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Neven

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Re: Northwest Passage thread
« Reply #200 on: August 01, 2016, 11:00:28 PM »
It'd be cool to have a list with dates from 2005-now like Quantum did, not just for the NWP, but for the NSR as well. I'd put it up on the blog as a reference.

What sources would be best to use? It would preferably be one that spans the entire period. We have the Uni Bremen SIC maps that Quantum used. Those maps from the Canadian Ice Service would be more detailed, but I'm not sure if there's an archive.

Precise definitions of the different NWP routes - like Quantum did - would be useful too. I know there's a paper out there somewhere doing something similar. I'll try and find it.
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Reggie

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Re: Northwest Passage thread
« Reply #201 on: August 01, 2016, 11:24:34 PM »
Those are all great things to examine...it may also be worthwhile looking for announcements in the media.

diablobanquisa

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Re: Northwest Passage thread
« Reply #202 on: August 01, 2016, 11:25:16 PM »
Those maps from the Canadian Ice Service would be more detailed, but I'm not sure if there's an archive.

Yes, they have a nice archive: http://iceweb1.cis.ec.gc.ca/Archive/?lang=en  ;)




Neven

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Re: Northwest Passage thread
« Reply #203 on: August 01, 2016, 11:45:43 PM »
Cool, thanks, Diablo!

Now to find the time to sort through all this stuff (the main reason I never looked further into this).
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Reggie

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Re: Northwest Passage thread
« Reply #204 on: August 02, 2016, 01:12:32 AM »
I have gone through the black and white weekly regional ice charts and the earliest chart with an opening of the southern route was August 27 2012

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Re: Northwest Passage thread
« Reply #205 on: August 02, 2016, 01:44:45 AM »
I have gone through the black and white weekly regional ice charts and the earliest chart with an opening of the southern route was August 27 2012

So we are in uncharted territory in a manner of speaking.  ;)

A-Team

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Re: Northwest Passage thread
« Reply #206 on: August 02, 2016, 01:51:33 AM »
Quote
maps from the Canadian Ice Service
Oh I would imagine they are just using 89V just like everyone else. There's no cloud-penetrating radar coverage by their Radarsat or Sentinel 1AB.

It's not like the CIS has someone stationed nearby making daily dogsled runs out onto the ice or doing daily plane flow-overs of the NW Passage. The cloud deck is too low and what would be the point -- conditions can change within hours.

All we know at this point is that the Northwest Passage was open on July 31st at the time of the AMSR swaths -- the bottleneck was clear by a factor of eight of their experimental resolution. Using this archive with this definition only 2013-16 could be dated which is limiting.

The advantage is the objectivity, consistency, resolution and automated processing. The latter amounts to masking, in turn, all but one of the routes and exploiting the non-dithered palette, land/sea resolution, and topologically flawless operation of the restricted color wand in detecting simply connected regions.

To expand a bit on the UH large format and why they developed it for the CAA, 2x doesn't simply mean twice the resolution or 4x the pixels. It means the binary classification of the 1x version (land or sea) becomes a hexadecimal as that one pixel becomes a 2x2 array with 2-bits at each location. That is, there are 16 ways to color that array as land or sea so for curved channels and odd-shaped islands, that's quite an improvement in the land mask and so in reliably detecting clear passages.

Yes there are satellites with far better ground resolution than this but the tradeoff is a far narrower orbital swath, far less frequent return visits, and no prospects for a composite scene assignable a single day.

Note routine cloud interference acts the other way -- to whiten the blue. Here we are seeing a huge single connected block, thin at some places, thick at others, of the zero darkest blue.

Update: On the August 1st preliminary partial release of about 3 minutes ago, the key passage has become blocked again (yellow has replaced zero blue). So it is a fluid situation in terms of floating ice. This suggests that 'records' and 'trends' in first opening will prove of limited value in tracking climate change no matter what definition is used.

ftp://ftp-projects.zmaw.de/seaice/AMSR2/3.125km/Arc_20160801_res3.125_LARGE.png (reload periodically to see the August 1st final.)
« Last Edit: August 02, 2016, 02:35:29 AM by A-Team »

Nix

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Re: Northwest Passage thread
« Reply #207 on: August 02, 2016, 05:04:52 AM »
Not all the canadian maps are upta date yet the ones that are are still Interesting

Here is the link to the Canadian ice services http://ec.gc.ca/glaces-ice/?grp=Guest&mn=&lang=en

Jim Hunt

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Re: Northwest Passage thread
« Reply #208 on: August 02, 2016, 11:13:27 AM »
There's no cloud-penetrating radar coverage by their Radarsat or Sentinel 1AB.

