Popis: |
For a proper understanding of long term trends in atmospheric ozone concentrations, the availability of high quality data sets is of great importance. At present, total ozone column densities are routinely measured by the ground based Dobson, Brewer and M-83/124 filter ozonometer networks, as well as by satellite based instruments such as the Total Ozone Mapping Spectrometer (TOMS). Vertical concentration profiles are obtained by ground based Umkehr methods, balloon borne electrochemical ozone sondes and by satellite based limb path atmospheric extinction measurements, such as the Stratospheric Aerosol and Gas Experiments (SAGE I/II). |