Can Natural Changes Such As the Suns Output and Volcanic Eruptions Be Responsible for the Observed Changes in Ozone?
Although there are natural forces that cause fluctuations in ozone amounts, there is no evidence that natural changes are contributing significantly to the observed long-term trend of decreasing ozone. The formation of stratospheric ozone is initiated by ultraviolet (UV) light coming from the Sun. As a result, the Sun’s output affects the rate at which ozone is produced. The Sun’s energy release (both as UV light and as charged particles such as electrons and protons) does vary, especially over the well-known 11-year sunspot cycle. Observations over several solar cycles (since the 1960s) show that total global ozone levels vary by 1-2% from the maximum to the minimum of a typical cycle. However, changes in the Sun’s output cannot be responsible for the observed long-term changes in ozone, because the ozone downward trends are much larger than 1-2%. As the figure below shows, since 1978 the Sun’s energy output has gone through maximum values in about 1980 and 1991 and minimum values in
Although there are natural forces that cause fluctuations in ozone amounts, there is no evidence that natural changes are contributing significantly to the observed long-term trend of decreasing ozone. The formation of stratospheric ozone is initiated by ultraviolet (UV) light coming from the Sun. As a result, the Sun’s output affects the rate at which ozone is produced. The Sun’s energy release (both as UV light and as charged particles such as electrons and protons) does vary, especially over the well-known 11-year sunspot cycle. Observations over several solar cycles (since the 1960s) show that total global ozone levels vary by 1-2% from the maximum to the minimum of a typical cycle. However, changes in the Sun’s output cannot be responsible for the observed long term changes in ozone, because the ozone downward trends are much larger than 1-2%. As the figure below shows, since 1978 the Sun’s energy output has gone through maximum values in about 1980 and 1991 and minimum values in