Not on a daily basis perhaps, but the CIS do produce their weekly Radarsat mosaics:

http://ice-glaces.ec.gc.ca/cgi-bin/getprod.pl?prodid=IPYMMR1WA

Having been through this exercise last year, I'll quote myself:

Quote
Automated passive microwave based satellite Arctic sea ice concentration products can miss ice that’s visible to the naked human eye [on MODIS].

From August 13th 2015:



Reality is merely an illusion, albeit a very persistent one - Albert Einstein

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Re: Northwest Passage thread
« Reply #209 on: August 02, 2016, 11:20:55 AM »
The approach to Bellot Strait on August 1st 2016, plus the latest UH AMSR2:

http://GreatWhiteCon.info/2016/08/is-the-northwest-passage-open-yet-2/
« Last Edit: August 02, 2016, 01:50:32 PM by Jim Hunt »
Reality is merely an illusion, albeit a very persistent one - Albert Einstein

iceman

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Re: Northwest Passage thread
« Reply #210 on: August 02, 2016, 12:44:27 PM »
    .... So it is a fluid situation in terms of floating ice. This suggests that 'records' and 'trends' in first opening will prove of limited value in tracking climate change no matter what definition is used.

Good point, though at the margin earlier dates mean more shipping via NWP and NSR, and burning bunker fuel in the Arctic is a positive feedback mechanism.

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Re: Northwest Passage thread
« Reply #211 on: August 02, 2016, 01:05:49 PM »
If we're also considering the Alaskan section of the Northwest Passage, then whilst the Barrow webcam stopped updating on July 31st it showed:



Here too is an intriguing NWS ice chart from August 1st.
Reality is merely an illusion, albeit a very persistent one - Albert Einstein

A-Team

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Re: Northwest Passage thread
« Reply #212 on: August 02, 2016, 02:43:25 PM »
Below is the 01 Aug 16 final and its analysis. According to UH AMSR2 3.1km large, the Northwest Passage is blocked now at 3 locations (X's in second frame) by pixels of non-zero sea ice concentration. The third frame (watch palette substitutions) measures how high the sea ice concentration gets in the limiting passageway: 23%.Yesterday it was all zero in this region.

The Northwest Passage, like open water at the off-center North Pole, is more of a nostalgia meme that the public might connect with, rather than a good way to monitor changes in the far North that will affect global climate.

As iceman notes, bunker fuel soot worsens albedo, hastening melt like peat fires and stove particulates, though we could question whether global commerce will continue to a significant extent as Arctic Ocean conditions deteriorate further.
« Last Edit: August 02, 2016, 02:57:09 PM by A-Team »

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Re: Northwest Passage thread
« Reply #213 on: August 02, 2016, 03:30:40 PM »
Thx to JimH for posting a new sea ice resource. The map palette is missing but recoverable; the satellite link page still awaits five minutes of staff effort. Otherwise it seems like the CIS egg page without the eggs. It is unacceptable to not provide links to the imagery on which the analysis is based.

Many earlier posts have noted the sorry state of GFS relative to ECMWF but that is nothing compared to the decline in NWS, still in all-cap typewriter font of the 1950's, parked within the Commerce Dept, and focused on serving unspecified customers-who-don't-pay.

Quote
WE ADVISE OUR CUSTOMERS TO SEEK OUT THE LATEST DAILY SEA ICE
ANALYSIS...5 DAY SEA ICE FORECAST...AND SEA ICE ADVISORY PRODUCTS
AND TOOLS ON THE NWS ALASKA SEA ICE PROGRAM WEBPAGE TO FIND THE MOST
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Check back soon! We'll update this page when some amazing satellite imagery is available.
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Rob Dekker

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Re: Northwest Passage thread
« Reply #214 on: August 03, 2016, 09:37:10 AM »
Thanks A-team and Jim on this analysis of the (not quite yet) opening of the North-West passage.
A-team notes three points where ice on the Aug 1 AMSR2 images re-appeared where on July 31 it was absent.

One of these points is in Larsen Sound, which became visible on Modis on Aug 2 due to clear skies at the time the satellite passed over :



This is a band of ice that is clearly at the end of its proverbial rope, but I agree that to have a true "open" North-West passage (as in : a ship can move through without touching ice), we need to wait a few more days.
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A-Team

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Re: Northwest Passage thread
« Reply #215 on: August 03, 2016, 03:21:34 PM »
Here's the August 2nd situation in regards to not-quite-zero sea ice concentration. Frames 3 and 4 are 3x enlargements of the large version of UH AMSR2 3k.

