Mercy of the Elements
Ships are not the easiest things to keep temperature regulated. When Yamato was completed with air conditioning in 1941, it was considered a major luxury. You can find a lot of pictures of ships in the tropics with awnings spread over their main decks, to provide shade for the crews. Particularly during the day, belowdecks would become stifling as the sun heated the ship. In the polar regions, the opposite problem occurred, as the cold climate sapped heat from the hull, and ice buildup would further sap the heat, besides the ensuing structural problems. Modern ships are better equipped to handle extreme climates, but proper crew gear is as important as always.