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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

June 22, 2026

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 ...
Researchers discovered that hydrogen radicals generated by intense UV light can break down stubborn PFAS “forever chemicals” without added chemicals. The breakthrough reveals a key mechanism that could lead to greener and more effective ...
NASA satellites have detected a vast pulse of warm water reaching the coast of South America, signaling that El Niño is likely developing. The warm water is being carried eastward by massive ocean waves known as Kelvin waves, which also cause sea ...
Beneath our feet lies a vast hidden fungal superhighway that helps sustain much of life on Earth—and scientists have now mapped it for the first time. Researchers estimate that these underground networks stretch an astonishing 110 quadrillion ...
A new catalyst design could significantly improve the conversion of CO2 into methanol, an important fuel and chemical feedstock. Researchers separated key reaction steps across different catalyst sites, avoiding a long-standing trade-off between ...
One of the most celebrated claims about Yellowstone’s wolves is facing a major challenge. Scientists say the study behind the famous trophic cascade story relied on flawed methods that overstated the ecological impact of wolf recovery. Their ...
Alaska’s glaciers are proving to be highly sensitive to warming temperatures. Using radar satellites to monitor more than 3,000 glaciers, researchers found that every 1°C (1.8°F) increase in average summer temperature extends glacier melting by ...

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