Poll: Nares Strait closure in 2018

[Tor Bejnar]

Any bridge that 'counts' must have a leading edge that remains intact for at least 3 days within (and totally across) Nares Strait or 6 days within the Lincoln Sea.  If some downstream ice peels off (not including new fast ice), the date is re-set. (Some consider potentially stable ice north of the Lincoln Sea Polyna not to be an arch, but it will be considered to be one for this poll's purposes.)

The first day of bridge/arch formation determines the bridge's formation month.

A big thick ice floe that gets stuck for 3 days on an island (for example) counts if no ice can sneak around, etc.

A few 'old' posts that might assist you:

Nares Strait is often (always? in recent years) open at least into December (but I don't have the statistics).  In 2006-07, it never closed.  I understand that in other years no effective bridge formed, too.  Neven, in 2013, recommended The Broken Bridges of Nares for those who want to learn some history of Nares ice bridges.

Did some quick research about approx. breakup times, southern "arch" in Kane Basin unless noted otherwise:
2007 - No arches formed.
2008 - June 10th(?)
2009 - No southern arch. Northern arch broke around June 30th.
2010 - July 10th
2011 - July 5th.
2012 - June 30th.
2013 - July 10th.
2014 - June 20th.
2015 - July 5th.
2016 - June 30th
2017 - No southern arch. Northern arch broke around May 10th.
...

...
Although ice arches normally form by about April, I don't expect to see one form this year: the ice is too thin, weak, young and mobile.

For the last three days (2/2 - 4/2) the "arch" at the Lincoln Sea seems to be stationary. Will this stability prove to be long-lived? Past experience this month says no, the date says maybe yes.

I couldn't find a list of ice bridge formation dates.  Any help out there?

[Tor Bejnar]

No comments, but 8 votes, just in case you're the sort of person who doesn't want to visit a "nothing's happening" thread.   

[johnm33]

Tor, I suspect a late surge in the freeze season/extent may occur so i went with march, and think lincoln, but it's only a guess, i've made some good guess' more bad but this is the first year i've found it hard to form a view about what's happening.

[oren]

It's typically in February, so I went for that.
In looking for past closure dates (in Nares thread, the best place to search), I think a 3-day criterion is too short though. I would suggest a 7-day threashold.
Check this 2015 animation by Wipneus, where Kane closed around Jan 29th, opened almost a week later due to wind from the south, and finally closed around Feb 15th.
Something similar happened at the Lincoln entrance, it held for a few days and then broke apart.

https://forum.arctic-sea-ice.net/index.php/topic,176.msg44954.html#msg44954

[Tor Bejnar]

Thanks, oren, for sharing your concern.  I'm keeping the 3-day/6-day 'rule'.  I think it very possible  the only ice bridge we see this year will be the temporary sort (associated with a period of southern winds).  I recall watching short-lived bridges in both Kane Basin and above the Lincoln Sea Polyna form, only to have a piece of the edge peel off, then 'stick' for a couple days, then peel off some more.  (I looked for a list of closing dates, but didn't find one - I know I've seen one!)

By the way, I voted for a March bridge.  Interesting that the 15 votes are evenly spread between three bins.  (You can always vote to see where the distribution is, then remove your vote because voting in polls like this is beneath your dignity.     )

[Neven]

No comments, but 8 votes, just in case you're the sort of person who doesn't want to visit a "nothing's happening" thread.   

I'm sorry, Tor, I just don't know what to vote!

I'll just go for 'not this year'.

[Tor Bejnar]

Putting it off, eh, Neven? 

[Pmt111500]

Voted for March. There ain't no solid reason for this. The possible diversion of North Atlantic Drift west of Greenland due the stop of Greenland Meltwater intrusion to Nares could reverse the Nares flow and switch the Beaufort Gyre anticlckwise could happen anytime and could apparently stop ice movement or make it even retreat in Lincoln. 6-days solid line of thin ice happens so regularly in inner seas with little mobility like Baltic aren't of course a good place to compare.

Oh, horrible grammar. Sorry, can't write properly from phone.

[Paddy]

Gone for Feb, as Oren says that it's typical, but tbh I really have no idea.

[Tor Bejnar]

No ice bridges in January, so each member of the voting public remains potentially accurate in their prediction.

[Tor Bejnar]

Thanks b.c. (on the Nares Thread) for reporting the bridge in Kane Basin. (I haven't been looking for a couple weeks.)

Looking at DMI Sentinel images, I see the arch on February 28 and onward, only on March 1st, it is clear some of the arch peeled off (moving the arch up-stream, and disqualifying the February start date).  So we have March 1 and March 2.  So, will we have March 3 for eight winners?

Sorry, February voters; but it was sure close!

[Tor Bejnar]

The Kane Basin arch continues to hold - unchanged between March 1, March 2 and March 3 Sentinel images published by DMI.  WorldView shows the bridge on March 2 and 3 through light clouds.

Now, does this constitute "3 days" or is this just "48 hours"?  Do we need another day to declare?

[oren]

The Kane Basin arch continues to hold - unchanged between March 1, March 2 and March 3 Sentinel images published by DMI.  WorldView shows the bridge on March 2 and 3 through light clouds.

Now, does this constitute "3 days" or is this just "48 hours"?  Do we need another day to declare?

Be conservative, wait another day

[Niall Dollard]

Looks like we have closure !

[Tor Bejnar]

Thanks for creating and posting the GIF, Niall.

Now, will this bridge hold until spring?  Or will it break in a day or two?

[oren]

Thanks for creating and posting the GIF, Niall.

Now, will this bridge hold until spring?  Or will it break in a day or two?

A. Mar 1 is a good date, it gives an "almost" satisfaction to the Feb voters, in addition to paying the bets of the Mar voters.
B. I have a feeling, once it sets in, only wind reversal can shake it hard enough.

[Tor Bejnar]

Thanks for reminding me oren, that there may be bets to pay off.  I told everybody who asked me to send their bets via Neven's "Support and Donate" button on the ASIB and he'd pay them their fair share.  I'm one of the March winners, but I'll donate my winnings to the cause.

[Tor Bejnar]

Those who wanted a more stringent 'bridge for a week' (instead of a mere three days) have it.  The March 1 bridge has held, per DMI published imagery.