Related topics: climate change · earth · climate models · climate · sunlight

New record set for lowest temperature—38 picokelvins

A team of researchers affiliated with several institutions in Germany and two in France has set a new record for the lowest temperature ever recorded in a lab setting—38 picokelvins. In their paper published in the journal ...

Large effect of Solar activity on Earth's energy budget

This is the result of a new study by researchers from DTU Space at the Technical University of Denmark (DTU) and of The Hebrew University of Jerusalem, who have traced the consequences of eruptions on the Sun on clouds and ...

Does pollution make thunderstorms more severe?

A team of atmospheric scientists from around the nation is descending on the Houston, Texas, area for the next 14 months to seek answers to a vexing question: Do tiny specks of soot, dust, smoke, and other particles suspended ...

Volcanic ash cloud closes La Palma airport; new vent emerges

The airport on the Spanish island of La Palma shut down Saturday because of an ash cloud spewing out of a volcano that has been erupting for a week, and scientists said another volcanic vent opened up, exposing islanders ...

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Cloud

A cloud is a visible mass of droplets or frozen crystals suspended in the atmosphere above the surface of the Earth or another planetary body. A cloud is also a visible mass attracted by gravity, such as masses of material in space called interstellar clouds and nebulae. Clouds are studied in the nephology or cloud physics branch of meteorology.

On Earth the condensing substance is typically water vapor, which forms small droplets or ice crystals, typically 0.01 mm in diameter. When surrounded by billions of other droplets or crystals they become visible as clouds. Dense deep clouds exhibit a high reflectance (70% to 95%) throughout the visible range of wavelengths. They thus appear white, at least from the top. Cloud droplets tend to scatter light efficiently, so that the intensity of the solar radiation decreases with depth into the gases, hence the gray or even sometimes dark appearance at the base. Thin clouds may appear to have acquired the color of their environment or background and clouds illuminated by non-white light, such as during sunrise or sunset, may appear colored accordingly. In the near-infrared range, clouds look darker because the water that constitutes the cloud droplets strongly absorbs solar radiation at those wavelengths.

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