Noxon Cliff

Noxon Cliff

Noxon Cliff (77°32′S 163°5′E / 77.533°S 163.083°E / -77.533; 163.083) is an east-west trending cliff at the south end of Flint Ridge in Asgard Range, Victoria Land. The cliff encloses the north flank of Commonwealth Glacier where it rises from 50 to 150 m above the glacier. Named by Advisory Committee on Antarctic Names (US-ACAN) (1997) after John F. Noxon, who pioneered the technique of visible spectroscopy for measurements of stratospheric trace gases, particularly nitrogen dioxide. By 1975, he began making measurements of nitrogen dioxide column as a function of latitude, and was surprised to discover an abrupt decrease in the amounts in Arctic air as compared to values observed at lower latitudes. This unexpected phenomenon, width implications for later ozone depletion studies, became known as the "Noxon cliff". In 1978, Noxon sailed on RV Hero from Ushuaia, and quickly confirmed that a "cliff" in nitrogen dioxide is also found in the Antarctic atmosphere.

 This article incorporates public domain material from the United States Geological Survey document "Noxon Cliff" (content from the Geographic Names Information System).