Mission control 'saves science'

Every minute, ESA's Earth observation satellites gather dozens of gigabytes of data about our planet—enough information to fill the pages on a 100-metre long bookshelf. Flying in low-Earth orbits, these spacecraft are continuously ...

24 percent of West Antarctic ice is now unstable: study

By combining 25 years of European Space Agency satellite altimeter measurements and a model of the regional climate, the UK Centre for Polar Observation and Modelling (CPOM) have tracked changes in snow and ice cover across ...

First-ever constructed image of a terrestrial gamma-ray flash

Terrestrial gamma-ray flashes occur above some thunderstorms and propagate out into space. These high-energy discharges of photons were only discovered less than 25 years ago when a NASA spacecraft designed to observe cosmic ...

New potential for tracking severe storms

Even just within the last couple of months, Cyclones Fani, Idai and Kenneth have brought devastation to millions. With the frequency and severity of extreme weather like this expected to increase against the backdrop of climate ...

Study finds income affects bus ridership in bad weather

Temperature extremes and heavy rain reduce weekday bus ridership in Lane County, except in low-income neighborhoods where residents have few alternatives for transportation, according to a University of Oregon study.

Most EU countries cut CO2 emissions last year: estimates

Most European Union countries reduced carbon dioxide emissions last year, estimates showed Wednesday, marking a turnaround in the battle against greenhouse gases as campaigners urged faster action to avoid the most damaging ...

Recognising sustainable behaviour

Solving the growing problem of space debris will require everyone who flies rockets and satellites to adhere to sustainable practices, which doesn't always happen. Now there will be a way to recognise those who do.

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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