PowerPoint PresentationSlide 2Slide 3Slide 4Slide 5Slide 6Slide 7Slide 8Slide 9Slide 10Slide 11The Earth’s AtmosphereOxygenNitrogenArgonWater VaporCarbon DioxideMethaneOzoneComposition of the AtmosphereComposition of the AtmosphereList of primary gasses in Earth’s AtmosphereKeeping Earth warm…Atmosphere composed on O2 and N2 onlyAtmosphere composed on O2 and N2 and greenhouse gasses1. 2BUT…Avg. global surface air temperature without GHG =Avg. global surface air temperature with GHG =The human thermometer…Liquid Gas (can’t see)SolidDefinition of Temperature:Measuring TemperatureDevice used to measure temperature = Figure 1.1Vostok, AntarcticaThe relationship between Temperature and Density The higher the air temperature, the faster the air molecules move The faster the molecules move, the more space they will need to move aroundWarming the air will cause it to expandCooling the air will cause it to contractGeneral Temperature VariationsUneven surface heating drives atmospheric circulationsKey Idea: Mother nature constantly tries to get to equilibrium.Caused by:1. 1. Avg. Surface Air Temperature =Seasonal Variations in TemperatureSummer Solstice:Autumnal Equinox:Winter Solstice:Vernal Equinox:23.5°NH summerNH wintercloserJune 21st. Sun’s rays are direct on the Tropic of Cancer (23.5°N) Most daylight hoursNH autumnSeptember 21st. Sun’s rays are direct on the Equator 12 hrs of daylight and 12 hrs of nightDec 21st. Sun’s rays are direct on the Tropic of Capricorn (23.5°S) Least daylight hoursNH springMarch 21st. Sun’s rays are direct on the Equator 12 hrs of daylight and 12 hrs of night*** The tilt of the Earth on its axis causes the Sun’s rays to become more (or less) direct which concentrates (or disperses) the Sun’s energy throughout the yearSeasons: The effects of latitudeWhy? Winter:Summer:12°N Nyala Sudan, Africa: Jan= July=40°N Urbana, Illinois, USA: Jan= July=66°N Verkhoyansk Russia: Jan= July=Tropic of Cancer 23.5°NEquator 0°Arctic Circle 66.5°NTop of atmosphereProximity to large bodies of waterUrbana, ILSan Francisco, CADover, DEhighest sun and greatest insolationwarmest time of year (mid-continent)warmest time of year (west coast)Vertical Temperature Variations“Lid”Aurora BorealisMeteor