Chlorofluorocarbons or CFCs are a chemical compound containing carbon, chlorine, and fluorine. Throughout the 20th century, CFCs were mass produced for their popularity in refrigeration and spray cans. In the 1970s, evidence began to show the harmful effects of CFCs on Earth.
Originally created as Great Sand Dunes National Monument on March 17, 1932, Great Sand Dunes National Park and Preserve was established by an act of the United States Congress on September 13, 2004.
in Western Australia: Relief. 1  To the south of the Kimberley region stand the 26-to-30-foot (8-to-9-metre) linear sand dunes of the Great Sandy Desert. Although the main period of dune formation ended about 10,000 years ago, the dune crests are still active (shifting).