The ozone breakdown, which also occurs to some extent in the middle latitudes, has led to a steady depletion of the ozone layer over the past few decades. The beneficial role of stratospheric ozone arises from its capacity to absorb solar radiation in a particular ultraviolet range, UVB, thus protecting living cells on the Earth's surface against UVB rays' destructive action. Ozone is the only atmospheric compound, when it is present in sufficient quantities, capable of absorbing UVB rays in this wavelength range