Space-time variability of ozone over the Indian region for the period 1981-1998

Abstract

The space-time variability of monthly mean total column ozone (TCO) over India has been studied for the period of 18 years from 1981 to 1998. TCO data at four stations, New Delhi (28.31°N, 77.12°E), Varanasi (25.20°N, 83.00°E), Pune (18.31°N, 73.55°E), and Kodaikanal (10.13°N, 77.36°E), Quasi-Biennial Oscillation (QBO) index data of 30 hPa at Singapore (1°N, 103°E), and F10.7 cm solar flux and Southern Oscillation index data for the above period are used in the study. The effects of the Quasi-Biennial Oscillation, solar cycle, and volcanic eruptions (El Chichon of 1982, Mount Pinatubo of 1991) on ozone variations have been examined. The multiple regression analysis and singular spectrum analysis of ozone time series (1981-1998) for four stations showed good association between ozone and global forcing parameters, namely QBO and solar cycle. TCO and QBO showed significant negative correlations for New Delhi, Varanasi, and Pune and positive correlation for Kodaikanal. All the stations showed significant positive correlations between TCO and solar flux. Copyright 2003 by the American Geophysical Union.