See the Woods Hole Oceanograhic Institute website
http://www.whoi.edu/home/
See the articles on thermohaline circulation system and abrupt climate change regarding the potential for abrupt transition into an ice age and indications that it isn't global warming that we face.

Also consider that for millions of years the climate of the earth has been characterized by "ice ages" on the order of 100,000 years duration alternating with "interglacial periods" on the order of 10,000 years duration.

Also consider that the present interglacial period is about 12,800 years long and that this is reported to be equal to the length of the longest interglacial period as determined by fossil ice records, etc.

Don't bet the farm on a move to Canada based on reports of global warming which seem to have large political components and elements of hysteria.