On the SO sub(2) and NO sub(2) interferences in total ozone measurements made with the Dobson spectrophotometer No. 118 in Athens

The estimation of the error in the total ozone measurements made with the Dobson spectrophotometer in Athens caused by interfering urban pollutants (i.e., SO sub(2) , NO sub(2) ), is attempted. The 17-year period (1974-1990) data of radiosonde temperature profiles obtained at Hellinikon Airport, Athens, as well as the 2-year period 1989-1990 data for the SO sub(2) and NO sub(2) concentration in Athens have been used to examine the extent of the error in the total ozone measurement made with the Dobson spectrophotometer, installed in Athens, since 1989. The error in Dobson total ozone measurement in Athens due to SO sub(2) interference in general reaches the level of 1[small solid circle] 9 per cent while that due to NO sub(2) interference reaches the level of 1 per cent. This finding is in close agreement with recently published results.