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

NASA tests new ride for science studies from Wallops

NASA will test a new capability for supporting science research in the mesosphere with the launch of two rockets from NASA's Wallops Flight Facility, Virginia on Feb. 9, 2023. The two Improved-Orion suborbital sounding rockets ...

What uncertainties remain in climate science?

The favored refrain of climate deniers and those who oppose climate policies is that "the science is not settled." To some degree, this is true. Climate scientists are still uncertain about a number of phenomena. But it is ...

The chaotic cores of Perseus protostars

The formation of a star has a simple tale. A region of interstellar gas collapses under its own weight, eventually forming a dense protostar surrounded by a disk of gas and dust. The protostar and the disk rotate in the same ...

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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