Search

The total amount of ozone in a vertical column has been measured spectroscopically at near ultraviolet and visible wavelengths, using ground- and satellite-based instruments. The vertical distribution of ozone from the surface up to approximately 100 km has been measured by a variety of techniques - chemical and optical - and from a number of observing platforms, including balloon, rocket, and satellite platforms. The various methods presently used for determining the atmospheric ozone distribution are reviewed, along with a discussion of their advantages and disadvantages. The observed average distribution of total ozone for the period 1958-1975 shows the expected geographic and seasonal variations. The variations of total ozone, including hemispheric differences, are clearly associated with large-scale circulation processes in the lower stratosphere. Approximately ten years of observations of the vertical ozone distribution, up through the ozone maximum, also show geographic and seasonal variations strongly related to the lower stratosphere circulation. The distribution above the maximum, however, results from the interaction of photochemistry and stratospheric motions.

Observations of backscattered radiation from an orbiting geophysical observatory (Ogo) satellite for the period September 1967 to February 1968 have been used to determine the global distribution of ozone at different levels in the middle and upper stratosphere (30-55 km). The derived distributions show significant seasonal and geographic variations with important differences indicated between winter and summer hemisphere distributions. The Ogo-derived distributions are compared with other observations (rocket and satellite) and with photochemical calculations. It is suggested that the increased ozone mixing ratio in the high-latitude winter hemisphere can be accounted for by transport processes up to about 40-45 km and by temperature-sensitive chemistry above.

Results are summarized from three areas of ozone research: (1) continued analysis of the global distribution of total ozone to extend the global ozone atlas to summarize 15 years (1957-72) of ground based observations; (2) analysis of balloon borne ozonesonde observations for Arosa, Switzerland, and Hohenpeissenberg, Germany (GFR); (3) contined processing of the (Orbiting Geophysical Observatory-4) satellite data to complete the analysis of the stratospheric ozone distribution from the available OGO-4 data. Results of the analysis of the total ozone observations indicated that the long term ozone variation have marked regional patterns and tend to alternate with season and hemisphere. It is becoming increasingly clear that these long period changes are associated with large scale variations in the general upper atmosphere circulation patterns.

The annual variation of the total amount of ozone over central Switzerland and the partial pressures in each of 7 layers from the surface to 7.8 m zeta shows the pattern representative of mid-latitude ozone: summer maximum in the troposphere, spring maximum in the lower stratosphere up to 30 mb and summer maximum in the middle stratosphere up to approx. mb. It was also shown that at the level of the ozone maximum the ozone partial pressure has a pronounced period of about 26 months. Total ozone and the ozone concentration in the different layers have marginally significant (at plus or minus sigma) correlations with relative sunspot number. The time lag for these correlations is long in the troposphere (about 36 months) but decreases with height to the level of ozone maximum (to about 2 months). A similar analysis of the data derived from the ozonesonde program at Hohenpeissenberg, Germany (GFR) gave completely consistent results with those discussed above.

Observations of backscattered radiation from an Orbiting Geophysical Observatory (OGO) Satellite were used to determine the global distribution of ozone in different layers in the middle and upper stratosphere. The derived distributions show significant seasonal and geographic variations with important differences indicated between winter and summer hemisphere distributions. The OGO derived distributions are compared with other observations (rocket and satellite) and with photochemical calculations. It is suggested that the increased ozone mixing ratio in the high latitude winter hemisphere can be accounted for by transport processes up to about 40-45 km and by the effects of seasonal variations of NOX, HOX and temperature in the region above.

Ozone vertical distribution in upper stratosphere determined from OGO 4 observations, describing calibration of satellite data and onboard instrumentation