Ozone layer declining over populated zones: study

The ozone layer that protects life on Earth from deadly ultraviolet radiation is unexpectedly declining above the planet's most populated regions, according to a study released Tuesday.Nearly three decades later, the "ozone hole" over the South Pole and the upper reaches of the stratosphere are showing clear signs of recovery."In tropical and middle latitudes" -- home to most of humanity -- "the ozone layer has not started to recover yet," lead author William Ball, a researcher at the Swiss Fede