I am just apathetic. But I do think about people who have kids that have a bery bleak outlook. I don't feel anything but I'm sure if I did I'd be angry for them. I don't see any point in thinking about it much anymore when we have countries that have no regulations and the US trying to deregulate everything. Whatever... short sightedness and greed.
I cope with it by activism. Doesn't have to be something related to global warming, just anything, it makes you feel able to change world a little. Also, by working in a volunteer labor, you concentrate on presence and not waste your thoughts on things you have no power over.