Related topics: air pollution · air quality · pollution

New Delhi announces plan to combat winter toxic air

A plan to combat air pollution in New Delhi was announced by authorities Friday, as the Indian capital looks to lighten the toxic smog blanket that chokes the city, especially in winter.

'Fire inversions' lock smoke in valleys

Smoke from a summer wildfire is more than just an eye-stinging plume of nuisance. It's a poison to the lungs and hearts of the people who breathe it in and a dense blanket that hampers firefighting operations.

Beijing to exit 200 most polluted cities list

Beijing's notoriously bad air quality has improved in recent years and the Chinese capital is expected to drop out of a list of 200 most polluted cities in the world this year, a data provider said Thursday.

Malaysia piles pressure on Indonesia over smog-belching fires

Malaysia has stepped up pressure on neighboring Indonesia to tackle huge blazes tearing through its rainforests and smothering Southeast Asia in smog, as fires typically started to clear land for crops send diplomatic tensions ...

Optical vacuum cleaner can manipulate nanoparticles

Scientists at Tomsk Polytechnic University jointly with Russian and international colleagues developed the concept for constructing an "optical vacuum cleaner." Due to its optical properties, it can trap nanoparticles from ...

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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