In this video produced by ThinkTV, learn how the protective ozone layer is formed in the upper atmosphere, serving as a global sunscreen and protecting us from harmful ultraviolet rays. Changes in the ozone have been tracked for many years by scientists, who first observed ozone depletion in the 1970s. When research showed that holes in the ozone were caused by CFCs, commonly used in the manufacture of household products, many nations joined in a ban on their usage. Today, the ozone holes appear to be shrinking as scientists continue to monitor their progress.
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