Smoky Mountain haze

The Great Smoky Mountains are so named because of a haze that is usually present. This is caused by hydrocarbon emissions from trees. The concentrations are sometimes so high that the forest areas are in violation of the clean air standards... 

Atmospheric Effects. The presence of fine particles (0.1-1.0 mm in diameter) or N02 in the atmosphere can result in atmospheric haze or reduced visibility due to light scattering by the particles. The major effect of atmospheric haze has been degradation in visual air quality and is of particular concern in areas of scenic beauty, including most of the major national parks such as Great Smoky Mountain, Grand Canyon, Yosemite, and Zion Parks. 

The haze over the Smoky Mountains is caused by aerosols produced by the oxidation of hydrocarbons emitted by pine trees. 

The haze of the Smoky Mountains is caused by light-scattering from the aerosol produced by the photooxidation of isoprene and other hydrocarbons. 

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