SPECTRAL MEASUREMENTS OF ULTRAVIOLET RADIATION OVER EASTERN SIBERIA DURING A TOTAL OZONE ANOMALY

A. V. Mikhalev, M. A. Chernigovskaya, A. Yu. Shalin, and A. B. Beletskii

Results of ground-based spectral measurements of UV radiation around midday in Eastern Siberia (Irkutsk) for 1997—1998 are presented. The instruments and technique are described. The time variations of the measured surface UV radiation level are analyzed, and a comparison with total ozone variations is made for the given period. An increase in seasonally averaged UV radiation for the spring of 1997 over Eastern Siberia is found during the ozone anomaly. The periods of 6—10 and 25 days in the UV radiation variations are identified.