Ozone Hole — Mains Strategy

Mains Strategy

Begin by defining the ozone hole as seasonal stratospheric depletion, not an atmospheric void. Explain the mechanism in a short causal chain, connecting long-lived source gases with polar chemistry and returning sunlight. This establishes why international controls on production and consumption can matter even though the visible depletion occurs far from many emission sources.

Use the Montreal Protocol's 1987 adoption to connect science and coordinated action. Add Kigali's 2016 HFC phasedown as a climate-policy extension while preserving the distinction between warming and ozone depletion. Then discuss why atmospheric lifetimes, compliance and meteorological variability make recovery gradual and require continued observation.

If using the 2022 assessment, state the 1980 baseline and the relevant geographical projection rather than listing years without context. A balanced conclusion is that treaty action can change the long-term chemical trajectory, while monitoring is needed to distinguish that trajectory from seasonal variability. Avoid claiming that a small hole in one year proves the problem solved or that a large hole disproves the policy mechanism.