Spatial and temporal variation of total ozone over East Asia and Europe: An inter-comparison

Using the daily data of TOMS (Total Ozone Mapping Spectrometer) from 1979 t o 1994, the spatial and temporal variations of total ozone over East Asia ( 69.375 degreesE similar to 139.375 degreesE; 14.5 degreesN similar to 54.5 degreesN) and the west part of Europe (20.625 degreesW similar to 40.625 de greesE; 35.5 degreesN similar to 70.5 degreesN) were analyzed to make an in tercomparison. Results showed that the mean ozone concentrations over the t wo regions similarly evolved in one year, with sinusoid curves which reache d a maximum in spring (March for East Asia, April for Europe), and a minimu m in autumn (October and November for East Asia and Europe respectively). W ith a higher annual mean concentration over Europe, the amplitude of season al variation was also larger in comparison to those of East Asia. Annual me an ozone concentrations showed obviously decreasing trends during the perio d from 1979 to 1994, over both regions, but the net reduction over Europe w as approximately twice the amount as over East Asia. Spatial distribution p attern of total ozone showed clear differences over the two regions, as wel l as their seasonal evolution.