Planetary Boundary Nr 1: Stratospheric Ozone Layer

The stratospheric ozone layer filters out ultraviolet radiation from the sun. If this layer decreases, increasing amounts of ultraviolet (UV) radiation will reach ground level and can cause a higher incidence of skin cancer in humans as well as damage to terrestrial and marine biological systems. The appearance of the Antarctic ozone hole was proof that increased concentrations of anthropogenic ozone depleting substances, combined with polar stratospheric clouds, had moved the Antarctic stratosphere into a new regime. Fortunately, because of the actions taken as a result of the Montreal Protocol, we appear to be on the path that will allow us to stay within this boundary.

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