@MikeM Thanks for reaching out, that sounds like an amazing trip!
While we aren't quite as far north as Svalbard Island, up here in Fairbanks, Alaska we are accustomed to coping with extreme arctic temperatures. The name of the game for me is layering. Our winters can range in temperatures from 40 degrees below zero to above freezing, and the best way to handle those variations is the ability to adapt your clothing and outerwear system. I recommend a good base layer to start, my favorite is merino wool but synthetic works well too. Then a mid layer, which could be a heavier weight shirt or a light insulated jacket, followed by an outer layer, which may be insulated if you're facing extreme cold temperatures. Since you're going on a cruise and you'll be exposed to elements on the water, I imagine it would be important for your outer layer to be waterproof and breathable. Here is an Expert Advice article that goes into more depth about layering.
If you're worried about being cold, one of the most important features of a jacket when fighting off the cold is the ability to seal the openings. Look for a draw cord around the hem/waist, velcro cinch closures on the wrists, and, for insulated jackets, a baffle around the neck. Since you're traveling in summer you probably won't face too extreme of cold, however it all really does depend on what you're used to and how you acclimate to a new temperatures.
I hope this helps, please let us know if you have any other questions. Enjoy your trip!
Hi @MikeM .
I'm not an REI employee. I don't live in, nor have I traveled in any extremely cold locations. Here in the Mid-Atlantic, single digits is about as cold as it usually gets. @REI-JohnJ is probably your best resource for overall clothing options, but I can tell you that, in my case, if my feet get cold, then I'm cold. Don't forget to consider the shoes and socks you'll be wearing; and also good gloves and a hat. They'll go a long way in working with your base layers and outerwear to help keep you warm and comfortable.