Total Column Ozone Measurements at Visakhapatnam Using Microtops - II Sun-photometer

The results of the continuing systematic measurements of the total column ozone over Visakhapatnam are given. It has been shown that the total column ozone varies within a wide range during a day, a season, and from year to year. It is found that the total column ozone is minimum in winter and maximum in summer. Measurements of atmospheric total column ozone over Visakhapatnam (17.43N, 83.14E) are being carried out first time using Microtops – II (sun photometer) for the period from February 2005 to till date, but the results are presented for three years (i.e.) from February 2005 to December 2007, to study the systematic behavior of the total column ozone. The data obtained during the study period, have been analyzed to study diurnal and seasonal variations of the total column ozone over Visakhapatnam. The results show that the total column ozone is maximum at noon time and minimum in the evening time in almost all the cloud free days. The daily and seasonal variations of total column ozone over Visakhapatnam indicate that total ozone values are low in winter season and high in summer season. It is observed that the monthly averaged column ozone over Visakhapatnam is maximum (336.0Du (Dobson Units)) in May and minimum (273.8 Du) in December. The monthly variations in the column ozone mostly depend on temperature which controls the chemical and dynamical processes related to the photochemical reactions in the atmosphere.