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Topics - Tor Bejnar

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Also, from the July 3 post:
Furthermore, a new sophisticated computer model of Petermann Gletscher reveals that the loss of this large “still attached” ice island is already gone from the glacier in terms of the friction that it provides along the sidewalls. Another way of putting this, all it takes is a little wiggle or bump and the separation will become visible. Dr. Martin Rueckamp just published this study in the Journal of Geophysical Research.
JGR link
My Petermann posts here and here show the mid-tongue (or mid-shelf or mid-glacier) lateral crevasse extending southwestward and crevasses extending from the SW edge extending into the tongue during the past year.  Thomas Barlow showed the mid-tongue crevasse definitively connected to a crevasse coming from the NE edge of the tongue (although it was apparent in January with other sensors).  Other posts in the Petermann thread show the various crevasses widening.

So, when will an ice island completely (definitively) break from the Petermann Ice Shelf at the mid-tongue crevasse?

A calving boundary that does not include the mid-tongue crevasse doesn't count.  By "definitive" I mean clear satellite imagery that shows a continuous crevasse between the shelf and the new ice island in the area southwest of the mid-tongue crevasse reaching the SW edge of the tongue.  (There is one already northeast of the mid-tongue crevasse.)

(Just in case there are any questions about where I mean, tomorrow I'll post an annotated image of the Petermann Ice Shelf.)

The less sure you are of when the event will happen the more bins you can choose, up to 3.  As it is all a guess (unless it cracks within a fortnight), we should all probably choose 3 bins! Votes can be changed.  Of course, kudos to the person who votes only one bin and correctly!  In case it breaks at a bin edge, time is GMT (with which some satellite images are tied).

Arctic sea ice / Poll: ASI JAXA Minimum Extent range of possibilities
« on: July 07, 2019, 04:06:03 PM »
All 'guess the minimum' polls to-date have been to guess the minimum (or maximum) of something.  Here, we are to exclude the ranges (bins) we consider not possible this year.  There are 12 bins, and you can vote 'against' up to 11 bins.

For example, if you think the Arctic Sea Ice Extent (ASIE) will be 4.0 million km^2 [= km2] at minimum, you'll accept it might be a little more or a little less, but definitely not a lot more or less, definitely not a blue ocean event (BOE, for this poll's purpose = under 1m km2), therefore you will select (vote for) [something like] the top 3 bins (5.0 and up) and the bottom 4 bins (2.5 and under, leaving 4 bins you consider possible (2.5 - 5.0).  The more confident you are, the more bins you will select.  E.g., if you 'know' there will be a BOE, you'll select the top 10 bins.

Functionally, when will it (first) be possible to sail a non-icebreaker all along the Alaskan (northern) coast (not counting fast ice) this year?
No changing of votes, and to be a 'winner' (at the expense of Arctic ice) with Option 1 [< June 1], you have to have posted your guess prediction before it [ice lifting off coast] actually happens.  I'll let Neven be the impartial determiner of when the Alaskan coast area is deemed clear enough of ice.  (If he doesn't post it in this thread, we'll figure out his opinion from his postings elsewhere.)

For those interested in what happened in the Beaufort, back in 2016 (so as to compare to this year's situation), I wrote about it extensively on the ASIB. Here's a blog post from May 21st, with links to previous blog posts in the first paragraph.

One thing I wondered about back then, and do again now:

The other thing is that there is actually not that much ice left between the large polynya (expanse of open water) in the Beaufort Sea and the smaller one in the Chukchi Sea:

Once this ice is gone, there will be open water all along the American coast of the Arctic Ocean. My guess is this could happen within two weeks or maybe even faster, which would be extremely early, given that the earliest time this has happened in the past decade (and probably much, much beyond that), was between July 1st and 7th in both 2009 and 2011.

My guess turned out to be wrong. It also took until the first week of July for open water to take over all along the Alaskan-Canadian coast.

