The official line (by the scientists directly involved in the research) is that global warming is real and it may be in part caused by humans. I think the jury is still out on global warming, but I think it's a bit blithe to assume this is just junk science. It won't be like that movie, but you'd hate for the drought out west to be permanent. (That's the kind of thing that climate change could cause.) This is why I'm a big fan of nuclear power.
Easy for you to say, but in 300,000 years some mentally defective person might dig up the waste and eat it. Are you prepared to run that risk?
To even think that humans can have any lasting impact on the earth is the height of vanity. The earth was here before us, and the earth will be here after us. Humans are only a blip on the screen. Human capability for abstract thought does not change the fact that humans are weak, soft, temporary skin bags of protoplasm that will die and decay.
Droughts go with Ice Age temperatures -- the water vapor in the air is reduced by being locked up as ice.