Effect of El Niño on inter-annual variability of ozone during the period 1978-2000 over the Indian subcontinent and China

Abstract

The paper details the ozone trend over the Indian subcontinent and China inferred from multi-satellite sensors. The present study utilizes data from Nimbus-7, Earth Probe-Total Ozone Mapping Spectrometer (TOMS) and the more recently launched Global Ozone Monitoring Experiment (GOME) sensors. The inter-annual variability of total ozone column (TOC) has been analysed for two periods, from 1979-1993 measured by TOMS and 1996-2000 measured by TOMS and GOME for different Indian cities and Lhasa in Tibet and Beijing in China. The trend was found to be declining over all the major cities with different rates over the period 1979-1993, whereas over the period 1996-2000 the trend was found to increase. The effect of El Niño in 1997-98 on TOC is discussed in light of the prevailing sea surface temperature (SST) anomaly over the Indian Ocean and the Arabian Ocean.