After decades of destruction by humanity, the ozone layer is actually beginning to recover. A United Nations panel reported Wednesday that for the first time in 25 years, scientists documented a statistically significant and sustained increase in the stratospheric ozone. Ozone is a type of oxygen that blocks harmful solar radiation. The regrowth is largely due to the phase-out of certain chemicals in aerosol cans and refrigerants in the 1980s. It is a heartening sign that united global efforts can combat environmental crises. “It’s a victory for diplomacy and for science and for the fact that we were able to work together,” said chemist Mario Molina.