Health

Air pollution contributes significantly to diabetes globally

New research links outdoor air pollution—even at levels deemed safe—to an increased risk of diabetes globally, according to a study from Washington University School of Medicine in St. Louis and the Veterans Affairs (VA) ...

Arthritis & Rheumatism

What makes joints pop and crack and is it a sign of disease?

Joints emit a variety of noises, including popping, snapping, catching, clicking, grinding, grating and clunking. The technical term for these noises is "crepitus", from the Latin "to rattle". People of all ages can experience ...

Oncology & Cancer

More than 2,500 cancer cases a week could be avoided

More than 135,500 cases of cancer a year in the UK could be prevented through lifestyle changes, according to new figures from a Cancer Research UK landmark study published today.

Cardiology

Air pollution exposure linked to enlarged hearts

Healthy people exposed to even low levels of air pollution over a handful of years developed enlarged heart chambers, a common precursor to heart failure, a new study indicates.

Diseases, Conditions, Syndromes

Why polluted air may be a threat to your kidneys

There is good evidence that polluted air increases the risk of respiratory problems such as asthma—as well as organ inflammation, worsening of diabetes and other life-threatening conditions.But new research suggests air ...

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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