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What happens to molecular chlorine when sunlight returns to Antarctica in spring?

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ozone depletion — Ozone depletion The Antarctic ozone hole reaches its maximum extent in October of each year. On October 7, 2021, when this image was captured, the Antarctic ozone hole spanned 24.8 million square km (9.6 million square miles).

When sunlight returns to Antarctica in the early spring, it breaks the accumulated molecular chlorine ( $C l_{2}$ ) into single chlorine atoms. These highly reactive atoms then participate in a catalytic cycle that strips oxygen atoms from ozone molecules, leading to significant ozone destruction. This process continues until the polar vortex breaks up, typically in November.1