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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

January 26, 2026

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 ...
Plastic-coated fertilizers used on farms are emerging as a major but hidden source of ocean microplastics. A new study found that only a tiny fraction reaches beaches through rivers, while direct drainage from fields to the sea sends far more ...
Tiny plastic particles drifting through the oceans may be quietly weakening one of Earth’s most powerful climate defenses. New research suggests microplastics are disrupting marine life that helps oceans absorb carbon dioxide, while also releasing ...
New research shows tropical forests can recover twice as fast after deforestation when their soils contain enough nitrogen. Scientists followed forest regrowth across Central America for decades and found that nitrogen plays a decisive role in how ...
In the rapidly disappearing Atlantic Forest, mosquitoes are adapting to a human-dominated landscape. Scientists found that many species now prefer feeding on people rather than the forest’s diverse wildlife. This behavior dramatically raises the ...
For thousands of years, wildfires on Alaska’s North Slope were rare. That changed sharply in the 20th century, when warming temperatures dried soils and fueled the spread of shrubs, setting the stage for intense fires. Peat cores and satellite ...
Scientists have identified a newly recognized threat lurking beneath the ocean’s surface: sudden episodes of underwater darkness that can last days or even months. Caused by storms, sediment runoff, algae blooms, and murky water, these “marine ...
Earth’s oceans reached their highest heat levels on record in 2025, absorbing vast amounts of excess energy from the atmosphere. This steady buildup has accelerated since the 1990s and is now driving stronger storms, heavier rainfall, and rising ...
Honey bees can normally keep their hives perfectly climate-controlled, but extreme heat can overwhelm their defenses. During a scorching Arizona summer, researchers found that high temperatures caused damaging temperature fluctuations inside hives, ...
Scientists tracking Earth’s water from space discovered that El Niño and La Niña are synchronizing floods and droughts across continents. When these climate cycles intensify, far-apart regions can become unusually wet or dangerously dry at the ...

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