NDLI: What made the hole in the ozone go away?

Content Provider	Science Questions with Surprising Answers
Description	According to NASA, the hole appears and disappears every year due to a complex interplay of seasonal weather patterns. Ozone blocks most of the harmful ultraviolet rays from the sun, which would otherwise reach earth's surface and cause more skin cancer. The hole in the ozone, which in reality is more like a region of partial depletion than a complete hole, was dangerously increasing in size in the 1980's and 1990's. Research indicated that use of man-made CFC chemicals such as found in aerosol cans contributed to depleting the ozone. As a result the U.S. banned the use of CFC's in aerosol cans in 1978.
File Format	HTM / HTML
Language	English
Publisher Date	2012-12-17
Requires	HTML5 supported browser
Access Restriction	Open
Subject Keyword	Cfc Chemical Hole in The Ozone Ozone Ozone Hole Regulation Chemistry Chemistry Questions and Answers Chemistry Questions Chemistry Questions Answers Questions on Chemistry Topics with Answers Questions on Chemistry General Question on Chemistry Science Questions with Answers
Content Type	Text
Educational Role	Student Teacher
Educational Use	Reading Classroom Solution Self Learning
Education Level	Class XI Class IX Class XII Class X
Resource Type	Model Answer Question
Subject	Chemistry

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What made the hole in the ozone go away?