Answers to questions about ozone depletion and the recovery of the ozone hole are now easy to find by researchers, as well as the general public, through a new online index developed by NOAA’s Earth System Research Laboratory. The site uses simple graphs and charts to track progress in reducing the threat to Earth’s ozone layer—the protective shield that prevents harmful ultraviolet radiation from reaching the surface. A new chart shows which of the harmful gases are declining, which are still increasing, and the overall effect of these changes. Scientists will update the index every year using new data collected from NOAA’s global observation network.