Lecture 2 Atmosphere – its composition, extent and structure (English
Atmosphere – its composition, extent and structure Atmosphere The atmosphere is a multilayer gaseous envelope covering the earth from all sides, whose total mass is tons and its height above sea level is estimated from 16 to 29 thousand kilometers. Its mass density decreases with height. ü The atmosphere provides essential gases, heat, and water for all the plants and animals of the biosphere, due to which the earth has become a habitable area for all living beings. ü It absorbs the ultraviolet rays coming from the sun and prevents them from coming on the surface of the earth, thus the surface is saved from overheating. v Composition of Atmosphere 1. Gases 2. Water vapor 3. Suspended particulate matter or aerosols v Gases 1. Constant/permanent gases 2. Variable Gases v Constant/permanent gases ü Nitrogen in the atmosphere is 78.1, oxygen 20.9, argon 0.9 pe...