Explosive origins of 'secondary' ice—and snow

Where does snow come from? This may seem like a simple question to ponder as half the planet emerges from a season of watching whimsical flakes fall from the sky—and shoveling them from driveways. But a new study on how ...

Legume trees key to supporting tropical forest growth

Researchers have found that nitrogen-fixing legume trees can support themselves and surrounding trees not only with increased access to nitrogen, but with other key nutrients through enhanced mineral weathering.

ATLAS project finds 12 new species of sea creatures

Researchers working with the ATLAS project have reported to the press that they have found 12 new species of sea creatures new to science. The EU funded undersea project has been ongoing for five years and has carried out ...

Space weather discovery puts 'habitable planets' at risk

A discovery that links stellar flares with radio-burst signatures will make it easier for astronomers to detect space weather around nearby stars outside the Solar System. Unfortunately, the first weather reports from our ...

Ancient blanket made with 11,500 turkey feathers

The ancient inhabitants of the American Southwest used around 11,500 feathers to make a turkey feather blanket, according to a new paper in the Journal of Archaeological Science: Reports. The people who made such blankets ...

Arctic transitioning to a new climate state

The fast-warming Arctic has started to transition from a predominantly frozen state into an entirely different climate, according to a comprehensive new study of Arctic conditions.

How cold was the ice age? Researchers now know

A University of Arizona-led team has nailed down the temperature of the last ice age—the Last Glacial Maximum of 20,000 years ago—to about 46 degrees Fahrenheit (7.8 C).

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Weather

Weather is a set of all the phenomena occurring in a given atmosphere at a given time. Weather phenomena lie in the troposphere. Weather refers, generally, to day-to-day temperature and precipitation activity, whereas climate is the term for the average atmospheric conditions over longer periods of time. When used without qualification, "weather" is understood to be the weather of Earth.

Weather occurs due to density (temperature and moisture) differences between one place and another. These differences can occur due to the sun angle at any particular spot, which varies by latitude from the tropics. The strong temperature contrast between polar and tropical air gives rise to the jet stream. Weather systems in the mid-latitudes, such as extratropical cyclones, are caused by instabilities of the jet stream flow. Because the Earth's axis is tilted relative to its orbital plane, sunlight is incident at different angles at different times of the year. On Earth's surface, temperatures usually range ±40 °C (100 °F to −40 °F) annually. Over thousands to hundreds of thousands of years, changes in Earth's orbit affect the amount and distribution of solar energy received by the Earth and influence long-term climate

Surface temperature differences in turn cause pressure differences. Higher altitudes are cooler than lower altitudes due to differences in compressional heating. Weather forecasting is the application of science and technology to predict the state of the atmosphere for a future time and a given location. The atmosphere is a chaotic system, so small changes to one part of the system can grow to have large effects on the system as a whole. Human attempts to control the weather have occurred throughout human history, and there is evidence that human activity such as agriculture and industry has inadvertently modified weather patterns.

Studying how the weather works on other planets has been helpful in understanding how weather works on Earth. A famous landmark in the Solar System, Jupiter's Great Red Spot, is an anticyclonic storm known to have existed for at least 300 years. However, weather is not limited to planetary bodies. A star's corona is constantly being lost to space, creating what is essentially a very thin atmosphere throughout the Solar System. The movement of mass ejected from the Sun is known as the solar wind.

This text uses material from Wikipedia, licensed under CC BY-SA