But how about this year? Here's a comparison:

The maps look very similar, so much so that one would be tempted to think there is something causing the ice to stay glued to the coast, all the way up to Utqiaġvik. But there's no "Chukchi polynya" now, with open water all the way to the Pacific and far into the Chukchi, meaning there is less ice to be blown back towards the coast, should the winds turn.

And the winds are another similarity. Both the weather forecast back then and the one this year show a change in the set-up that caused the early Beaufort opening, around the same time. However, this year there may be a return to that set-up next week.

So, wondering if there will be open water all along the Alaskan-Canadian coast before July this year...

Greenland and Arctic Circle / Old ice moving through Nares Strait
« on: March 01, 2019, 05:04:30 PM »
Floes entering Nares Strait take between a week and two month (plus?) to go the 500 km to Baffin Bay (when the Strait is open).  The arch around the Lincoln Sea Polynya has been stable for a couple of weeks, basically, so (basically) all the mobile thick ice ("old") in the Lincoln Sea has now flushed into Nares Strait.  The last bits are circled in the image below (DMI image dated 2019-02-27). 

So, will the 'old' ice that recently entered Nares Strait get to Baffin Bay before new 'old' ice enters the Strait?

"Yes" will be correct if the current Lincoln Polynya arch holds on long enough (How long will be enough?) or a bridge forms in the Kennedy Channel above these circled bits of 'old' ice before more recently mobilized thick ice gets to the Strait during March or April 2019 [edit: and no southern bridge forms …].

"No" is split. 
  • Either the Lincoln Polynya arch breaks soon enough so that at least one floe of thick ice (much older than the two-week old ice currently in the polynya) enters Nares S. before the circled bits pass beyond Smith Sound or
  • these circled bits get stuck in Nares Strait for the rest of the winter due to the formation of an ice bridge (arch) downstream (at which point all the ice in Lincoln Sea will be 'old' enough to count as 'old'
"Maybe so" will be correct if a southern bridge holds the circled bits for 50 days or more, but a northern bridge holds back all Lincoln Sea ice until after the southern bridge breaks and all the circled bits flow into Baffin Bay.

Identifying the date ice across Kane Basin near its northern end moves (showing cracks) will be the goal.  (Ice bridges further north in Nares Strait may remain in place.  The first or current southern ice edge may break long before ice moves in the northern part of Kane Basin.)

This inspired me:
It looks like the impact of "no Fram" due to warmth will imminently entail the re-opening of Nares for export. Massive cracking extending towards it as of yesterday. Probably won't take much to break the arch and start early transport of MYI toward Baffin.

Some may want to know some history:
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.

We can all win if it breaks this next week or so, as votes can be changed!  ;)

Greenland and Arctic Circle / Poll: Nares Strait closure in 2018
« on: January 12, 2018, 09:51:28 PM »
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?

Arctic sea ice / JAXA Arctic Sea Ice Extent Ranking - end of 2017
« on: December 15, 2017, 07:19:55 PM »
... Extent still 2nd just - see image to see how predicting outcome even to Dec 31 looks like a mugs game...
Yah:  somewhere between (or including) 1st and 10th place on Dec. 31 or Jan. 1, I'd say.  Poll anyone?

Third looks like the lowest it could reasonably attain (after 2016 and 2010).  The growth is starting to pile on, so 15th is not out of reach, as the difference between 3rd and 15th is less than 1st and 3rd.
Refer to the 2017 sea ice area and extent data for general discussion, or here if you want to influence other voters  :).

The poll results will only show after the poll has expired in 9 days (about now on Christmas eve, by my calculation), but you may change your vote until then.  (I wonder what the effect of no-instant gratification will be.)  [Edits:  Rank of 1 is lowest extent.  "Remove vote" works - I've already changed my mind.  I just noticed my typo:  two options for choosing 12th place!]

