WW2010
University of Illinois

WW2010
 
  welcome
 
> online guides
 
  archives
 
  educational cd-rom
 
  current weather
 
  about ww2010
 
  index

Online Guides
 
  introduction
 
> meteorology
 
  remote sensing
 
  reading maps
 
  projects, activities

Meteorology
 
  introduction
 
  air masses, fronts
 
  clouds, precipitation
 
  el nino
 
  forces, winds
 
  hurricanes
 
  hydrologic cycle
 
> light, optics
 
  midlatitude cyclones
 
  severe storms
 
  weather forecasting

Light, Optics
 
  introduction
 
  mechanisms
 
> air, dust, haze
 
  ice crystals
 
  water droplets

air, dust, haze
 
  crepuscular rays
 
> blue skies, blue haze
 
  sunsets

User Interface
 
  graphics
> text

NOTE: We've guessed that you're not using a client that supports colored tables and have tried to compensate. Low graphics mode looks much better on clients that do... we recommend switching to Netscape 3.0 or Microsoft Internet Explorer.
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Blue Skies and Blue Haze
resulting from selective scattering by air molecules

Blue skies are produced as shorter wavelengths of the incoming visible light (violet and blue) are selectively scattered by small molecules of oxygen and nitrogen -- which are much smaller than the wavelength of the light. The violet and blue light has been scattered over and over by the molecules all throughout the atmosphere, so our eyes register it as blue light coming from all directions, giving the sky its blue appearance.

[Image: a blue sky (64K)]
Photograph by: Holle

Blue haze is a phenomenon commonly observed in the Smoky Mountains of eastern Tennessee and the Blue Ridge Mountains of Virginia.

[Image: blue haze (68K)]
Photograph by: Young

As tiny hydrocarbon particles released by vegetation chemically react with ozone molecules, they produce particles that selectively scatter blue light, giving the mountains their blue appearance.



crepuscular rays
Terms for using data resources. CD-ROM available.
Credits and Acknowledgments for WW2010.
Department of Atmospheric Sciences (DAS) at
the University of Illinois at Urbana-Champaign.

sunsets