Quantifying past, present and future Stratospheric and Tropospheric Ozone over the Alps and Europe

Ozone in the atmosphere is a strong absorber of solar ultraviolet radiation, thereby acting as a shield to protect us and Earth's biosphere from this harmful radiation. Manmade chemicals containing halogen compounds released into the atmosphere since the middle of the last century were determined to be responsible for the observed depletion of the ozone residing in the stratosphere, where most of the ozone is located. The Montreal Protocol and its amendments have led to decreases in the atmospheric abundance of those controlled ozone-depleting substances, which has led to increases in the upper-stratospheric ozone. However, no significant trend in total column ozone has been detected in middle latitudes so far. The total column ozone recovery since the 1990’s, especially at northern mid-latitudes is expected to be complex, with a timeline depending on many factors.