Long-term ozone trend and its effect on night airglow intensity of Li 6708 Å at Ahmedabad (23°N, 72.5°E), India and Halley Bay (76°S, 27°W), British Antarctic Service Station

Abstract

A critical analysis has been made of the long-term yearly and seasonal variations of ozone concentration at Ahmedabad (23°N, 72.5°E), India and Halley Bay (76°S, 27°W), a British Antarctic Service Station. The effect of O3 depletion on night airglow emission of Li 6708 A line at Ahmedabad and Halley Bay has been studied. Calculations based on chemical kinetics show that the airglow intensity of Li 6708 A line has also been affected due to the depletion of O3 concentration. The nature of yearly variation and seasonal variation of intensity of Li 6708 A line for the above two stations have been shown and compared. It has been shown that the rate of decrease of intensity of Li 6708 A line was comparatively higher at Halley Bay due to dramatic decrease of Antarctic O3 concentration.