News tagged with air

Related topics: air pollution · air quality · pollution

Clean air for our future

Preterm birth is the leading cause of infant death and long-term neurological disease, and 1 in 10 infants born in the United States is affected by preterm birth according to the Centers for Disease Control and Prevention. ...

Nov 10, 2016
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Fragranced products: Risks for people and profits?

A University of Melbourne researcher has found that over one-third of Americans report health problems—from asthma attacks to migraine headaches—when exposed to common fragranced consumer products such as air fresheners, ...

Oct 24, 2016
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Earth's atmosphere

The Earth's atmosphere is a layer of gases surrounding the planet Earth that is retained by the Earth's gravity. It has a mass of about five quadrillion metric tons. Dry air contains roughly (by volume) 78.08% nitrogen, 20.95% oxygen, 0.93% argon, 0.038% carbon dioxide, and trace amounts of other gases. Air also contains a variable amount of water vapor, on average around 1%. The atmosphere protects life on Earth by absorbing ultraviolet solar radiation, warming the surface through heat retention (greenhouse effect), and reducing temperature extremes between day and night.

There is no definite boundary between the atmosphere and outer space. It slowly becomes thinner and fades into space. An altitude of 120 km (75 mi) marks the boundary where atmospheric effects become noticeable during atmospheric reentry. The Kármán line, at 100 km (62 mi), is also frequently regarded as the boundary between atmosphere and outer space. Three quarters of the atmosphere's mass is within 11 km (6.8 mi; 36,000 ft) of the surface.

This text uses material from Wikipedia, licensed under CC BY-SA

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