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Reference Terms
from Wikipedia, the free encyclopedia

Ozone layer

The ozone layer is the part of the Earth's atmosphere which contains relatively high concentrations of ozone (O3). "Relatively high" means a few parts per million - much higher than the concentrations in the lower atmosphere but still small compared to the main components of the atmosphere. Although the concentration of ozone in the ozone layer is very small, it is vitally important to life because it absorbs biologically harmful ultraviolet (UV) radiation from the Sun. The "thickness" of the ozone layer - that is, the total amount of ozone in a column overhead - varies by a large factor worldwide, being in general smaller near the equator and larger as one moves towards the poles. It also varies with season, being in general thicker during the spring and thinner during the autumn.

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Earth & Climate News

July 22, 2026

Ancient fern savannahs may have transformed parts of Europe into a wildfire-prone inferno during the end-Triassic mass extinction. New fossil evidence suggests the ferns repeatedly regrew after fires, creating fresh fuel that helped prolong the ...
Ancient sediment reveals that some of K’gari’s deepest lakes vanished around 7,500 years ago, despite unusually heavy rainfall. The surprising discovery suggests changing winds and future climate ...
China’s Chang’e-6 samples have uncovered a surprising difference between the Moon’s two hemispheres. Solar wind particles penetrated deeper into the far-side soil because Earth’s ...
Oxygen is disappearing from oceans, lakes, rivers, and coastal waters at an alarming rate, threatening aquatic life and weakening the natural processes that help regulate Earth’s climate. Scientists warn that this widespread deoxygenation is ...
The asteroid that wiped out the dinosaurs was likely an exceptionally rare CO chondrite from a distant region of the solar system. Its unusual chemistry suggests that planet-cooling dust and debris, ...
Scientists have found evidence that a major Cascadia earthquake could trigger a second quake on the San Andreas Fault. The discovery came from unusual sediment layers formed by underwater landslides ...
A catastrophic asteroid breakup may have triggered a huge wave of impacts across the inner solar system about 800 million years ago. The debris was launched from near a gravitational gateway controlled by Jupiter, sending fragments toward Earth, the ...
Seismic waves have revealed that the oceanic plate beneath the Ontong Java Plateau was dramatically transformed by the colossal volcanic activity that created it more than 100 million years ago. Researchers found a complex structure of horizontal ...
Tiny plastic particles in drinking water may be doing more than contaminating the environment. New research suggests nanoplastics can actually help harmful bacteria survive by strengthening the slimy biofilms they form inside water systems. These ...
A major DNA study has rewritten the koala's evolutionary story, revealing that the species suffered a dramatic population collapse about 100,000 years ago, long before humans arrived in Australia. By calculating the koala's mutation rate for the ...
Researchers have created self-destructing living plastic that uses engineered bacteria to completely break itself down when activated. The material degrades in just six days without creating ...
Scientists have identified a hidden feedback loop that may explain how Earth has regulated its climate for tens of millions of years. As sea levels rose and fell, they changed how much phosphate reached the open ocean, affecting marine life and the ...

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