Related topics: air pollution · air quality · pollution

Hot weather linked to rise in early childbirth: study

Hot weather can cause a spike in the number of babies being born early, a phenomenon that may harm infant health and is likely to get worse as temperatures climb due to climate change, scientists said Monday.

Smog in Iran shuts schools, universities

Air pollution forced the closure of schools and universities in parts of Iran on Saturday, including Tehran, which was cloaked by a cloud of toxic smog, state media reported.

S. Korea to suspend 25% of coal plants to fight pollution

South Korea will suspend up to a quarter of its coal-fired power plants in the next three months, even as demand for electricity peaks during the bitter winter, as it seeks to tackle air pollution, Seoul said Thursday.

Life, liberty—and access to microbes?

Poverty increases the risk for numerous diseases by limiting people's access to healthy food, environments and stress-free conditions. In a new essay published November 26 in the open-access journal PLOS Biology, Suzanne ...

NASA soil data joins the Air Force

Getting stuck on a muddy road is a hassle for anyone, but for the U.S. Army it could be far more serious—a matter of life and death in some parts of the world. That's one of the reasons the U.S. Air Force HQ 557th Weather ...

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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