Greenland and Arctic Circle / Nares Strait Flushing Poll
« on: July 07, 2016, 03:29:33 PM »
Every year after the Nares Strait ice bridge(s) break*, it takes a while for the ice to flush out.  Once the ice gets going though, it can zip through.
Several years ago, Moira Dunbar published the attached table.

According to an internet calculator:
.83 m/sec  = 72 km/day
.59 m/sec = 51 km/day
.24 m/sec = 21 km/day

Nares Strait is just over 500 km long, so ice 'never' travels the distance in less than a week.

This poll will remain open until July 27.
* - No ice bridge formed during the winter of 2006-7.

Policy and solutions / Law of the Sea Treaty
« on: October 01, 2015, 02:22:30 PM »
I knew about the "Law of the Sea" Treaty as it was being developed in the 1970's and early 1980s, and have been dismayed that the U.S. government never ratified it. As a brief introduction, here is some background from the UN Law of the Sea Treaty site.

The Law of the Sea Treaty, formally known as the Third United Nations Convention on the Law of the Sea, or UNCLOS III, was adopted in 1982.  Its purpose is to establish a comprehensive set of rules governing the oceans and to replace previous U.N. Conventions on the Law of the Sea, one in 1958 (UNCLOS I) and another in 1960 (UNCLOS II), that were believed to be inadequate.

Negotiated in the 1970s, the treaty was heavily influenced by the "New International Economic Order," a set of economic principles first formally advanced at the United Nations Conference on Trade and Development (UNCTAD).  That agenda called for "fairer" terms of trade and development financing for the so-called under-developed and developing nations.

Another way the New International Economic Order has been described is "redistributionist."

The Law of the Sea Treaty calls for technology transfers and wealth transfers from developed to undeveloped nations.  It also requires parties to the treaty to adopt regulations and laws to control pollution of the marine environment.  Such provisions were among the reasons President Ronald Reagan rejected the treaty in 1982.  As Edwin Meese, U.S. Attorney General under President Reagan, explained, " was out of step with the concepts of economic liberty and free enterprise that Ronald Reagan was to inspire throughout the world."

Here are exerts from an article in E&E (subscription required); an internet search doesn't turn up any real recent articles about the Law of the Sea, but there is plenty not-quite-so-current articles to look at!
As ice melts, Law of the Sea increasingly relevant -- expert
Ariel Wittenberg, E&E reporter
Published: Thursday, October 1, 2015

The United States risks missing out on economic opportunities in the Arctic because of Congress' failure to ratify the U.N. Convention on the Law of the Sea, a retired Navy official told congressional staffers yesterday.

Speaking at a briefing about melting Arctic ice, retired Rear Adm. David W. Titley noted that in not ratifying the convention, the United States forfeited its right to make claims to its extended continental shelf.

"We have the data, we know what our extended continental shelf claim would be under the convention, but we haven't ratified it," he said at the briefing, which was hosted by the National Center for Atmospheric Research. "That is essentially money on the table that we are leaving there. There is a lot of undersea land that we are simply not claiming."

Though the United States generally follows the convention and respects decisions made by the United Nations regarding which countries' claims to honor, America cannot give its input to the official decision.


Titley was one of four experts speaking at the briefing, which focused on explaining how a melting Arctic could affect the greater United States.

Much of the briefing reviewed scientific data proving that Arctic ice is melting and that man-made climate change is causing it. Researchers Jennifer Kay of the University of Colorado, Boulder, and Julienne Stroeve of the National Snow and Ice Data Center explained why multiyear ice is more stable than single-year ice and how Arctic ice melts faster as the Earth warms due to positive feedbacks.

At one point, a member of the audience asked, "If Arctic ice has melted in the past, why do we care about stopping it now?"

UCAR President Michael Thompson answered, "It's not that the climate hasn't changed before. But for all of human civilization we have had this Goldilocks period of climate stability relative to what the Earth can do, and that is now changing and we know why. We are essentially embarking on an experiment with 8 billion people and figuring out how we are going to feed them and provide electricity in an environment that we have literally never seen before."