This cannot add any real resolution but can make 1 pixel into a 3x3 square still of the original color if 'none' is chosen as the interpolation technique.

No clear visible (or radar) imagery exists for July 31st, the day the NW Passage first fully opened according to AMSR2 3k. It is unworkable to require supporting visible imagery to the rule because this area can go many months at a time without a truly clear day over the whole Passage (or even key areas). The definition then becomes cloud-cover driven.

The same problem arises over in the Barents in trying to determine the extent of the Emiliania huxleyi bloom which could be a proxy for elevated poleward near-surface water temperatures. There has not been a single suitable day the last month, even combining terra/aqua/suomi.

On the 02 Aug 16 Modis of Larsen Sound, we've been trying to remember to include the set-up link that WorldView provides, upper right corner. This allows others to verify that the resolution was maxxed out (to just before yellow warning bars in the layer menu) and that nothing shows in bands specialized to thin clouds. http://go.nasa.gov/2aMXhHJ

What WorldView provides is quite dark so the as-is cycling through terra/aqua/suomi is followed below by non-destructive contrast normalization to fully use the brightness gamut. The snapshot feature assures that the intrinsic 250 m resolution of these instruments is not exceeded. However it has to be supplemented by a screenshot if palette squeezing has been used, as in the 4th frame below of terra, terra 367, terra 721, and terra band 31 day.

Cycling helps distinguish ice from faster moving clouds (eg upper left, Suomi only). Note there may be an algal bloom here too in shallower channels.
« Last Edit: August 03, 2016, 03:55:58 PM by A-Team »

Andreas T

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Re: Northwest Passage thread
« Reply #216 on: August 04, 2016, 12:03:28 AM »
in fewer words: visible wavelength images are showing ice which AMSR does not "see".
That doesn't make the information from passive microwave invalid or useless, it just means we can't rely on it blindly.

A-Team

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Re: Northwest Passage thread
« Reply #217 on: August 04, 2016, 12:46:12 AM »
Quote
visible wavelength images have higher ground resolution than AMSR
Right. 250 m pixels vs optimistic 3125 m. And we could purchase proprietary WoldView-3 satellite imagery for its 0.31 m resolution which is 806 times better than Modis, offering 650,000 pixels in place of that 1 aqua pixel that's bigger than 5 soccer fields butted together.

Yet a low flying CIS helicopter pilot could see snowflakes falling on ice cubes which even a small duck could brush aside even though the Northwest Passage is still not open according to a strict definition.

The advantage of AMSR is operational: open the daily product, click once with a contiguity tool set on the lowest palette bin at zero intolerance: if there is a continuous trail of pixels from Beaufort to Baffin, that route is open. Everyone gets the same outcome. A simple script can rip through every day of a multi-year archive in seconds, additionally quantifying all the open water each day in each specified scene.

That's not the case with Modis -- some people see slush, pancake and frazil; others see every speck of white as a solid floe; some see those blocking the way, others see ways to thread through them. Right now, this area would have a lot of color picking issues just due to the algal bloom. There's 38,579 distinct colors in the little Suomi image below and tomorrow's will have thousands of yet others.

Open to whom and for how long? Container ship, coal barge, cruise ship, small icebreaker, sailboat, kayak, large goose, small duck, copepods impeded by coccolithophores...

http://cms.mapmart.com/Products/SatelliteImagery/WorldView3.aspx?gclid=CKGEif-jps4CFZBbfgod0VoMKg
« Last Edit: August 04, 2016, 02:22:21 AM by A-Team »

Tealight

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Re: Northwest Passage thread
« Reply #218 on: August 04, 2016, 01:59:21 AM »
And we could purchase proprietary WoldView-3 satellite imagery for its 0.31 m resolution which is 806 times better than Modis...

Yeah and with the 700pixel restriction you can show an impressive 217x217m. Also known as nothing on the scale of the Arctic ice pack. We already struggle to show tiny glaciers like Jakobshavn at 10m resolution which really annoys me. My average monitor can display 1920x1200 pixel (4.7 times as much) and I would love to use it. Even my smartphone has Full HD and an easy to use zoom function.

I think we should choose data according to the Coastline paradox: https://en.wikipedia.org/wiki/Coastline_paradox
For the entire Arctic a resolution of several kilometers is fine. For a finding an ice free path for a cruise ship the resolution should be a few hundred meters or less.

