FILE - In this Aug. 21, 2016, file photo people prepare to take a polar plunge in the Bering Sea in front of the luxury cruise ship Crystal Serenity, which anchored just outside Nome, Alaska. The ship... more 
FILE - In this Aug. 21, 2016, file photo people prepare to take a polar plunge in the Bering Sea in front of the luxury cruise ship Crystal Serenity, which anchored just outside Nome, Alaska. The ship made a port call as it became the largest cruise ship to ever go through the Northwest Passage, en route to New York City. An increasing demand for Alaska cruises is prompting some cruise lines to add more and larger vessels to their Far North lineups for the 2017 tourist season. (AP Photo/Mark Thiessen, File) less 
1 / 30
Associated Press | Photo By Mark Thiessen, File
Fri, Sep 30, 2016 3:51 PM EDT