Global Efforts Lead to Ozone Layer Recovery and Climate Action Progress
The global transition away from chlorofluorocarbons (CFCs) and hydrofluoroalkanes (HFAs) has marked a significant milestone in environmental protection. According to the source, the Montreal Protocol, established in 1987 and amended in 1991, successfully phased out CFCs by 2000, leading to a decline in atmospheric chlorine levels and a stabilization of the Antarctic ozone hole. By 2025, NASA and NOAA reported the ozone hole as the fifth smallest since satellite records began in 1992. However, HFAs, which replaced CFCs, have high global warming potential (GWP), prompting the Kigali Amendment in 2016 to phase down their use by 80–85% by the 2040s. This effort could prevent up to 105 billion metric tons of CO2-equivalent emissions and limit global warming by 0.5°C by 2100. Despite setbacks like unreported emissions and climate events, the long-term trend shows stabilization and recovery of the ozone layer. 
