Related topics: air pollution · air quality · pollution

Summer swelter: Persistent heat wave breaks records, spirits

From the normally chilly Russian Arctic to the traditionally sweltering American South, big swaths of the Northern Hemisphere continued to sizzle with extreme heat as the start of summer more resembled the dog days of August ...

Water receding slowly in flood-hit northeast Bangladesh

Water levels were slowly receding Thursday in major rivers in Bangladesh's flood-hit northeast, bringing hopes of relief to millions of Bangladeshis, but woes continued in India's northeast, where 5.5 million people remained ...

Default options facilitate faster carbon offsetting in air travel

The defaults on a carbon offsetting website can cause a large percentage of customers to select faster CO2 compensation, even if this entails higher costs. In cooperation with a web portal offering carbon offsetting, a research ...

Not enough or too far? California climate plan pleases few

Heat waves and drought gripping California highlight the urgency to slash fossil fuel use and remove planet-warming emissions from the air, a top state official said Thursday during discussions of a new plan for the state ...

European map of aerosol pollution can help improve human health

Researchers have measured the composition of fine dust at 22 locations in Europe. The result of this international study, led by the Paul Scherrer Institute PSI, is a European map of the most important aerosol sources. The ...

Tackling air quality and COVID-19 in the classroom

As the days get colder, teachers not only face the usual seasonal battle of keeping classrooms at a comfortable temperature but also trying to reduce the COVID-19 virus count in the environment. How to reduce virus spread ...

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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