Ozone layer depletion is a decline in the level of ozone gas (O3) present in the earth's stratosphere, owing to its breakdown into oxygen (O2). This breakdown can be affected by natural processes, but is known to have been accelerated by the release of man-made chemicals, such as refrigerant gases. The ozone layer acts to reduce the amount of light at ultra-violet wavelengths reaching the earth's surface; wavelengths that can have harmful impacts on humans, including skin cancer.
