Related topics: air pollution · air quality · pollution

Western wildfire smoke plumes are getting taller

In recent years the plumes of smoke crawling upward from Western wildfires have trended taller, with more smoke and aerosols lofted up where they can spread farther and impact air quality over a wider area. The likely cause ...

China swelters under record heat

Cities across China were on red alert for heatwaves on Monday, as tens of millions of people were warned to stay indoors and record temperatures strained energy supply.

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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