Stratospheric ozone depletion is primarily driven by emissions of_______________?
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Answer: B. Chlorofluorocarbons
Explanation
Chlorofluorocarbons release reactive chlorine atoms when broken down by ultraviolet radiation. These free chlorine atoms catalytically destroy stratospheric ozone molecules in a continuous cycle. This chemical destruction creates significant thinning within the protective ozone layer. The stratosphere is an upper layer of Earth's atmosphere containing protective ozone concentrations. Ozone absorbs harmful ultraviolet radiation from the sun, protecting life on the surface. Synthetic chemicals were widely used in refrigeration and aerosol propellants for decades.
Stratospheric ozone depletion increases human skin cancer rates and harms aquatic ecosystems. Global environmental treaties successfully phased out chlorofluorocarbons to heal the ozone layer. Atmospheric science monitors ozone levels to ensure ongoing recovery of polar regions. Carbon dioxide is a greenhouse gas driving climate change rather than stratospheric ozone depletion. UV rays are electromagnetic radiation blocked by ozone rather than the chemical cause of depletion. Deforestation increases atmospheric carbon dioxide levels but does not directly deplete stratospheric ozone.
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