ATOC 1060 1nd EditionBased on Chapter 11&12 Lecture 16 Outline of Last Lecture I. Earliest formsII. Evidence of Early Life Preserved in RocksIII. Evolution of Atmospheric Oxygen ConcentrationsOutline of Current Lecture I. Burying CarbonII. Carbon Cycle during Carboniferous PeriodIII. Faint Young Sun ParadoxSun was dimmer back thenIV. Snowball Earth long term climate change our planet was covered with glaciersCurrent LectureI. Burying CarbonWhen you are burying carbon what does it mean?- You are taking carbon out of the atmosphere - CO2 is made of Carbon - When you are burying carbon you are taking C02 out of the atmosphere - CO2 levels then decrease- Taking the CO2 and putting it into rocks- Stays out of the atmosphere for a long timeOrganic Carbon: coming from dead plantsInorganic Carbon: found in RocksIt’s important for the Long-term Inorganic Carbon Cycle-If you increase burial of inorganic carbon over millions of years - Atmospheric/Ocean CO2 levels decrease-If you increase burial of organic carbon over millions of years These notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.- Atmospheric/Ocean CO2 levels decrease- Atmospheric/Ocean Oxygen levels increase- Dead plants turn into fossil fuel rocksQuestion # 1Burial rates of organic carbon doubled what they are today during the carboniferous. What does that mean about the carboniferous period back then?a. It had more Oxygenb. It had less Carbon Dioxide c. It had more Carbon Dioxided. A & BII. Carbon Cycle during Carboniferous Period- Burial of plant Carbon (burying CO2)- Inorganic Rocks form from heavy carbon- There were tons of isotopically heavy rocks - That means there was lots of organic carbon burial- More O2 - Less CO2What happens to atmospheric 13C/12C when we burn carboniferous coal?- Plants prefer 12C- Atmospheric 13C/12C decreases when we burn old plants- CO2 increases due to fossil fuelsQuestion #2Which of the following helps maintain atmospheric oxygen content at its current level?a. Increase oxygen reduces organic carbon burialb. Increase oxygen increases organic carbon burialc. Increase oxygen reduces inorganic carbon buriald. Increase oxygen increases inorganic carbon burialIII. Faint Young Sun ParadoxSun was 30% dimmer when earth formed yet there was liquid waterThe solutions to the Faint Young Sun Paradox?- The greenhouse effect was higher Methane and CO2- Not water vapor which is closer to saturation and provides a positive feedback not a long term forcing- The Planet albedo was Not lower in the past- Geothermal Heat was NOT big enough to supply the required energyQuestion #3What kept earth above freezing when the sun was 30 percent less luminous 4 billion years ago?a. Lower albedo b. More atmospheric carbon dioxidec. Geothermal energyd. More atmospheric methane e. B Or DTo keep at today’s temperatures we need 100x present CO2 and Methane would have to be 1000ppmTo keep earth from freezing with no methane we need CO2 at 60x presentMethane- Stronger gas than CO2Mie Scattering: Scattering where light scattered by particles of the same size lead to orange atmosphereRayleigh Scattering: Scattering where light scattered by particles that are much smaller than light wavelength (sky is blue)- Methanogens like it hot so they produce methane- Methane makes it hot- Positive feedback loop- At low concentrations methane is a greenhouse effect “Anti-greenhouse effect”- At high Methane concentrations, polymerization results in organic haze- Both methane and haze absorb visible radiation - Re radiate infrared energy to space at a certain height-IV. Glacial/Snowball EarthThere were 6 major glaciation periods over Earths HistorySnowball Earth: There were glaciers in the tropics and the entire earth was frozenHow are glaciers preserved in the geologic record?Question # 4How did the earth escape to warmer conditions from a snowball earth State during the late Proterozone era?A. methane emissions from methanogens living in the ocean increasesB. carbon dioxide increases no sink from silicate C. positive ice albedo feedback and positive water vapor feed backD. all the above E. B and