[az_gila]

Update - two simpler links.

To the cruise ship Serenity -

http://www.sailwx.info/shiptrack/shipposition.phtml?call=C6SY3

And to the Ernest Shackleton, the supply ship/icebreaker mentioned in the article which seems to be heading from the East to meet the Serenity.

http://www.sailwx.info/shiptrack/shipposition.phtml?call=ZDLS1

[Enchante]

Looking at NASA imagery, it seems like they run a pretty significant risk that ice could be pushed down from the north in a big storm. They have a window to make it through but it's far from guaranteed. [Not that I claim to know anything about traveling through the Arctic....]

A Nearly Ice-Free Northwest Passage August 20, 2016

"What’s left of the ice in 2016 is opening up fast. Meier expects that the Northwest Passage will open up completely in the next couple of weeks. Moreover, a strong Arctic cyclone appears to be approaching the archipelago. It could push the ice around and further open up still-blocked channels. Or, it could have the opposite effect and push in ice from the north."