INFOGRAFICA INTERATTIVA Smog, come sono variate le emissioni di PM10 negli anni

This natural color image released 02 May, 2005 by NASA shows Saturn moon Titan's upper atmosphere, an active place where methane molecules are being broken apart by solar ultraviolet light and the byproducts combine to form compounds like ethane and acetylene. The haze preferentially scatters blue and ultraviolet wavelengths of light, making its complex layered structure more easily visible at the shorter wavelengths used in this image. Lower down in the atmosphere, the haze turns into a globe-enshrouding smog of complex organic molecules. This thick, orange-colored haze absorbs visible sunlight, allowing only perhaps 10 percent of the light to reach the surface. The thick haze is also inefficient at holding in and then re-radiating infrared (thermal) energy back down to the surface. Thus, despite the fact that Titan has a thicker atmosphere than Earth, the thick global haze causes the greenhouse effect there to be somewhat weaker than it is on Earth. AFP PHOTO/HO/NASA (Photo by HO / NASA / AFP)