Clean Air
   Air is everywhere. We breathe it and it surrounds us. For most of human existence air has been thought to be infinite. In the early 1960s photographs made by satellites and astronauts confirmed the modern view that the earth's atmosphere is finite. We live in an ocean of air extending upward perhaps 1,000 miles. A thin, narrow band of air, from 5 to 11 miles thick, lies next to the earth and is the region of continuous winds. Were it not for wind the component gases of our air would separate into layers.

     Air is highly compressible. The first three-and-one-half miles of earth's atmosphere comprise one-half of earth's air by weight. Within this nearby blanket of heavy air most of earth's weather changes occur.

   Technology is the tool which has allowed us to understand air and weather and the human-caused impacts on both. Technology has provided insight into how contaminated air adversely affects our health. Technology has given us the means to pollute the air and the means to control and to limit contamination of the air.

     Air currents can be a source of enjoyment, too. The area near Petersburg is highly regarded nationally for its "Petersburg Wave," which is a glider pilot's thrill and delight. A prevailing westerly wind whips across the 4,000- foot plateau which encompasses Dolly Sods and Roaring Plains. As the wind reaches the eastern rim of the plateau, it plummets down the steep Allegheny Front into a broad valley. Once at the bottom, the air shoots upward in a wave powerful enough to elevate gliders as high as 26,000 feet.

Last updated on Monday, March 26, 2001