95% of the population lives within 20 feet of sea level and they won't move? The population will crash that much well before the ocean level rises that much anyway. Of course you have the usual idiot denialists of AGW, and overpopulation, for that matter.
Being well on course toward a 6*C temperature rise unless drastic measures are taken VERY quickly, it is assured that the tipping point of tundra methane self release we were reported AT in 2009, will be well passed and nothing will stop a similar event, quicker by far, than the thermal maximum of approximately 55 million years ago. If it gets that far from lack of doing anything, then most species will go extinct. With something so threatening, you would think that discretion would be to reduce emissions the 90% recommended by 2020. Then you have the greed of corporate fossil fuel sellers and users, and their minions, the snow eater denialists, preventing enough change in time.
Denialists tend to disregard the sensitivity of tundra methane release, or look at the sensitivity to minor warming for oceanic methane hydrate deposits, which tend toward explosive release at +1*C or by mechanical action like attempted mining or seismic events.
Of course, the methane turns to CO2 and water vapor after 15 years, with the CO2 continuing the heat trapping effect to a lesser extent and the water vapor with a slight positive heat trapping effect.
There are those who think we will be OK with a 50% drop in CO2 emissions from 1990 levels by 2050 (when the population will be crashing or close to it). They think it will hold AGW to 2*C, and also disregard the sensitivity of the tundra methane tipping point, and the heat increase concentrating at the north polar regions more than anywhere else (although the increase will have profound effects on the Antarctic, too).
Canada may benefit temporarily, with a greater growing area and longer growing season, but, personally, I think all denialists should be rounded up and sent to "disintegration booths".