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Environmental Science

The Role of Ozone in Tropospheric and Stratospheric Chemistry

Quick fact

Ozone is found in two different regions of the atmosphere: the stratosphere (10-50 km up) and the troposphere (the layer we live in). At ground level, ozone is a component of photochemical smog and is harmful to breathe, while the stratospheric ozone layer protects life by absorbing 97-99% of the Sun's ultraviolet radiation.

Why this is interesting

You've heard of the ozone layer, but did you know that ozone can be a dangerous pollutant? The same molecule that shields us from the Sun's harmful rays can also harm our lungs and contribute to smog. How can that be?