stable. There are scarier facts behind the figures. As I said the Jaxa extent is the lowest on record and in many months over the past 5 years it has been the lowest on record. Its just that when September has come a lot of melt out is done and we are left with similar extent figures as before. This year was the 2nd lowest extent on record but in the record year there was a cyclone. The trend is down and by 2050 there will likely be little or nothing ice wise in the arctic in Summers end
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21-10-2019, 07:33   #23
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Quote:
Originally Posted by pauldry View Post
I think its rubbish to suggest the Arctic is stable. There are scarier facts behind the figures. As I said the Jaxa extent is the lowest on record and in many months over the past 5 years it has been the lowest on record. Its just that when September has come a lot of melt out is done and we are left with similar extent figures as before. This year was the 2nd lowest extent on record but in the record year there was a cyclone. The trend is down and by 2050 there will likely be little or nothing ice wise in the arctic in Summers end
So are you saying that the annual extent curve has changed shape and we're reaching the minimum earlier?Because we haven't. I posted the graphs before and 2019 is not the lowest.

Extent is one thing, the actual amount of ice there is another. Where 2019 falls is neither here nor there. If it's close to the record low (volume or extent) is not surprising, as a flat trend means that any year within that period could be close to the minimum. The fact still remains that the trend is flat (for now, anyway) but not one report I've seen has mentioned that. They're now down to quoting each year's rank instead of the trend. The AMO appears to be the main driver of Arctic ice changes.
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24-10-2019, 11:39   #24
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Quote:
Originally Posted by pauldry View Post
I think its rubbish to suggest the Arctic is stable. There are scarier facts behind the figures. As I said the Jaxa extent is the lowest on record and in many months over the past 5 years it has been the lowest on record. Its just that when September has come a lot of melt out is done and we are left with similar extent figures as before. This year was the 2nd lowest extent on record but in the record year there was a cyclone. The trend is down and by 2050 there will likely be little or nothing ice wise in the arctic in Summers end
Agreed, but these are not linear systems. There is a significant possibility of an ice free summer before 2030, maybe as soon as 2025, resulting in a massive spike (as much as 0.6 degrees) in warming due to an increase in permafrost methane. Once that happens the climate dominos start to fall.
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28-10-2019, 12:44   #25
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Arctic temperatures for October (full month except for 2019 which is up only up to the 27th) as per the Danish Met Office (DMI)



As of yesterday, the 2019 October mean stands at -10.98c, which ranks it the 4th warmest in the series (warmest was 2018). Another point to note is that there is missing data from between the 2nd and 8th this year on the data set, so this was filled in with a computed linear progression between the 6.04c on the 1st to -8.63c on the 9th. Not perfect but unlikely to distort the overall mean value from what it would have been if the data was available.

Data in graph is centered on the 1961-1990 October average. Black line represents the 10 year rolling average.

Source: DMI.
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29-10-2019, 22:23   #26
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A couple of days data yet to go, but looking increasingly probable that this October's Arctic sea ice extent will come in the lowest on record, or at least since 1979, when records seemed to begin.



Chart source: DMI

Last edited by Oneiric 3; 29-10-2019 at 22:27.
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30-10-2019, 12:31   #27
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Interesting. Parts of Denver could potentially achieve it lowest October temperature before the month is out:

https://www.denverpost.com/2019/10/2...ldest-october/

The still standing record of 1.0f occurred back on October 29th 1917. Looking at the reanalysis maps. the Arctic, the source of the intense cold back then, just as it is this time around, was much colder back then than it currently is now.

Current map (850 hPa temps)




Reanalysis map back on October 29th 1917:



Not only was the source of the cold outbreak over N. America much deeper back in 1917, but it was also far closer to the north of the Continent.

Yet back to the present, we have these potentally record breaking low temps coming from a source that potentially record breaking high for the time of year. Current temp anomaly map from C.R:


Something does not really add up here.
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30-10-2019, 12:36   #28
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Currently -14c there at 6.30am, I live in the wrong place.
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03-11-2019, 17:56   #29
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Daily sea ice concentration for October 2019 from NISDC/NASS. Orange line represents the 1981-2010 median extent.
(Large gif file so may take a short while to load)

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04-11-2019, 09:18   #30
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What is the significance of an average to 2010? Why not just have the average to last year?
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