If you have a nuclear submarine than the arctic is open all year round ;)
« Last Edit: August 04, 2016, 02:10:06 AM by Tealight »

Rob Dekker

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Re: Northwest Passage thread
« Reply #219 on: August 04, 2016, 08:15:45 AM »
Open to whom and for how long? Container ship, coal barge, cruise ship, small icebreaker, sailboat, kayak, large goose, small duck, copepods impeded by coccolithophores...

I agree. Everything is relative.
Let's sum up the facts here.
AMSR2 is really good in detecting ice, yet in this case they don't detect these swirls of ice we see on Modis. AFAIK there can be at least three reasons for that :
- ice concentration is smaller than 15 %
- ice is dominated by melting ponds
- ice is thinner than 50cm (or even worse, 20cm or so)
And of course, a combination of the three would explain the observations even better.

From A-team's close-up (250m resolution) image of this ice, it almost looks like a small 'galaxy' with some explicit dots (floes) of more than one pixel, but mostly a gray type of hue which appears to move in 'organic' ways. That suggests that the ice in Larsen Sound right now has a really small granularity. Maybe something like this (from the Healy) :



or even smaller granularity, like this :



or a combination of these two images.

Either way, for AMSR2 to miss this ice, it would have to be thin, and rather low concentration, and thus, regardless what kind of vessel may be able to pass through the North West passage right now (ship, yacht, or duck) this ice WILL clear out in the next couple of days.
« Last Edit: August 04, 2016, 08:23:54 AM by Rob Dekker »
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Andreas T

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Re: Northwest Passage thread
« Reply #220 on: August 04, 2016, 10:21:17 AM »
To illustrate why I have learned to be suspicious of AMSR ice oncentrations I am showing something which is unlikely to have much similarity with this particular area.
West of Wrangel island AMSR has shown no ice for nearly a couple of weeks (as far as I can tell without the ability to analyse the slightest differences in the darkest hues) As A-team has shown the Uni Hamburg graphic has no 15% cut off, Rob. ftp://ftp-projects.zmaw.de/seaice/AMSR2/Arc_latest_yesterday_AMSR2_3.125km.png
The visible images on worldview show, when clouds allow, some drifting chunks of ice (don't think algal blooms fit the structure even if they might lighten the background) http://go.nasa.gov/2aC7JOI
This ice is dispersed but clearly not thin or neglegible because it must be melting, surrounded by some warm water, yet has lasted this long.
Ice in this part of the NW passage can't be as thick as ice southwest of Wrangel was at the end of winter but it cautions against declarations of "WILLL".
« Last Edit: August 04, 2016, 01:49:07 PM by Andreas T »

seaice.de

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Re: Northwest Passage thread
« Reply #221 on: August 04, 2016, 01:29:41 PM »
To illustrate why I have learned to be suspicious of AMSR ice oncentrations I am showing something which is unlikely to have much similarity with this particular area.
West of Wrangel island AMSR has shown no ice for nearly a couple of weeks (as far as I can tell without the ability to analyse the slightest differences in the darkest hues) ..

AMSR2 89 GHz channels are not very sensitive to low ice concentrations. It may be that there is up to 25% ice when the alorithms shows 0%. This is still in the range of uncertainty. You could use SMOS 1.4 GHz brightness temperatures, available at http://icdc.zmaw.de/, to check for low ice concentrations. SMOS measures however only with coarse resolution but is very sensitive to ice occurrence and not very much affected by the wind roughening. Influence of water vapour is neglectiable which is not the case for AMSR2. Open water shall have values around 100K while ice may be detected with TB>110 K.

A-Team

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Re: Northwest Passage thread
« Reply #222 on: August 04, 2016, 05:17:34 PM »
AMSR rain layer?

The animation just shows a wild goose chase within the extended feature set of WorldView for August 3rd in the Northwest Passage. I set off in search of capture of the snapshot tool boundary which is necessary to replicate our set-up for others at the forum.

The lat/lon displays ok outside snapshot corners but is not to be found in the full length url capture tool which instead (v=etc) shows the corners of the overall tab window, possibly in some version of mercator coordinates (though seemingly not explained at info links).

August 3rd was notably cloud free. It may be better not to use the land mask because white that is ambiguous over sea has to be clouds when it extends over snow-free land. The algae bloom throws off any effort to set a fiducial color for open water and so complicates any segmentation scheme.

