Some learners may think that
- there is a layer of ozone high up in the atmosphere
- there is/are one or more holes in the layer
The atmosphere is (largely) gases, which will freely mix. The recognised 'layers' in the atmosphere relate primarily to different physical properties (such as temperature), but there are no absolute divisions as gases (and water droplets, dust, etc.) move between 'layers'.
The 'ozone layer' is not a layer of ozone, but refers to the part of the atmosphere where the presence of ozone (as one small component of the mixture of gases) is active in absorbing radiation which could be harmful if it reached ground level.
Depletion of the ozone in the 'ozone layer' (due to reaction with synthetic compounds* such as the chlorofluorocarbons, CFCs, that were historically produced for applications such as refrigeration because of their great stability and low toxicity – and which had escaped into the atmosphere at ground level and diffused to higher altitudes) did not occur uniformly, but predominantly in polar regions due to the presence of clouds that facilitate the reactions, so that ozone concentrations in these regions were much lower (up to about 60% depletion at its most extreme) than in other parts of the 'layer'. The so-called 'holes' were thus regions of substantially lower concentration, but were not areas with no ozone at all.
So, there is an 'ozone layer' but it is not a layer of ozone, and 'holes in the ozone layer' form, but they are not actually holes.
* Some ozone depletion also occurs naturally, so ozone concentrations may fall after major volcanic eruptions.
Read about the nature of alternative conceptions
Read about some examples of science misconceptions
Read about historical scientific conceptions
[Please be aware that a word may have different nuances, or even a different meaning, according to context.]« Back to Index
