Earths physcical systems
Living in Physical Systems Analytical Processes The following presentation will firstly identify key issues that need to be addressed in order to sustain the environment. Secondly the causes and effects of the key issues will be analysed. The Earth supports three non-living physical systems: the atmosphere, lithosphere and hydrosphere. Together they form a variety of environments called the biosphere. The Biosphere is the earth¡¯s thin zone of air, soil and water that is capable of supporting life, ranging from about 10km into the atmosphere to the deepest ocean floor. Life in this zone depends on the sun¡¯s energy and on the circulation of heat and essential nutrients. The atmosphere is a mixture of gases surrounding the Earth that has a gravitational field strong enough to prevent gases from escaping. The principal elements of the atmosphere are nitrogen (78%) and oxygen (21%). The atmospheric gases in the remaining 1% are argon, carbon dioxide as well as tiny amounts of neon, helium, krypton, nitrous oxide and water vapour.