Maybe after melt season is over, there will be time to read the WV manual?
« Last Edit: August 04, 2016, 05:38:11 PM by A-Team »

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Re: Northwest Passage thread
« Reply #223 on: August 04, 2016, 06:23:33 PM »
Here is the NW Passage from 2015 within the context of what the Arctic Ocean was doing (according to UHH AMSR2 3k). The date range is 03 Aug to 15 Sept (with some dates omitted because of bad mask glitches and blank files at the archive, making me think I'm the only person who has ever used it!).

I'll add 2013 and 2014 to this post as time permits. To get at 2016 -- which obviously hasn't happened yet so isn't in the archive -- the 'melting momentum' technique described earlier (where blueish color bins are pushed up the palette) can be balanced by increasing 'freeze-up momentum' (whitish color bins are pushed down the palette).

Applying this method to 2013-15 (which have known outcomes), confidence in the 2016 prediction can be assessed. The freeze-up of 2015 can be seen clearly towards the end of the animation below as the intermediate concentration blues whiten up.

It's advantageous to gang up animations in gimp to 2x2 and higher arrays, the advantage being different years or different regions are forced to display in synch. These could be done at most as 4900 x 2800 pixels = (700x7) x 700x4) = 7x4 forum array (displayable on the large AAPL monitor) and only reduced to forum size at the end. The full size view might not animate at the speed that it is set for depending on the graphics card and cores but would still be advantageous for scientists trying to see all the data at once at source resolution.

The easiest way to multiplex animations in gimp is to first make the individual animations. Then for the first row of the big animation, rotate CCW by 90º and abut each with 'filmstrip' into a long column. Then save and import into the first columnated filmstrip as layers. Set the preferred final order and re-filmstrip. Repeat with the second, third ... rows of animations. Then use Image --> Guides --> Grid to set final animation frame boundaries and Filters --> Web --> Slice which saves the individual ganged frames into numbered files. Open the first and import the others as layers.
Set the pause on the long frame and let the others default.

In the example here, the width was taken as 349 which works out to 698 for the 1x2 shown which allows for a 2 pixel vertical separator at 700 pixel forum width. The color set as background will fill the gap if the alpha channel is removed. Otherwise forum background blueish grays will fill in, the darker for odd numbered posts relative to the top of page.
« Last Edit: August 05, 2016, 12:56:21 AM by A-Team »

Andreas T

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Re: Northwest Passage thread
« Reply #224 on: August 04, 2016, 09:07:16 PM »
Thank you seaice.de! Good to have some input from someone with more background in the data sources.

A-Team

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Re: Northwest Passage thread
« Reply #225 on: August 05, 2016, 02:15:24 AM »
Yes, great to have informed technical input.

However like Defense Minister Rumsfeld said, in rationalizing cheap troop vehicles with no protection against road explosives, "you have to go to war with what you've got". In our case that is UHH AMSR2 3.1k as there does not seem to be a better open source alternative multi-year whole Arctic Ocean cloud-penetrating archive online.

If there is, just post the link to the ftp archive and DOI's of supporting publications, sparing us excuses concerning task difficulty, UHH critiques and the image collections of dithered postage stamps in unspecified projections.

In any case, scripts have to be developed, they can run anywhere. While UHH sea ice concentration bin occupancies may not be spot-on, they provide adequate proxies for establishing closed operations on palette cross products. These are essential to analysis as it scarcely seems workable to perform topological procedures on netCDF numeric arrays.

For now, we have something a lot better for seeing through clouds than Modis, Landsat or S2AB. We've verified many times in cloud-free patches that UHH does an excellent job on sea ice edge, that it's often consistent with S1A in coverage patches, and that ground resolution is quite satisfactory in terms of rotation, displacement and splitting at the level of individual floes.

Here is the 2013 animation, at 7.3 MB not too large for the forum given a fast uploading connection. It runs from August 1st to September 25th. The dates are not embedded but available as the frame names if you download the gif. It is slightly compressed to retain the whole Arctic Ocean context.

Downloading the component files is very convenient as the UHH archive server allows anonymous ftp (user and password) and offers better image selection than the web page. I use Mac freeware called Fetch as ftp client.

Be careful what you ask for though or you could end up with a half hour download of Antarctica netCDF files by mistake. The one technical annoyance in UHH mage format is a 'png offset' that serves no purpose and is handled poorly by gimp.
« Last Edit: August 05, 2016, 02:22:56 AM by A-Team »

ghoti

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Re: Northwest Passage thread
« Reply #226 on: August 07, 2016, 01:53:34 AM »
I've been looking for info on small boats attempting the 2016 Northwest passage without finding much. I normally rely on http://www.thenorthwestpassage.info/ site but it still is showing 2015.

https://toptotop.org/2016/08/05/expedition-report-bering-sea-wild-winds-snow-ww2-ruins/  is the only boat I've seen heading for the passage so far.

