ESTIMATION OF OZONE WITH TOTAL OZONE PORTABLE SPECTRORADIOMETER INSTRUMENTS .2. PRACTICAL OPERATION AND COMPARISONS

We used a microcomputer-controlled total ozone portable spectroradiome ter instrument #21 (MTOPS21) to measure solar radiation at 298, 304 an d 310 nm in Greenbelt, Md., during 1995. One day's ozone measurements ii-om a Brewer instrument (B105) were used to calibrate the 304- and 3 10-nm channel ratios to a theoretical model. Total ozone estimates wer e then determined for the entire MTOPS21 data set. Differences between individual B105 and MTOPS21 ozone estimates show a 1% drop as solar z enith angles increase and depend on atmospheric attenuation and SO2 va riation at the +/-2% level. Daily average values agree well. (<0.5% av erage offset, 2% standard deviation). (C) 1996 Optical Society of Amer ica