Summer Atmospheric Circulation Anomalies over the Arctic Ocean and Their Influences on September Sea Ice Extent: A Cautionary Tale

By stoat on August 15, 2016.

Summer Atmospheric Circulation Anomalies over the Arctic Ocean and Their Influences on September Sea Ice Extent: A Cautionary Tale (Mark C. Serreze, Julienne Stroeve, Andrew P. Barrett, Linette N. Boisvert, DOI: 10.1002/2016JD025161) says "sea ice is complicated". Or, in more detail:

Numerous studies have addressed links between summer atmospheric circulation patterns and inter-annual variability and the downward trend in total September Arctic sea ice extent. In general, low extent is favored when the preceding summer is characterized by positive sea level pressure (SLP) anomalies over the central Arctic Ocean north of Alaska. High extent is favored when low pressure dominates. If such atmospheric patterns could be predicted several months out, these links provide an avenue for improved seasonal predictability of total September extent. We analyze de-trended September extent time series (1979-2015), atmospheric reanalysis fields, ice age and motion, and AIRS data, to show that while there is merit to this summer circulation framework, it has limitations. Large departures in total September extent relative to the trend line are preceded by a wide range of summer circulation patterns. While patterns for the four years with the largest positive departures in September extent have below average SLP over the central Arctic Ocean, they differ markedly in the magnitude and location of pressure and air temperature anomalies. Differences in circulation for the four years with the largest negative departures are equally prominent. Circulation anomalies preceding Septembers with ice extent close to the trend also have a wide range of patterns. In turn, years (such as 2013 and 2014) with almost identical total September extent, were preceded by very different summer circulation patterns. September ice conditions can also be strongly shaped by events as far back as the previous winter or spring.

Meh. I haven't actually read the paper itself, of course.

Speaking of which, the current state is unexciting:

A new record is off the cards. It might scrape second, but I doubt it. Could be 3rd, 4th, or even 5th1 just possibly.

Notes

1. Or something else since, as I forgot by CR notes, that graph doesn't have all years on it.

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>"or even 5th just possibly."
above 4.28 seems fairly easily possible. Made me wonder if you realised 2007 and 2008 are not shown on graph above.
2012 3.18
2007 4.07
2015 4.26
2011 4.27
2008 4.5

4th seems unlikely - narrow range
6th or higher perhaps not impossible yet but maybe current low pressure will make it out of range.

[Ah not I hadn't realised that. You can see how far off the pulse my finger is :-) -W]

Well, cast off and motor away to the Northwest Passage.

Tamino has some history.

https://tamino.wordpress.com/2016/08/16/crystal-serenity/

And a bit from the CBC.

http://www.cbc.ca/news/canada/north/crystal-serenity-arctic-hamlets-pre…

In a decade, I'd guess this will be routine, and lower priced. Still, will take a month, and wouldn't appeal to the oldest range of cruise ship passengers, and not as much to the working age, due to limited vacation time.

By Phil Hays (not verified) on 17 Aug 2016 #permalink

The point to "giant floating gin palace" isn't the same for every passenger. It can be a way to get someplace that isn't easy to get to: such as the Arctic or a total solar eclipse in the middle of the ocean. Yes, for more money, higher risk and with rather worse food one might take a 10 meter sailboat there...

Vishop: 2016 (4.97 million km^2) is just about tied for second with 2007 (4.95 million km^2).

Ice is looking pretty ragged.

So what are odds that this year will not "scrape" 2nd?

[Could go either way, but the odds are on nothing exciting happening I'd say -W]

By Phil Hays (not verified) on 20 Aug 2016 #permalink

4,811,887 km2 so bound to go under 4.8. While staying very flat and then strong rise at end of September may give a very slight chance, intense low pressure is highly likely to cause rapid drops instead.

As ADS/NIPR hasn't shown data since 23 Aug, NSIDC daily data show:
2016, 08, 25, 4.850
2016, 08, 26, 4.691
ftp://sidads.colorado.edu/DATASETS/NOAA/G02135/north/daily/data/NH_seai…

Some area measures put us closer to 2012 and with the weather I don't see any way the extent is going to be surprisingly flat then rise a lot at end of September to put monthly average above 4.8.

long way above
2012, 08, 26, 3.906
While some more big drops may occur 4.7 is a long way above 3.1 so can't see that happening either.

There is room for large compaction drops in the area around the pole (N85 to 90) and with the current weather patterns we could see some large drops bringing us closer to 2012.

Getting down much lower that 2012 in extent will take something we really haven't seen before, but that's what watching the arctic has been about the last 10 years :)

I'm interested to see what PIOMAS comes out with for volume numbers at the end of the month. I think it more likely than not we set a volume record.

By Kevin O'Neill (not verified) on 27 Aug 2016 #permalink

Another cautionary tale.

How predictable is the date of an ice free Arctic ocean?

https://www.carbonbrief.org/guest-post-predictable-first-ice-free-arcti…

["In our new study, published last week in Geophysical Research Letters, we consider whether it’s possible to pin this down to a specific year". This is definitely a stupid question, because the answer is clearly "no". Fortunately, they are misrepresenting their own paper. Which whist not as stupid as they suggest, does look to be very much of the "infilling" variety and (sorry) rather pointless -W]

By Phil Hays (not verified) on 27 Aug 2016 #permalink