GEOG 2050 Chapter : Chapter 1 2
Document Summary
Degassing atmosphere: about 3. 8 billion years ago: earth cools and solid crust forms, dissolved gases from molten rock are releases to the atmosphere. Early atmosphere: 60% to 70% h2o, 10% to 15% co2, 8% to 10% n2, no free oxygen. Heavy precipitation period: about 3. 6 billion years ago: earth continues to cool, water vapor condenses and clouds form, rains for thousands of years and creates oceans, most co2 removed from the atmosphere to form limestone (caco2) Naturally occurring: not man-made of from life: chemical processes (o3, h2, n2, geologic (n2, ar, ne, he, kr, xe) Biological: photosynthesis, respiration, and decomposition (o2, co2, ch4, Man-made: (n2o, co2, ch4, o3) and other pollutants. The atmosphere: 99. 9% of the atmospheric mass lies below 31 miles (50km, 90% lies below 10 miles (16km, 50% lies below 3. 5 miles (5. 5km) Early manned balloon flight: 1862, fainted from lack of oxygen at high elevations.
