Here’s proof that the world can solve environmental crises: The once gaping hole in the Ozone layer is well on its way to making a full recovery, according to a new study. The ozone hole used to be the biggest problem facing the whole planet. Without the ozone’s protection, the sun’s ultraviolet light was going to burn us all. An environmental summit in 1987 called for the abolishment of the chemical materials, used in refrigerators, air conditioners, and even hair spray, that were particularly harmful to the ozone layer. Since then the ozone hole has been steadily closing, and the threat was averted. Can we do the same with the CO2 emissions that cause global warming?