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Reference Terms
from Wikipedia, the free encyclopedia

Weather

Weather is a term that encompasses phenomena in the atmosphere of a planet. The term is normally taken to mean the activity of these phenomena over short periods of time, usually no more than a few days. Average atmospheric conditions over significantly longer periods are known as climate. Usage of the two terms often overlaps and the physical concepts underlying them are closely related. On Earth, regularly occurring weather phenomena include such things as wind, cloud, rain, snow, fog and dust storms. Less common events include natural disasters such as tornadoes, hurricanes and ice storms. Almost all familiar weather phenomena occur in the troposphere (the lower part of the atmosphere). Weather does occur in the stratosphere and does affect weather lower down in the troposphere, but the exact mechanisms are poorly understood.

The Earth's atmosphere is a chaotic system, so small changes to one part can have large effects elsewhere. This makes it very difficult to accurately predict weather changes more than a few days in advance, though weather forecasters are continually working to extend this limit through the scientific study of weather, meteorology.

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Earth & Climate News

July 19, 2026

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, ...
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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 ...
NASA's PACE satellite captured the Black Sea glowing turquoise during its annual phytoplankton bloom. The vivid color comes from massive numbers of coccolithophores, microscopic organisms whose reflective shells brighten the water enough to be seen ...
The world's longest-running soil warming experiment has revealed an unexpected climate concern. After nearly four decades, researchers found that warming can cause microbes to break down stable soil carbon that scientists once believed was largely ...
Scientists discovered that extreme deep-sea pressure squeezes valuable nutrients out of sinking organic particles, providing an unexpected food source for ocean microbes. The finding could rewrite our understanding of both deep-ocean ecosystems and ...
Why do beaches today have seashells from clams and snails instead of brachiopods? A new study suggests the answer lies in Earth's greatest mass extinction, when warming oceans and falling oxygen levels wiped out animals that couldn't adapt. Species ...

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