EFFECT OF BANDWIDTH ON FILTER INSTRUMENT TOTAL OZONE ACCURACY.

Abstract

The effect of the width and shape of the New Zealand filter instrument's passbands on total ozone accuracy measured by spectrophotometer is determined using a numerical model of the spectral measurement process. The model enables the calculation of corrections for the ″handwidth-effect″ error and shows that highly attenuating passband skirts and well-suppressed leakage bands are at least as important as narrow half-bandwidths. Over typical ranges of airmass and total ozone, the range in the bandwidth-effect correction is about 2% in X//A//D for the filter instrument, compared to about 1% for the Dobson instrument.