Author Topic: Ice Hunters - Progress  (Read 468 times)

Kevin

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Ice Hunters - Progress
« on: October 16, 2017, 10:29:48 pm »
Here is an update on the current progress getting ship ice observations translated into data, which is actually a series of iterations starting with identification of target (ice obs containing) logbooks and transcription of positions and navigation information written therein. From this stage Michael reconstructs the ship's best possible track using piloting (bearings and ranges) and DR (course and speed) information and adds any additional sea ice notation found in the logs. So far we have ice voyage tracks for: BEAR (1900-1903, 1905, 1908-1919, 1921-1926), THETIS (1902-1904, 1906-1908), and NORTHLAND (in progress). Something close to 15,000 ice obs I would estimate. The page-level URLs are also added to every line at this stage so a) its easy to refer to the log page in editing, and b) so future researchers can also easily access the specific primary material. 

When I receive the re-navigated files I add a simple ice index to every hour where there is relevant information noted in the log - that is, where the log may say 'worked through field ice for the entire watch, half speed' I enter an index value of 1 (equals 'ice present'; 0 = none) for all hours. Then I enter the operative terms for both the ice and the ship's movement. These could be 'field' for ice, and 'worked; half' to capture the key information in the entry. When all of the logs are indexed, then we will evaluate the content of the vocabulary used in some semi-quantitative way that can be plotted on a map. So far I'm finding the vocabulary limited to a few terms, the most popular being 'field'. About half of the BEAR logs are at this stage now.





AvastMH

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Re: Ice Hunters - Progress
« Reply #1 on: October 17, 2017, 06:45:55 pm »
That's very interesting Kevin. Sounds like a lot of details are all ready forming. That's heartening  :)

Randi

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Re: Ice Hunters - Progress
« Reply #2 on: October 19, 2017, 01:24:51 am »
Keep an eye on this topic.

We hope that via Bob's spreadsheet transcribing system the OW transcribers will soon be supplying the data to Michael !

AvastMH

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Re: Ice Hunters - Progress
« Reply #3 on: October 19, 2017, 11:18:40 pm »
Keep an eye on this topic.

We hope that via Bob's spreadsheet transcribing system the OW transcribers will soon be supplying the data to Michael !


Yeh!!!  :D :D :D

Kevin

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Re: Ice Hunters - Progress
« Reply #4 on: October 20, 2017, 09:19:36 pm »
An observation from 1919.

​11 Aug. 1919, ​70.3 N, 163.0 W

Ascertained that by reason of the southern limit of the pack being in the vicinity of Lat. 70 deg. N, and the continual drift of the pack to the southward since August 7, that the set of the current has been to the southward, entirely counteracting the constant northerly current setting along the Alaska shore. It is thought that this is the extreme limit the pack has ever reached, that the southward set of the pack has been entirely due to continual northerly winds blowing for a long period of time.

​12 Aug. 1919, 70.44 N, 162.6​ W

The continual S.W. and South winds have banked ice up along the Alaskan shore, and made an impenetrable barrier north of Latitude 70 deg. 20' N, Longitude 163 deg. 00' W. On account of the leaky condition of the boiler it is not deemed expedient to stand to the northward and westward for a clear passage, because of the liability of strong east winds moving the pack off shore, thereby imprisoning the vessel and making extrication impossible.

Bourke and Paquette found a similar situation of the ice during the MIZPAC 1975 cruise in the USCG icebreaker GLACIER. It will be interesting to compare with the rest of the new data we're generating...

AvastMH

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Re: Ice Hunters - Progress
« Reply #5 on: October 20, 2017, 09:36:14 pm »
It's an amazing feeling - putting the Arctic ice on the map. Strangely it didn't feature on the Voluntary Service section of the careers booklet I got at school  ;) :D

mapurves

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Re: Ice Hunters - Progress
« Reply #6 on: October 20, 2017, 11:21:24 pm »
It's an amazing feeling - putting the Arctic ice on the map. Strangely it didn't feature on the Voluntary Service section of the careers booklet I got at school  ;) :D

Our guidance counselor, when I was in Grade Seven, may have mentioned, but I might have been asleep at the time.  ;D ;D ;D

AvastMH

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Re: Ice Hunters - Progress
« Reply #7 on: October 20, 2017, 11:28:15 pm »
It's an amazing feeling - putting the Arctic ice on the map. Strangely it didn't feature on the Voluntary Service section of the careers booklet I got at school  ;) :D

Our guidance counselor, when I was in Grade Seven, may have mentioned, but I might have been asleep at the time.  ;D ;D ;D

You need a lot of sleep at that age  ;) ;) ;D

Randi

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Re: Ice Hunters - Progress
« Reply #8 on: October 20, 2017, 11:52:13 pm »



mapurves

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Re: Ice Hunters - Progress
« Reply #9 on: October 21, 2017, 12:13:54 am »
Here's what the Northland voyage for 1933 up until the end of August looks like.



The ice areas are notable by the hourly positions. For days with no ice, just the noon positions are given.

Randi

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Re: Ice Hunters - Progress
« Reply #10 on: October 21, 2017, 12:35:53 am »
 8)

AvastMH

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Re: Ice Hunters - Progress
« Reply #11 on: October 21, 2017, 12:51:39 pm »
That's impressive Michael  8) 8)

Kevin

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Re: Ice Hunters - Progress
« Reply #12 on: December 07, 2017, 03:10:19 am »
Ice model comparison using a sample of Burton Island 1955 thickness data found in Hydrographic Office Technical Report 46. The ship positions are color coded to the model scale, so the closer the color the better the result.

Thickness https://gfycat.com/gifs/detail/SophisticatedEllipticalAmericantoad
Concentration https://gfycat.com/gifs/detail/GlaringUncomfortableHyena
 
The model is the newly created PIOMAS-20C sea ice reanalysis, in turn forced by the ERA-20C reanalysis, and covers 1901-2010. There may be some cross-talk between the concentration result and forcing data set in ERA-20C, but the thickness is not affected.

Here is Bear 1901 and 1914 as well, but just showing ice present or not in the logbook at this stage:

https://gfycat.com/gifs/detail/MedicalQueasyIrrawaddydolphin
https://gfycat.com/gifs/detail/OblongWarpedBuzzard

We're pretty excited with these results.