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from Wikipedia, the free encyclopedia

Earth's atmosphere

Earth's atmosphere is a layer of gases surrounding the planet Earth and retained by the Earth's gravity. It contains roughly 78% nitrogen and 21% oxygen 0.97% argon and carbon dioxide 0.04% trace amounts of other gases, and water vapor. This mixture of gases is commonly known as air. The atmosphere protects life on Earth by absorbing ultraviolet solar radiation and reducing temperature extremes between day and night.

The atmosphere has no abrupt cut-off. It slowly becomes thinner and fades away into space. There is no definite boundary between the atmosphere and outer space. Three-quarters of the atmosphere's mass is within 11 km of the planetary surface..

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Earth & Climate News

February 7, 2026

Arctic sea ice helps cool the planet and influences weather patterns around the world, but it is disappearing faster than ever as the climate warms. Scientists have now developed a new forecasting method that can predict how much Arctic sea ice will ...
A new study reveals that chemicals used to replace ozone-damaging CFCs are now driving a surge in a persistent “forever chemical” worldwide. The pollutant, called trifluoroacetic acid, is falling out of the atmosphere into water, land, and ice, ...
Melting ice from West Antarctica once delivered huge amounts of iron to the Southern Ocean, but algae growth did not increase as expected. Researchers found the iron was in a form that marine life could not easily use. This means more melting ice ...
Researchers have found that manganese, an abundant and inexpensive metal, can be used to efficiently convert carbon dioxide into formate, a potential hydrogen source for fuel cells. The key was a clever redesign that made the catalyst last far ...
As demand for critical metals grows, scientists have taken a rare, close look at life on the deep Pacific seabed where mining may soon begin. Over five years and 160 days at sea, researchers documented nearly 800 species, many previously unknown. ...
SAR11 bacteria dominate the world’s oceans by being incredibly efficient, shedding genes to survive in nutrient-poor waters. But that extreme streamlining appears to backfire when conditions change. Under stress, many cells keep copying their DNA ...
Scientists studying ancient ocean fossils found that the Arabian Sea was better oxygenated 16 million years ago, even though the planet was warmer than today. Oxygen levels only plunged millions of years later, after the climate cooled, defying ...
Small mammals are early warning systems for environmental damage, but many species look almost identical, making them hard to track. Scientists have developed a new footprint-based method that can tell apart nearly indistinguishable species with ...
Scientists have created a device that captures carbon dioxide and transforms it into a useful chemical in a single step. The new electrode works with realistic exhaust gases rather than requiring purified CO2. It converts the captured gas into ...
After analyzing 40 years of tree records across the Andes and Amazon, researchers found that climate change is reshaping tropical forests in uneven ways. Some regions are steadily losing tree species, especially where conditions are hotter and ...
A new building material developed by engineers at Worcester Polytechnic Institute could change how the world builds. Made using an enzyme that turns carbon dioxide into solid minerals, the material cures in hours and locks away carbon instead of ...
Mountain regions around the world are heating up faster than the lands below them, triggering dramatic shifts in snow, rain, and water supply that could affect over a billion people. A major global review finds that rising temperatures are turning ...

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