Researchers study how climate change affects crops in India

Kyle Davis is an environmental data scientist whose research seeks to increase food supplies in developing countries. He combines techniques from environmental science and data science to understand patterns in the global ...

Bees required to create an excellent blueberry crop

Getting an excellent rabbiteye blueberry harvest requires helpful pollinators—particularly native southeastern blueberry bees—although growers can bring in managed honey bees to do the job, according to Agricultural Research ...

From rain to flood

Extreme weather events such as thunderstorms, heavy rainfall and resulting floods, influence Earth and environmental systems in the long term. To study the impacts of hydrological extremes holistically—from precipitation ...

NOAA upgrades the U.S. global weather forecast model

NOAA's flagship weather model—the Global Forecast System (GFS)—is undergoing a significant upgrade today to include a new dynamical core called the Finite-Volume Cubed-Sphere (FV3). This upgrade will drive global numerical ...

Solar activity forecast for next decade favorable for exploration

The last astronauts of the Apollo program were lucky. Not just because they were chosen to fly to the moon, but because they missed some really bad weather en route. This wasn't a hurricane or heat wave, but space weather—the ...

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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