Psychology & Psychiatry

Nerve cell activity shows how confident we are

Should I or shouldn't I? The activity of individual nerve cells in the brain tells us how confident we are in our decisions. This is shown by a recent study by researchers at the University of Bonn. The result is unexpected—the ...

Health

Hurricane safety: Preparing for cleanup before the storm

Severe weather has many parts of the U.S. on high alert as two storms are expected to make landfall this week. Now is the time to double-check that you are prepared and start thinking about safety after the storm.

Diseases, Conditions, Syndromes

Dry air increases COVID risk: Another reason to wear a mask

A study published in June focused on the Greater Sydney area during the early epidemic stage of COVID-19 found an association between lower humidity and an increase in community transmission.

Diseases, Conditions, Syndromes

Tips to keep ticks under control this summer

Summertime brings an abundance of good things—sunshine, warm weather, backyard cookouts and fire pits—but, like it or not, summertime also brings out some pesky creatures that could put a damper on your plans and health.

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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