Related topics: air pollution · air quality · pollution

Exploring the neurological impact of air pollution

Air pollution has become a fact of modern life, with a majority of the global population facing chronic exposure. Although the impact of inhaling polluted air on the lungs is well known, scientists are just now beginning ...

World needs 'green recovery', health experts tell G20 leaders

Trillions of dollars, euros and yuan pouring into post-pandemic economies must build a "healthy and green recovery", 200 medical groups representing 40 million health professionals worldwide told G20 leaders Tuesday in an ...

How well do Germans understand weather risks?

Many Germans have difficulty gauging the negative impact of weather conditions such as ground frost, heat, or UV radiation. This is one of the key results of a representative survey conducted by researchers at the Max Planck ...

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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.

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