What is the biggest threat facing our Canada in the next 50 years?

I believe that the issue of global water supply will affect Canada in the near future. With the great lakes combined with the northern glaciers Canada has one of the biggest deposits of fresh water. As mentioned in a lot of class discussions people don`t feel the gravity of an issue until it affects them directly.  I believe that if we don`t find a way to supply other countries with water, everyone will turn to Canada and it will affect Canadians directly. The government may have to limit the water supply or raise prices or worst case scenario and highly unlikely: someone invades. All three scenarios will cause serious problems to Canada`s economy (some more than other) but there are possible solutions. It has been predicted that Canada Northern climate will get warmer and with the increase in population it may provide attractive living conditions. And perhaps with the people and climate we can extract glacier water much easier. It is long shot must make their will be enough water to go around. Perhaps global warming and the changing of the Earth’s climate may create new fresh water opportunities elsewhere. A more common belief is that we find a new method of extracting fresh water from the sea. Currently our methods are too expensive and ineffective and the natural water cycle is too long and does it work in such a way to supply our demand. In African desserts they learned how to extract water at night from the methods an indigenous beetle. I think what we should take from that is Nature still has a thing or two to teach us and perhaps we are not looking close enough.