Arctic background / Psychology of Climate Change Denial
« on: July 01, 2014, 06:29:44 PM »

I regularly visit this blog that "explores the topic of the psychology of climate change denial - with observations and anecdotes about our weird and disturbed response to the problem."

I invite folks to react to Dr. Marshall's perspectives and to include references and discussion of this topic from other sources.  (I know I've read relevant things on Skeptical Science, such as

Latest entry on Dr. Marshall's blog:
George Marshall @ 12:57 pm

I was recently privileged to speak on a panel at the British Library about the peculiar lack of public discussion about climate change in areas damaged by extreme weather and the tendency for people to interpret these impacts in terms of their own politics and worldview.

According to a new report, after 2047 every year -even the coolest- will be hotter than the hottest years ever recorded. This deadline offers an original and potentially very useful new frame for climate change that breaks with the history of environmentalist deadlines and brings a sense of proximity, and a narrative of a journey that leads to an irreversible transformation.
      Climate Change Denial blog (

This new report is in Nature:  "The projected timing of climate departure from recent variability"
Ecological and societal disruptions by modern climate change are critically determined by the time frame over which climates shift beyond historical analogues. Here we present a new index of the year when the projected mean climate of a given location moves to a state continuously outside the bounds of historical variability under alternative greenhouse gas emissions scenarios. Using 1860 to 2005 as the historical period, this index has a global mean of 2069 (±18 years s.d.) for near-surface air temperature under an emissions stabilization scenario and 2047 (±14 years s.d.) under a ‘business-as-usual’ scenario. Unprecedented climates will occur earliest in the tropics and among low-income countries, highlighting the vulnerability of global biodiversity and the limited governmental capacity to respond to the impacts of climate change. Our findings shed light on the urgency of mitigating greenhouse gas emissions if climates potentially harmful to biodiversity and society are to be prevented.

Arctic background / USCGC Healy: scientific missions to the Arctic
« on: July 12, 2013, 04:31:36 PM »
United States Coast Guard Cutter Healy has left Seattle again.  Is the icebreaker headed north or is this just another sea trial?  Or do we care?  Magma wrote on July 3, 2013 in the ASIB - Problematic predictions 2
Based on the planned 2013 scientific missions, this year's route of the Healy may be of less interest to those interested in Arctic sea ice than its 2012 tracks were.
But the mission schedule at denies me access ('homeland' security?).

ship position:
ship webcam:
ship information:

old ASIB threads focused on the Healy:


edit Neven:

Vergent had also opened a USCGC Healy topic in the Arctic Sea Ice subsection along with these images:

Quest through the Pole: Sailing the Arctic, from Barrow, Alaska to Spitsbergen, Svalbard
Summer 2013

From their blog:
  • 8-Jul-2013   Baboushka on her way to Spitsbergen!
    Sebastien and Vincent left Barrow at around 4pm on July 6th, and sailed 6 nautical miles in free water from Point Barrow before reaching ice and had to decipher: lands of recent thin ice, blocks moved by tidal current, and large slabs with high pressure ridges across which they finally decided to push Baboushka during a few hours before stopping for setting up the "night" camp. ...
  • 10-Jul-2013  [Bing translation] Today, the path of the pole offers fog and blocks in all directions, it is chaos with just water to bathe when blocks on which we walk flow or they capsize. The boat is very busy at the beginning of expedition, it suffers and suffering men.It is eager to find more favourable conditions. Otherwise all is well on edge.

Arctic background / Arctic Maps
« on: July 05, 2013, 03:20:56 PM »
The first map of the Arctic that I found on the internet that included a scale was this National Geographic map:  (The scale is in the upper left corner, to which you may need to scroll.)

There is a Google Map of Greenland (and Nares Strait) with lots of location names here on the ASIF:,277.0.html.  This thread has other Greenland area maps referenced as well.

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