A new study is warning intense summer thunderstorms are posing a major threat to the ozone layer. Scientists at Harvard University found strong thunderstorms are sending water deep into the stratosphere, setting off ozone-depleting reactions with chemicals that remain from the now-banned cooling gases known as chlorofluorocarbons, or CFCs. The study warns that the ozone layer could suffer more damage should global warming unleash ongoing intense storms. Ozone is key to survival on earth, protecting people, animal and crops from the ultraviolet rays of the sun. The study is said to be one of the first to draw a deep link between ozone loss and climate change. On Thursday, a fierce storm tore through areas of the northeastern United States, knocking out power to more than 200,000 homes and businesses.