Structure of the AtmosphereAtmospheric PressureAtmospheric Composition (CO2, CH4, H20, CFC’s, Aerosols)Temperature Anomaly: change in temp relative to mean tempIf climate is changing, how will this affect weather?Land, Weather, and Climate70% of earths surface is wateroceans help regulate global temperaturesoceans not distributed equally over surfacenorthern hemisphere will have most variation in weatherland surface will create instabilities in wind flowland/ocean bound will as wellnot only affects surface but atmosphereWeather MapsFront: boundary b/n two differing air massesCold: cold air replacing warmWarm: warm air replacing coldStationary: border b/n to different fronts, neither front strong enough to move the otherOccluded: cold front overtakes warm frontAtmospheric Temperature ProfileTemperature decrease as go higher up in atmosphereNot as close to surfaceAir is thinnerAir decreases to a point than warms up againTroposphere (colder as increase) MOVE AWAY FROM SURFACETropopause: point at which stop decreasingStratosphere (warmer as increase) OZONEStratopause: point at which stop increasingMesosphere (colder as decrease) LEAVE OZONEMesopause: point at which stop decreasingThermosphere (warmer as increase) SUNPressureInches of mercuryMultiply inches of mercury by 33.865 to convert to mbAs pressure drops the barometer is said to be “falling”Generally means severe/some sort of weather is comingIdeal Gas LawPressure X volume = constant X temperaturePressure = density X temperature X constantDensity= pressure/temperature X constantAtmospheric CompositionMajor nonpermanent gasNitrogenOxygenArgonVariable GasWater vaporCO2MethaneNitrous oxideOzoneCFCsCarbon dioxide cycleMore sources than sinksCO2 has a variety of natural and anthropogenic sourcesAs plants grow they absorb CO2 from the air (Levels of atmospheric CO2 decrease)MethaneMethane is lost mainly by chemical reactions in the atmosphereWater CycleTPW (total precipitable water)Difficult to say if there is a trend in atmospheric waterHeld pretty steady since the 1990sThe water cycle plays a major role in drving weather and climatePowered by solar energy, more sunlight=more evaportationClouds reflect incoming solar energy=cool surfaceCFCsChlorofluorocarbonNo natural sources of CFC’s represent a family of gasesChemically engineeredIncrease in levels since 1940  “Great Acceleration”Ozone deterriates1970s (US bans) decrease in CFC levels1990 Montreal Protocol  extreme decrease  ozone repairs itselfAerosolsVery tiny particles (measured in microns)Smog, smoke from fires, viruses, cloud particles, bacteria, human hair, beach sandAerosol Observations – satelliteCloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO)Can capture cloud formations, volcanic explosions, etc.April 17, 2012 CALIPSO captured image of the Eyjafjallajökull ash cloud after eruptionTemperature ScalesCelsiusCentigrade scaleMelting point of water is 0 degrees CBoiling point is 100 degrees CFahrenheit ScaleMelting point of water is 32 degrees FBoiling point is 212 degrees FKelvinSimilar to Celsius  Add 273.15 to Celsius to determine KelvinColdest temperature (ABSOLUTE ZERO) is 0 KNever goes negativeSpecific HeatThe specific heat of a substance is the amount of heat required to increase the temperature of 1 gram of the substance 1 degree CEnergy TransferCommon Energy TermsCalorieEnergy needed to raise the temperature of 1 gram of water 1 degree CDietary calorie = 1000 caloriesJoule0.2389 caloriesconversion purposesWattAmount of energy transferred over time1 watt= 1 joule/second100 watt light bulb = 100 J/s5 major energy transfer processesconductionrequires contact, energy transferred from molecule to moleculeAir is not a good conductorMetals are excellent conductorsMost important at Earth’s surfaceConvectionEnergy transferred by movement of fluids (in science air is considered a fluid)Surface energy transferred upward by convection“Hot air rises”AdvectionHorizontal movement of airLatent HeatingAmount of heat absorbed or released during a phase changeSolid, liquid, or gas describes phase of materialDoes not always mean change in temperatureWATER CYCLEEndothermic/exothermic reactionsIce  vapor : energy taken from environmentVapor  ice : energy released from environmentRadiative processesRadiative Heat  heating due to electromagnetic radiationDifferent from nuclear radiationLight Energy/Electromagnetic SpectrumWavelengthLength of one wave (lambda)AmplitudeHeight of the wave (1/2 distance from peak to trough)FrequencyThe number of times the wave peaks in 1 secondRadiation LawsStefan Boltzmann LawTotal amount of energy emitted by a blackbodyE=emitted radiatione=emissivity E=eoT4o=5.67X10-8T=temperature (K)EMISSIVITY tells us how well an object absorbs and reemits energy=1: everything gets absorbed and reemitted=0: nothing is absorbedWeins Displacement LawThe wavelength at which the energy spectrum reaches maximumWLmax um = 2900 (um K)/T (K)T(K) = 2900 (um K)/ WLmax (um)If you know the temperature you can find out the wavelength and vice versaElectromagnetic SpectrumThe energy from the sunpeaks at 0.5 umvisible portion of the spectrumshortwave radiationThe energy from the earthPeaks at 10 umInfrared (thermal) portion of the spectrumLongwave radiationExplains why we can see the sun and the earth (for us) doesn’t emit visible lightAlbedothe percentage of radiation that is reflected off of a surface100% means everything is reflectedsnow has an abledo of 90%Earth’s albedo=appx 30%Plays a vital role in determining the energy balance of the land/atmosphereSeasons and Surfaces affect on surface heatingSolar zenith angleThe angle between the sun and the point directly over headThe intensity of light reaching the surface decreases as the sun lowers in the skyAs SZA increases, INTENSITY decreasesWhy does it change?LatitudeHigher latitudes experience shorter days in winterColder/less solar energy hits directlyTilt of earth awayHigher latitudes experience longer days in summerWarmer/more solar energy hits directlyTilt of the earth towardsEquator experiences relativily constant temperature/climate year-roundRadiative ForcingAnnual Mean temperatureTemperature cycles30 year average surface air temperatureAir temperature dataDaily mean temperature determine two waysAverage 24 hourly measurementsAverage of max. and min. temperatures for the dayDaily temperature rangeDifference between the max and min temperaturesMonthly mean