UV rays strongest this time of year, Environment Canada warns
By Contributor
This is the time of the year when ultraviolet rays that cause sunburn and skin cancer are unusually high, Environment Canada warns.
Record ozone loss above the Arctic this past winter has been caused by ozone-destroying chemicals such as chlorofluorocarbons and halons left over from before the Montreal Protocol.
That was the international agreement signed in 1987 to phase out those chemicals, which were used in products such as refrigerators, aerosol spray cans, fire extinguishers.
Climate change is producing conditions in the atmosphere that enhance ozone-destroying chemical reactions.
Greenhouse gases are trapping heat close to the surface of the Earth, preventing it from reaching the stratosphere above, where the ozone layer is found.
Colder temperatures in the stratosphere boost ozone depletion.
