As part of Canada reasserting their rights over the Northwest Passage, the Canadian Navy has sent the HMCS Montreal to the Arctic this year. Last year the HMCS Fredicton was there.
Hopefully the Navy will not discover the hard way why Arctic icebreakers have special steel hulls with an ice belt of 3" thick steel and reduced scantlings.
Even with Global warming and reduced ice thickness, somehow the thought of taking those lightly built hulls north makes me cringe. I would suspect that the engineroom cooling systems have no recirculation features built in for slush conditions and the crew are more familar with keeping their engines running cool in the tropics then warm in the far north.
A recent article in the Halifax NS news highlights their difficulties:
http://www.herald.ns.ca/Canada/523691.html
As marine engineer who has not been to the Arctic since the early 90's, the sight of all the open water is astounding.