Alex Bailey / Twentieth Century Fox
Eco-disaster: Dimming sun
Solution: Launch a spaceship armed with a massive nuclear weapon to detonate on the sun, hopefully re-igniting that big ball of gas. Also hope that the crew doesn't pick up a crazy astronaut or that they won't go crazy themselves during the journey. It should be noted that despite the presence of "28 Days Later" director Danny Boyle at the helm, no zombie-vampires make an appearance.