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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

March 21, 2026

A mysterious spike of platinum buried deep in Greenland’s ice has long fueled theories of a catastrophic comet or asteroid strike 12,800 years ago—possibly triggering a sudden return to icy conditions known as the Younger Dryas. But new research ...
Tropical peatlands, some of the planet’s largest underground carbon stores, are now burning at levels never seen in at least 2,000 years. By analyzing charcoal preserved in peat across multiple continents, scientists discovered that fires had ...
Pink granite boulders sitting mysteriously atop Antarctica’s Hudson Mountains have led scientists to a stunning discovery: a hidden granite mass buried beneath Pine Island Glacier, stretching nearly 100 km wide and 7 km thick. By dating the rocks ...
AI’s growing energy use sounds alarming, but its global climate impact may be far smaller than expected. Researchers found that while AI consumes huge amounts of electricity, it barely moves the needle on overall emissions. The real impact is more ...
The asteroid impact that wiped out the dinosaurs didn’t keep life down for long. New research shows that microscopic plankton began evolving into new species within just a few thousand years—and possibly in under 2,000 years—after the ...
Spiders and insects may not be fan favorites, but they are vital to the health of ecosystems—and scientists barely know how they’re doing. Researchers found that nearly 90% of North America’s insect and arachnid species have no conservation ...
Researchers have uncovered a universal pattern showing how temperature affects life on Earth. Across thousands of species—from microbes to reptiles—performance rises gradually with warming until an optimal temperature is reached, after which it ...
Decades of data from over 80,000 great tits reveal that extreme weather can shape the fate of baby birds. Cold snaps soon after hatching and heavy rain later in development shrink nestling body mass and reduce survival odds. But moderate warm spells ...
As deep-sea waters warm, scientists expected trouble for the microbes that help keep ocean chemistry in balance. Instead, researchers found that Nitrosopumilus maritimus can adapt to warmer, iron-limited conditions by using iron more efficiently. ...
Global warming has picked up speed in the past decade, according to a new analysis from the Potsdam Institute for Climate Impact Research (PIK). By removing short term natural influences such as El Niño, volcanic eruptions, and solar cycles from ...
Scientists have discovered a newly identified marine fungus that can infect and kill toxic algae responsible for harmful blooms. The microscopic parasite, named Algophthora mediterranea, attacks algae such as Ostreopsis cf. ovata, which produces ...
Ocean temperatures may be quietly protecting the world from a global drought catastrophe. By analyzing more than a century of climate data, researchers discovered that droughts rarely spread across the planet at the same time, affecting only about ...

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