AP BIOLOGY

Detailed explanation-1: -The ozone layer, which lies high in the atmosphere, shields us from harmful ultraviolet (UV) rays that come from the Sun. Human activities effectively punched a hole in it, through the use of gases like chlorofluorocarbons (CFCs) in spray cans and refrigerants, which break down ozone molecules in the upper atmosphere.

Detailed explanation-2: -Gaseous CFCs can deplete the ozone layer when they slowly rise into the stratosphere, are broken down by strong ultraviolet radiation, release chlorine atoms, and then react with ozone molecules. See Ozone Depleting Substance.)

Detailed explanation-3: -Once in the atmosphere, CFCs drift slowly upward to the stratosphere, where they are broken up by ultraviolet radiation, releasing chlorine atoms, which are able to destroy ozone molecules. The seasons have an impact on the Antarctic ozone hole.

Detailed explanation-4: -Why has the ozone hole developed? The ozone hole has developed because people have polluted the atmosphere with chemicals containing chlorine and bromine. The primary chemicals involved are chlorofluorocarbons (CFCs for short), halons, and carbon tetrachloride.

Detailed explanation-5: -Ozone depletion occurs when chlorofluorocarbons (CFCs) and halons-gases formerly found in aerosol spray cans and refrigerants-are released into the atmosphere (see details below).