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Re: Northwest Passage thread
« Reply #227 on: August 07, 2016, 05:47:35 AM »
ghoti - you may be a bit early. At http://arcticnorthwestpassage.blogspot.com/2016/08/20160801-northwest-passage-roll-call.html there is a list of boats from small (9m long Yvinec from France, temporarily impounded at Pond Inlet for firearm possession) to large (250 m long Crystal Serenity, in Sitka, Alaska and due to leave Seward on 8/16 for the Northwest Passage) that were planning, as of August 1, to attempt the Northwest Passage this year. The same website has articles about individual boats, including the Yvinec's encounter with Canadian customs at Pond inlet.

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Re: Northwest Passage thread
« Reply #228 on: August 08, 2016, 01:44:45 AM »
I'll copy in the post with all the other years when 2016 opens. For the sake of consistency I'm using the same methodology I used with all the other years. As of the 7th August the southern NW route is still not open.

In particular there is still a small amount of rubble in the Peel sound. Larson sound also has alot of ice still in it although there may be a route through it; its not always easy to tell with the cloud. It was unambiguously completely closed on the 3rd though - the last time we had completely clear skies.




Rob Dekker

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Re: Northwest Passage thread
« Reply #229 on: August 10, 2016, 09:00:56 AM »
The "Home brew AMSR2 extent & area calculation" thread had two important posts about the North-West passage which are worth repeating :

This animation from Wipneus :



which shows that Larsen sound dropped off the AMSR2 radar since July 31, suggesting the NW passage is open since that time, and this post from seaice.de



which shows that even now Larsen sound still has a small band of low concentration ice that AMSR2 missed.

If the NW passage is open or not at this time depends on your definition of "open".
« Last Edit: August 10, 2016, 09:23:43 AM by Rob Dekker »
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Andreas T

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Re: Northwest Passage thread
« Reply #230 on: August 10, 2016, 09:49:14 AM »
Thanks for bringing these images over here, Rob, its good to have this information in one place. To be fair to AMSR2 the Uni Hamburg chart has a little more ice which gets lost in Wipneus' animations where the contrast is enhanced. But I think it is now well established that if those low concentrations matter, information has to come from other sources.

ghoti

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Re: Northwest Passage thread
« Reply #231 on: August 10, 2016, 03:01:25 PM »
If I recall correctly a group of small boats which included S/V Salty Kisses completed the section between Bellot Straight and Cambridge Bay when the CIS maps showed 7/10 ice. Videos posted by Salty Kisses after the boat was safely in southern Alaska showed the 3 boats slowly moving through water that looked more like 9/10 ice with a person on the bow of each boat pushing blocks of ice out of the way with a pole.

There is currently much less ice visible in the passage now than when they sailed through last year.

RoxTheGeologist

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Re: Northwest Passage thread
« Reply #232 on: August 11, 2016, 01:09:08 AM »
Hey, I know it's not the standard route, but would if be possible to use the Foxe Basin, Fury and Hecla Strait into the Gulf of Boothia, and then travel through the Bellot Strait to meet up with the 'southern' route for the northwest passage?

From what I have read the two narrow straits are usually iced up, but this year the warmth in the CAA is such that they may become ice free.
« Last Edit: August 11, 2016, 01:21:24 AM by RoxTheGeologist »

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Re: Northwest Passage thread
« Reply #233 on: August 11, 2016, 01:57:41 AM »
Adding 2016 to the post I did. Again its not perfect but I'm using the same methods I used for the other years to keep consistency. I'm saying the southern part of the NW route opened on the 9th August (see attachment).

Just for reference, the dates that the NW passage (southern and northern routes) and the northern route open for the last few years. I always think this is an interesting bit of information.

Reference for the NW passage routes above. Note in some cases the routes may close again, these are the approx dates they first opened.

2012
Southern NW route: August 9th
Middle NW route: July 31st
Northern NW route: August 27th
Northern route: August 4th

2013
Southern NW route: August 22nd
Middle NW route: Does not open
Northern NW route: Does not open
Northern route: August 29th

2014
Southern NW route: August 30th
Middle NW route: Questionably around September 14th
Northern NW route: Does not open
Northern route: August 7th

2015
Southern NW route: August 13th (taking a ridiculous maze like path around the ice though)
Middle NW route: September 8th
Northern NW route: September 8th
Northern route: July 31st

2016
Southern NW route: August 9th
Middle NW route: -
Northern NW route: -
Northern route: -

So it opened on the same day as 2012 (although in 2012 the middle route had also opened remarkably by the 31st July), 4 days earlier than in 2015 and several weeks in advance of the other years. Its worth noting however at this point 3/4 of the examined routes in 2012 were open compared to just 1/4 so far in 2016, 2015, 2014 with only 2013 having all routes still closed at this point.

