Search results
Results from the WOW.Com Content Network
This process of reflection/absorption is what causes the range of cloud color from white to black. [19] Other colors occur naturally in clouds. Bluish-grey is the result of light scattering within the cloud. In the visible spectrum, blue and green are at the short end of light's visible wavelengths, while red and yellow are at the long end. [20]
This phenomenon leaves the Sun's rays, and the clouds they illuminate, abundantly orange-to-red in colors, which one sees when looking at a sunset or sunrise. For the example of the Sun at zenith, in broad daylight, the sky is blue due to Rayleigh scattering, which also involves the diatomic gases N 2 and O 2.
The Rayleigh sky causes a clearly defined polarization pattern under many different circumstances. The degree of polarization however, does not always remain consistent and may in fact decrease in different situations. The Rayleigh sky may undergo depolarization due to nearby objects such as clouds and large reflecting surfaces such as the ocean.
Skyglow is significantly amplified by the presence of snow, and within and near urban areas when clouds are present. [7] In remote areas, snow brightens the sky, but clouds make the sky darker. In remote areas on moonless nights clouds appear dark against the sky. In or near developed areas skyglow is strongly enhanced by clouds.
the cloud IR emissivity, with values between 0 and 1, with a global average around 0.7; the effective cloud amount, the cloud amount weighted by the cloud IR emissivity, with a global average of 0.5; the cloud (visible) optical depth varies within a range of 4 and 10. the cloud water path for the liquid and solid (ice) phases of the cloud particles
Noctilucent clouds are generally colourless or pale blue, [50] although occasionally other colours including red and green have been observed. [51] The characteristic blue colour comes from absorption by ozone in the path of the sunlight illuminating the noctilucent cloud. [52]
Particles in the air scatter short wavelength light (blue and green) through Rayleigh scattering much more strongly than longer wavelength yellow and red light. Loosely, the term "crepuscular rays" is sometimes extended to the general phenomenon of rays of sunlight that appear to converge at a point in the sky, irrespective of time of day.
Crepuscular rays usually appear orange because the path through the atmosphere at dawn and dusk passes through up to 40 times as much air as rays from a high Sun at noon. Particles in the air scatter short- wavelength light (blue and green) through Rayleigh scattering much more strongly than longer-wavelength yellow and red light.