ozone layer

noun

|Updated on: 8 Aug 2018

Definition of ozone layer

: an atmospheric layer at heights of about 20 to 30 miles (32 to 48 kilometers) that is normally characterized by high ozone content which blocks most solar ultraviolet radiation from entry into the lower atmosphere

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Recent Examples of ozone layer from the Web

Over the second half of the 20th century, the Earth's ozone layer grew increasingly thinner, and in some places disappeared entirely.

— avery thompson, Popular Mechanics, "Investigation Finds China Behind Ozone-Damaging Mystery," 9 July 2018
Researchers said in a study published last month that a rise in emissions of CFC-11 was jeopardizing the effort to repair the ozone layer, which protects people and crops from the sun’s damaging ultraviolet rays.

— chris buckley, New York Times, "In a High-Stakes Environmental Whodunit, Many Clues Point to China," 24 June 2018
There is mercury in liquid-crystal display screens, lead in cathode-ray tubes, cadmium in semiconductors and batteries, and ozone layer-destroying chlorofluorocarbons in old refrigerators, for example.

— peter ford, The Christian Science Monitor, "'E-waste': Getting grip on a growing global problem," 9 July 2018
And is diverting billions of dollars to interplanetary travel the most important project in human history, or an incomprehensible waste of money at a time when there are so many terrestrial crises on this side of the ozone layer?

— derek thompson, The Atlantic, "Is Colonizing Mars the Most Important Project in Human History?," 29 June 2018
Passing directly beneath the hole in the ozone layer, Swan's face became badly burned and his eyes even changed color.

— christina capatides, CBS News, "Expedition Antarctica: A father and son's journey to save the planet," 22 June 2018
And all that loose chlorine was tearing up the ozone layer, ripping up the chemical bonds of high-flying molecules that protect Earth’s surface from ultraviolet radiation.

— rafi letzter, Scientific American, "Earth’s Ozone Layer is Under Attack—Again," 22 May 2018
Youngblood points out that their modeling assumes the flares from the star include powerful events called coronal mass ejections (CMEs), which would have a more destructive effect on a planet's magnetic fields and ozone layer.

— john wenz, Popular Mechanics, "An Ultra-Powerful Flare Erupted From Our Nearest Neighbor Star," 10 Apr. 2018
The ozone layer, a fragile shield of gas, protects animal and plant life on Earth from powerful UV rays.

— james griffiths, CNN, "Ozone-destroying emissions are on the rise and scientists don't know why," 16 May 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'ozone layer.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of ozone layer

1927

in the meaning defined above

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OZONE LAYER Defined for English Language Learners

ozone layer

noun

Definition of ozone layer for English Language Learners

: a layer of ozone in the upper atmosphere that prevents dangerous radiation from the Sun from reaching the surface of the Earth

OZONE LAYER Defined for Kids

ozone layer

noun

Definition of ozone layer for Students

: a layer of the earth's upper atmosphere that is characterized by high ozone content which blocks most of the sun's ultraviolet radiation from entering the lower atmosphere