So in so far as the NW passage and N route in general goes; definitely less easy than 2012; definitely easier than 2013 and perhaps not yet clearly distinguishable from the other post '12 years. 

ghoti

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Re: Northwest Passage thread
« Reply #234 on: August 11, 2016, 03:03:56 AM »
Hey, I know it's not the standard route, but would if be possible to use the Foxe Basin, Fury and Hecla Strait into the Gulf of Boothia, and then travel through the Bellot Strait to meet up with the 'southern' route for the northwest passage?

I think that's know as route 7.

https://1.bp.blogspot.com/-96EVgV2xPwk/V6icnwIUVuI/AAAAAAAA5T0/XuxcyP_k0PAUgXtYje4O_XmrR8l-99UPACEw/s1600/NWP_Routes-6.gif

RoxTheGeologist

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Re: Northwest Passage thread
« Reply #235 on: August 11, 2016, 05:37:35 AM »
Hey, I know it's not the standard route, but would if be possible to use the Foxe Basin, Fury and Hecla Strait into the Gulf of Boothia, and then travel through the Bellot Strait to meet up with the 'southern' route for the northwest passage?

I think that's know as route 7.

https://1.bp.blogspot.com/-96EVgV2xPwk/V6icnwIUVuI/AAAAAAAA5T0/XuxcyP_k0PAUgXtYje4O_XmrR8l-99UPACEw/s1600/NWP_Routes-6.gif

Thanks! Yes that's the one!

Jim Hunt

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Re: Northwest Passage thread
« Reply #236 on: August 17, 2016, 10:10:00 AM »
Hey, I know it's not the standard route, but would if be possible to use the Foxe Basin, Fury and Hecla Strait into the Gulf of Boothia, and then travel through the Bellot Strait to meet up with the 'southern' route for the northwest passage?

In a word. Yes. See the definitive reference on such matters:

www.americanpolar.org/wp-content/uploads/2015/11/NWP-2015.pdf

which mentions:

Quote
1975
14 Pandora II1 (hydrographic research vessel)
15 Theta (research vessel)
Travelled in company

2006
109 Kapitan Khlebnikov (icebreaker)


Reality is merely an illusion, albeit a very persistent one - Albert Einstein

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Re: Northwest Passage thread
« Reply #237 on: August 21, 2016, 01:17:45 AM »
Article at today's Huffpost  (http://www.huffingtonpost.com/entry/crystal-serenity-cruise-northwest-passage-arctic_us_57b75397e4b00d9c3a17902b?) about cruise ship just beginning a NW Passage attempt. Only near Nome, AK at moment but bow, starboard, and aft on-board streaming cameras might be worth a look once it gets into the passage.

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Re: Northwest Passage thread
« Reply #238 on: August 21, 2016, 01:30:03 AM »
Article at today's Huffpost

Dare I mention my own musings on the self same topic?

http://GreatWhiteCon.info/2016/08/crystal-serenity-sets-sail-for-the-northwest-passage/

Quote
Listen to what Admiral Charles Michel, Vice Commandant of the United States Coast Guard, had to say in testimony before the House Subcommittee on Coast Guard and Maritime Transportation in answer to questions from Congresswoman Janice Hahn.
Reality is merely an illusion, albeit a very persistent one - Albert Einstein

APMartie2

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Re: Northwest Passage thread
« Reply #239 on: August 21, 2016, 02:58:00 AM »
: Jim Hunt  Today at 01:30:03 AM

Dare I mention my own musings on the self same topic?
http://GreatWhiteCon.info/2016/08/crystal-serenity-sets-sail-for-the-northwest-passage/
------------------------------------------------------------------------------------------------------
Yes, please! Should have checked Great White Con before posting. I added your site to my bookmarks bar and will check daily as a budding Arctic Ice enthusiast. Thanks.

I am to Wayne and Garth as you are to Aerosmith!  :)


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Re: Northwest Passage thread
« Reply #240 on: August 21, 2016, 09:02:57 AM »
Which would seem to be explained by this AMSR2 image from last September. Perhaps there should be a poll Neven?!
I think this still looks particularly interesting and relevant to todays discussion!

