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

Clouds in the southern hemisphere more precisely understood

Clouds in the southern hemisphere reflect more sunlight than those in the northern hemisphere. The reason is a more frequent occurrence of liquid water droplets, which results from an interplay between updrafts and a cleaner ...

Huge Tonga volcanic eruption caused 'significant damage'

A massive volcanic eruption in Tonga that triggered tsunami waves around the Pacific caused "significant damage" to the island nation's capital and smothered it in dust, but the full extent was unclear with communications ...

Biomass burning increases low clouds over southeastern Asia

Clouds have significant impact on the energy balance of the Earth system. Low clouds such as Stratocumulus, Cumulus and Stratus cover about 30 percent of the Earth surface and have a net cooling effect on our climate. What ...

Coherent interstellar magnetic field detected

Magnetic fields are the essential, but often "secret" ingredients of the interstellar medium and the process of making stars. The secrecy shrouding interstellar magnetic fields can be attributed to the lack of experimental ...

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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