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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

June 30, 2026

Researchers have discovered that beneficial soil bacteria give plants an unexpected survival advantage in salty soils. Instead of helping plants keep salt out, the microbes stimulate the production of lignin, a natural compound that strengthens ...
Hawaii researchers are giving old fishing nets and recycled plastic a second life by mixing them into asphalt roads. Early tests found these roads didn't release more plastic particles than standard pavement, with tire wear overwhelming any plastic ...
A surprising ecological makeover unfolded when mountain lions began frequenting a small preserve south of San Francisco. Deer activity dropped, plants recovered, and shifts among predators like coyotes, bobcats, and foxes followed. The study shows ...
A new study reveals that goldfish can do far more than survive in the wild—they can fundamentally reshape freshwater ecosystems. Researchers found they cloud water, damage food webs, and hurt native fish populations, sometimes triggering major ...
A Pacific-wide tsunami triggered by a magnitude 8.8 Kamchatka earthquake gave scientists their first detailed satellite view of a major tsunami in motion. The observations revealed unexpected wave behavior and helped uncover a larger earthquake ...
Researchers found that highly drug-resistant bacteria from hospitals are also resistant to glyphosate, a commonly used weedkiller. The discovery suggests that agricultural herbicides may be helping ...
Trees planted to protect farmland from wind may not be the biodiversity boost many assume. In Japan’s wetland farming landscapes, shelterbelts benefited some birds but sharply reduced grassland and wetland species that need open space. Researchers ...
Freshwater lakes across North America and Europe are becoming noticeably browner, reducing underwater visibility and reshaping fish populations. Research found that several popular sport fish, including trout, bass, perch, and whitefish, tend to ...
Scientists found that thawing permafrost can trigger increased rock weathering, a natural process that absorbs CO2 from the atmosphere. In some regions, this carbon uptake was strong enough to fully offset — or even surpass — river greenhouse ...
A historic lack of snow in the Gila River watershed has left Arizona’s San Carlos Reservoir less than 1% full, triggering a massive fish kill and an indefinite closure. Despite the bleak ...
A new study from Northern Arizona University is raising red flags about a widely used global emissions database from Climate TRACE, a consortium co-founded by Al Gore. Researchers found that the database may be dramatically undercounting carbon ...
A major study of Australian native bees found that stem-nesting species may be the first to feel the impact of climate change. Unlike bees that nest underground, they have few ways to escape dangerous heat. Researchers also discovered that tropical ...

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