 :o
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Re: Northwest Passage thread
« Reply #241 on: August 21, 2016, 11:58:37 AM »
Article at today's Huffpost  (http://www.huffingtonpost.com/entry/crystal-serenity-cruise-northwest-passage-arctic_us_57b75397e4b00d9c3a17902b?) about cruise ship just beginning a NW Passage attempt. Only near Nome, AK at moment but bow, starboard, and aft on-board streaming cameras might be worth a look once it gets into the passage.

Welcome to the ASIF!  :)

Because this thread is focused on the science, a few months ago I started a dedicated thread for more general discussion about the voyage of the Crystal Serenity over in the "Consequences" section.

I thought it might be a good idea to keep a running record, as it were, of the CS voyage in real time in a separate space where the implications of this voyage (and others like it) may be addressed. Check out the thread "Cruising the Northwest Passage, anyone?" here:

 http://forum.arctic-sea-ice.net/index.php/topic,1514.0.html

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Re: Northwest Passage thread
« Reply #242 on: August 21, 2016, 12:54:10 PM »
I think this still looks particularly interesting and relevant to todays discussion!

In which case here is the 2015 equivalent:
Reality is merely an illusion, albeit a very persistent one - Albert Einstein

Jim Hunt

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Re: Northwest Passage thread
« Reply #243 on: August 21, 2016, 12:57:59 PM »
I am to Wayne and Garth as you are to Aerosmith!  :)

You are very kind. In actual fact I suddenly find myself a big fan of Hayseed Dixie!

https://twitter.com/jim_hunt/status/758692973408292864
Reality is merely an illusion, albeit a very persistent one - Albert Einstein

abbottisgone

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Re: Northwest Passage thread
« Reply #244 on: August 22, 2016, 08:55:36 AM »
I think this still looks particularly interesting and relevant to todays discussion!

In which case here is the 2015 equivalent:

Really, I suppose it all comes down to the weather  ;D
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Re: Northwest Passage thread
« Reply #245 on: August 26, 2016, 02:18:31 PM »
Lucky for the CS that it can take the southern "shallow draft" route of the NWP. See in this Ice Chart how persistent westerly winds have now pushed the Polar Pack into McClure Strait closing it to normal ship traffic, as well as closing the entrance to POW strait. Should deter anyone thinking of regular deep-draft traffic...

Jim Hunt

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Northabout braves the Northwest Passage
« Reply #246 on: August 27, 2016, 04:45:23 PM »
The Polar Ocean Challenge team in their yacht Northabout have completed the first half of their polar circumnavigation by officially completing the Northern Sea Route:

http://GreatWhiteCon.info/2016/08/northabout-races-for-the-date-line/#Aug-27

After a couple of days R&R in Barrow they''ll be setting off through the Northwest Passage. The current route plan goes via Bellot Strait, but it looks like a variety of other possibilities are available:

Reality is merely an illusion, albeit a very persistent one - Albert Einstein

Jim Hunt

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Re: Northwest Passage thread
« Reply #247 on: August 29, 2016, 11:12:22 AM »
Hey, I know it's not the standard route, but would if be possible to use the Foxe Basin, Fury and Hecla Strait into the Gulf of Boothia, and then travel through the Bellot Strait to meet up with the 'southern' route for the northwest passage?

The answer is definitely YES! David Scott Cowper in Polar Bound has just traversed that route in a westerly direction for the first time, since modern records began at least:

http://GreatWhiteCon.info/2016/08/david-scott-cowper-makes-history-again/
Reality is merely an illusion, albeit a very persistent one - Albert Einstein

Andreas T

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Re: Northwest Passage thread
« Reply #248 on: August 29, 2016, 11:42:40 AM »
Do you expect Northabout to be visible on the Barrow webcam when the daily footage updates to the 28th? according to the track it has sailed past the spit of land east of Barrow and is now in the lagoon behind it. I know the camera does not point to where Northabout is now but could it have been seen as it was moving along the coast (I have no idea how far out it could be seen)

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Re: Northwest Passage thread
« Reply #249 on: August 29, 2016, 03:08:06 PM »
Do you expect Northabout to be visible on the Barrow webcam when the daily footage updates to the 28th?

I did look at the webcam images, but saw no sign of Northabout. They passed the webcam several km offshore though:

http://GreatWhiteCon.info/2016/08/northabout-races-for-the-date-line/#Aug-29
Reality is merely an illusion, albeit a very persistent one - Albert Einstein