Charting the Nortwest Passage

[phiggins]

Noticed a few threads lately talking about the North West Passage and wondered how does one know when the passage is free enough of ice to transit?

Thought this would be a good job for the new Landsat feature of GE2KAP. It creates charts from the Landsat 8 satellite which images the entire earth every 16 days.

First I used GE2KAP to create a chart of Google earth for part of the NWP, images from it were from taken in 2013. Then I downloaded the Landsat images near the entrance to the NWP which were acquired yesterday by Landat and used the GE2KAP Landsat_chart program to create some charts.

The first attachment is the GE chart and shows the outline of the Landsat charts. I put waypoints on the land so I knew where it was in the Landsat charts,

The second attachment is the first Landsat chart showing the channel created from the natural colors bands 432. The second is the one I enhanced the image using the Atmospheric Penetration Infrared Bands 765.

I know the icebergs won't be in the same place in a short time but at least it gives you an idea when the NWP is clear enough for a passage.

[Dockhead]

Very interesting and probably very useful, but primary tool should be the official ice reports. You cannot navigate those waters without serious passage planning, and the thing to start with is the ice reports.

https://www.ec.gc.ca/glaces-ice/

[phiggins]

Thanks,. I wonder how they get their data.

[jackdale]

You might try

https://www.arcus.org/sipn/sea-ice-outlook

For forecasts

Sent from my SM-T705W using Cruisers Sailing Forum mobile app

[wrwakefield]

Hi Paul,

That could prove useful for adding snapshots of details missing in the macro level information we use here in Alaska. [e.g., See Alaska/Arctic Analysis]

Thank you for all of your very qualified contributions- making things better for us all.

Cheers!

Bill

[jheldatksuedu]

I also thank you fro this interesting info, in the future I may attempt a passage.

[phiggins]

Thanks Bill.

Did some more work on this and ported some programs written by Dan Stahlke from the Geographic Information Network of Alaska that pansharpens the Landsat 8 image.

Attached are two screenshots of an area in northern Alberta which had some devastating forest fires last month. The first is using the 754 Landsat 8 bands and the second is the same image pansharpened using the Panchromatic band 8. You can see the fires much clearer in the second.

[wrwakefield]

Originally Posted by phiggins

Thanks Bill.

Did some more work on this and ported some programs written by Dan Stahlke from the Geographic Information Network of Alaska that pansharpens the Landsat 8 image.

Attached are two screenshots of an area in northern Alberta which had some devastating forest fires last month. The first is using the 754 Landsat 8 bands and the second is the same image pansharpened using the Panchromatic band 8. You can see the fires much clearer in the second.

Paul, you are right, the differences are striking.

Very useful to know.

Cheers!

Bill