You know, that's actually a really creepy mental image: the entire globe painted in lurid colors of latex paint. All food sources are coated and inedible. Every plant is coated and photosynthesis fails. Amphibians can't breath through their skin and die. People can't sweat and die of heat exhaustion. The entire biosphere is cut off from the sun and dies and rots under a millimeter-thick coating of bright paint. Anerobic bacteria gorge themselves, releasing gases that bubble the paint. Earth is left looking like a psychedelic beach ball with blisters. Somewhere in the deep sea, only the tube worms that live off deep ocean volcanic vents are left to carry life forward.