The ozone layer is a layer of ozone high up in the Earth's atmosphere stratosphere. ... This radiation is dangerous to many living organisms on Earth. Over the last hundred years the ozone layer has been damaged by man-made chemicals, especially ones called CFCs (chlorofluorocarbons). CFCs were used for various purposes. The ozone hole. The term 'ozone hole' refers to the depletion of the protective ozone layer in the upper atmosphere (stratosphere) over Earth's polar regions. ... Stratospheric ozone is constantly produced by the action of the sun's ultraviolet radiation on oxygen molecules (known as photochemical reactions.
Ozone is a gas in the atmosphere that protects everything living on the Earth from harmful ultraviolet (UV) rays from the Sun. Without the layer of ozone in the atmosphere, it would be very difficult for anything to survive on the surface.
An ozone molecule consists of three oxygen atoms (O3), whereas the stable form of oxygen that normally exists in the atmosphere consists of only two. When certain chemical processes make an extra oxygen atom available, the highly reactive atom binds readily with an oxygen molecule. Ozone is also highly reactive, and its oxidizing ability is second only to fluorine. It is useful as a deodorizing and bleaching agent as well as for killing germs and purifying water. It is a pale blue gas at room temperature, and its strong odor is reminiscent of a thunderstorm because lightning strikes produce ozone.
Ozone depletion would magnify all of the effects of UV on human health, both positive (including production of vitamin D) and negative (including sunburn, skin cancer, and cataracts). In addition, increased surface UV leads to increased tropospheric ozone, which is a health risk to humans.