Summary ESCI 1010 Chapter 2 Review

Chapter 2

 What is the atmosphere
o Function:
 Filter
 Insulation
 Reservoir
 Variable gases
o Water vapor
 Most abundant variable gas
 Added/removed to air through the hydrologic cycle
 Important to energy balance and many atmospheric processes
 Carbon dioxide
o A trace gas
 0.038% of atmosphere’s mass
 Important to Earth’s energy balance
o Added through biologic respiration, volcanic activity, decay, and
natural and human-related combustion
o Removed through photosynthesis
o Increasing at a rate of 1.8 ppm/year
 Temporal increases due to human activity
 Seasonal variations related to biological activity
 Ozone
o Oxygen
o Absorbs ultraviolet radiation
o Chlorofluorocarbons destroy ozone
o Destruction peaks over southern hemisphere
o Antarctic circumpolar vortex limits latitudinal mixing
 Aerosols
o Any solid and/or liquid particle, other than water
o Both natural and human sources
o Long residence times for some types
o Acts as condensation nuclei
 Vertical Structure of the Atmosphere
 Density and the atmosphere
o Density decreases rapidly with height
 The top of the atmosphere is undefined
 Majority of mass is compressed near the surface
 Thermal layers of the Atmosphere
o Four Distinct atmospheric layers
 Troposphere
 Stratosphere
 Mesosphere
 Thermosphere