6.2: Stratospheric Ozone

why is the stratospheric ozone important?

it controls the temperature of the atmosphere; it protects living systems from the negative effects of ultraviolet radiation from the Sun

ozone depleting substances

chlorofluorocarbons

hydrofluorocarbons

halons

methyl bromide

nitrogen oxides

sources of chlorofluorocarbons

aerosols

gas-blown plastics (e.g. an air conditioner)

pesticides

flame retardants

refrigerants

how do ozone-depleting substances harm the ozone?

chlorine atoms react with ozone or oxygen, leading to ozone destruction and contributes to the greenhouse effect

what effect does ultraviolet radiation have on humans?

damages human living tissues

increases risks of cataracts (damages eyes)

skin cancer, sunburn

cell mutation (which can lead to cancer)

what effect does ultraviolet radiation have on plants?

damages productivity in photosynthetic organisms; especially phytoplankton

decreases the rate of photosynthesis

causes mutation

increases susceptibility to disease

pollution management strategies

altering human behaviour:

using alternatives to gas-blown plastics, halogenated pesticides, propellants and aerosols

reduce or replace pesticides

regulation of pollutants:

recover and recycle CFCs

National legislation

ban on the production and use of ozone-depleting substances

clean up and restoration:

add ozone or remove heroine from stratosphere