An article published Friday in Science reports that the Antarctic ozone hole 
is healing. As the article notes, there was some previous evidence about global improvement in stratospheric ozone levels, but this is the first to document improvement in Antarctica.
Aside from the fact that good news is always welcome, it’s also a useful reminder that environmental regulation can work. In the developed world, with sophisticated environmental regulation, air is cleaner, water is cleaner, and the land is less contaminated than 50 years ago. Work is of course, not done (see, e.g., Flint). There’s also that pesky climate change issue.
Nonetheless, progress is progress, and should be recognized and celebrated.