position.ppt

Chapter two Atmospheric Atmospheric Structure position Structure position 1. Atmospheric Structure ?? The atmosphere The atmosphere ?? Atmospheric Structure Atmospheric Structure ?? Troposphere Troposphere ?? Stratosphere Stratosphere ?? Mesosphere Mesosphere ?? Thermosphere Thermosphere ?? Ionosphere Ionosphere ?? atmospheric pressure atmospheric pressure ?? Wind and pressure Wind and pressure ?? Atmospheric Circulation Atmospheric Circulation The atmosphere ?? The atmosphere is a thin blanket of gas that The atmosphere is a thin blanket of gas that envelops the earth. envelops the earth. ?? The gases that make up the atmosphere are held The gases that make up the atmosphere are held close to the earth by the pull of gravity. close to the earth by the pull of gravity. ?? With increasing distance from the earth With increasing distance from the earth ’’ s surface, the s surface, the temperature, density, position of the temperature, density, position of the atmosphere gradually change atmosphere gradually change ?? On the basis of On the basis of air temperature air temperature , the atmosphere can , the atmosphere can be divided vertically into four major layers. be divided vertically into four major layers. The atmosphere functions as ? A highly effective regulator of heat and radiation, the principal sources of energy for life. ? A radiator: Protects the biosphere (where life is found … about 21 km thick) from harmful forms of ing solar radiation ? As a heat regulator, the atmosphere slows the loss of heat from earth, a process called the GREENHOUSE EFFECT Atmospheric Structure Atmospheric Structure Troposphere ?? The troposphere is the layer from the earth The troposphere is the layer from the earth ’’ s surface to the s surface to the tropopause tropopause , which is at 10-15 km altitude depending on latitude , which is at 10-15 km altitude depending on latitude and time of year. (Mt. Everest ) and time of year. (Mt. Everest 8