On a good visibility day, Stony Man Mountain and nearby hills may be seen cleary with the human eye.
On a poor visibility day, both natural conditions and air pollution obscures your view of Stony Man Mountain and distant views beyond.
The Blue Ridge
The bluish haze that gave these Blue Ridge Mountains their name was produced largely by forest vegetation. Millions of trees, and countless leaves, emit great amounts of moisture and natural chemicals into the air. They react with sunlight to form a natural visible suspension, or haze.
Today, this natural haze is almost insignificant compared to human-caused pollutants. These unnatural pollutants produce a whitish or brownish haze that obscures your view of nearby and distant mountains. It is believed that this human-caused atmospheric pollution is also having an adverse effect on the natural ecosystems in Shenandoah National Park.
Power generating facilities, industrial boilers and current forms of transportation emit sulfur dioxide which is transformed in the atmosphere to sulfates. Sulfates account for more than 60% of the visible haze in Shenandoah. They are also linked to the formation of acid rain, Shenandoah's silent threat.
Acid rain has destroyed fish and plant life in hundreds of lakes and streams in the U.S. and Canada. Scientists believe that acid rain reduces plant growth and kills microorganisms in soils. It also releases metals from the soil which concentrate in the root system and damage the plant's ability to absorb water and available nutrients.