Ozone — Montreal Protocol, Kigali Amendment (HFCs)

UPSC tests Montreal Protocol as the world's most successful environmental treaty with near-universal ratification. Questions focus on ozone-depleting substances (ODSs), phase-out timelines, and the Kigali Amendment's addition of HFCs as climate-relevant chemicals. Examiners target treaty mechanisms (fund, secretariat), India's role, and the distinction between ozone depletion and climate impact—avoid conflating CFC bans with CO2 reduction.