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

Study finds the West is best to spot UFOs

In July of 2023, retired commander in the U.S. Navy David Fravor testified to the House Oversight Committee about a mysterious, Tic Tac-shaped object that he and three others observed over the Pacific Ocean in 2004. The congressional ...

New cloud model could help with climate research

When clouds meet clear skies, cloud droplets evaporate as they mix with dry air. A new study involving researchers from the University of Gothenburg has succeeded in capturing what happens in a model. Ultimately, this could ...

Which came first: Black holes or galaxies?

Black holes not only existed at the dawn of time, they birthed new stars and supercharged galaxy formation, a new analysis of James Webb Space Telescope data suggests.

Hubble spots a galaxy shrouded by stars

This NASA/ESA Hubble Space Telescope image shows a densely packed field of stars laid upon a background of dust, gas, and light from more distant celestial objects. There are so many stars in this image's field of view that ...

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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