GC 170 1st EditionExam # 3 Study Guide Midterm study guideContent: - 10 multiple choice Q’s (20 points total)- 14 short answer Q’s (10 points each, 140 total)- 2 short essays (20 points each, 40 total)- Total points: 200Short Essay Questions: - The Greenhouse effect, understanding the cartoon and effects of the Greenhouse Effect No atmosphereNo GE The earth would be freezing1. Incoming Solar Radiation2. Radiation absorbed at the surface (earth’s temperature increases)3. Earth emits longwave radiation (based on earth’s temperature)4. If there is no atmosphere, then all longwave radiation transmitted out to spaceNormal atmosphereGE 1. Sun emits shortwave radiation (Mostly UV, visible light, some IR) 2. Earth absorbs shortwave radiation (earth’s temperature increases) 3. Earth emits longwave radiation (Wien’s Law: which states that it is based on its temperature) 4. Greenhouse gases absorb outgoing longwave radiation5. Greenhouse gases re-emit the longwave radiation back towardsthe earth 6. Lower atmosphere is heatedIncreased CO2 levels Enhanced greenhouse effectHas to do with how much CO2 humans are putting into the air1. Sun emits shortwave radiation (Mostly UV, visible light, some IR)2. Earth absorbs shortwave radiation (earth’s temperature increases)3. Earth emits longwave radiation(Wien’s Law: based on its temperature)4. MORE greenhouse gases absorb outgoing longwave radiation 5. Increased Greenhouse gases emit MORE longwave radiation back towards the earth 6. earth becomes warmer (temperature increases)- The Keeling Curve, the history of the measurements, what it shows and why it is important for understanding an enhanced greenhouse effecto Scientists were wondering about CO2 levels in the atmosphereo Project to calculate levels of CO2 in the air started by Dave Keeling, in Pasadena, CA in 1958 Too much influence from the industry Project moved around the United States to find fluctuations in CO2 levels throughout the day - Except in the middle of the afternoon, everywhere, there were 310 ppm’so The project is now situated in an observatory on top of a tall mountain in Hawaii, Mauna Loa No industries No nearby cities Far from vegetation No inversion layerso Fluctuations - Late summer- CO2 stored in leaves (Low Points)- Winter- Leaves have decayed, CO2 in air (High Points)o This is important to global change because… More CO2 creates an enhanced Greenhouse effect- Warmer temperaturesShort Answer Questions & Multiple Choice (Organized in Lectures)Lecture 3: Electromagnetic spectrum and radiation-- Shorter Wavelengthso Higher frequencyo Higher energy- Longer wavelengthso Lower frequencyo Lower energy- The sun emits shortwave radiation (UV) – which is visible to infrared - The earth emits longwave radiation (100% IR)Lecture 4: Radiation Laws- Planck Function: Distribution of energyo Intensity of radiation to the wavelengths emitted by a blackbody (emits at ALL wavelengths) - Wien’s Law: o One wavelength where a blackbody emits a maximum amount of radiation: related to temperature The maximum radiation flux (peak) occurs at a wavelength that is inversely related to the temperatureo As the earth’s temperature warms, the peak (and whole curve) shifts to theleft- Stefan-Boltzmann Lawo Total energy emitted is proportional to the temperature of the bodyo Sensitive to temperature because it is proportional to the fourth powerLecture 5: Atmospheric Structure-o Ozone layer is located in the stratosphereo Greenhouse gases occur in the troposphere (as well as temperature) CO2 and H2O are the most common greenhouse gases (NH4 is also a greenhouse gas)o Line represents temperature  Starting from top Increasing (thermosphere) Decreasing (mesosphere) Increasing (stratosphere) Decreasing (troposphere)- Processes of Heat Transfero Convection: transfer of thermal energy within a fluid by means of movement or circulation in gases or liquids - example: clouds in the troposphere, heating water. Process of heat transfer upwards in the atmosphere Phase change: the transition between different states- Liquid, Solid, Gaso Radiation: the transfer of thermal energy by electromagnetic radiation. The only process that does not require movement of atoms or molecules to facilitate the transfer.o Conduction: transfer of thermal energy between or through objects by way of direct contact. Most effective in solids.Lecture 7: The greenhouse Gases- Greenhouse Gaseso Triatomic structure that allows them to absorb and re-emit longwave radiation: o Process causes vibration, bending and rotation of atomic bonds o Greenhouse gases do not react to incoming shortwave radiation (i.e., let visible light pass through)- Atmosphereo Incoming solar radiation passes through molecules o Outgoing longwave radiation also passes through these molecules (Do notreact to outgoing longwave)- Absorption Spectrum-o Incoming UV absorbed by ozone layer in the stratosphere o Visible light allowed to pass through to the earth surface o Longwave radiation absorbed and re-emitted back towards the earth surface o The atmospheric window: allows narrow band of longwave radiation to pass through the atmosphereLecture 8 & 9: The Energy Budget- Solar radiationo Reflected by clouds & atmosphere & surfaceo Absorbed by atmosphere & surface- Longwave radiationo Radiated upwards The surface  Greenhouse gases in the atmosphereo Radiated downwards Greenhouse gases in the atmosphere and clouds Lecture 10: Modern processesa. Atmospheric circulationi. Hadley Cell circulation1. Incoming solar radiation goes down towards earth 2. Heats up ocean and land 3. Warm air rises (convection and uplift)  through humid air and water vapor4. Convergence: Area of low pressure at the surface (surface winds move towards this area)5. Equator: Intertropical Convergence zone6. Divergence: Cool air sinks from up in the troposphere a. Surface winds flow away at the surface which creates high pressureb. At areas of high pressure, warm air diverges at the surfacei. Prevents condensation (cloud formation)ii. Environment becomes very dry (desert)7. Polar Front zonea. Zone of converging air from equator and polesi. Very cold and dense air ii. Air flows away from north poleiii. Warm air rises up  cool air sinks below warm air8. Jet Streama. Current of upper-level winds moving west to easti. Pushes storms across the polar front b. Caused by strong temperature and pressure gradient in upper