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36 Cards in this Set
- Front
- Back
Define Stock |
Amount in a particular place and time. Eg. Amount of Co2 in the atmosphere is a stock |
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Define Flow |
Amount entering or leaving a stock at a particular time |
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Define equilibrium in terms of stocks and flows |
A system is in equilibrium when change over time equal 0. Or when rate(in)=rate(out)
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Amplifying feedback |
The changing stock causes to push the system in the direction of the initial disturbance. |
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Stabilizing feedback |
The changing stock causes to push the system in the opposite direction of the initial disturbance. |
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Define Kirchoff's Law |
Abs=, absorbtion equals emisivity, therefore the same about of energy absorbed will be emitted |
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What is the solar constant for Earth? What is its intensity? |
S=1360 W/m^2 (total energy emitted by the sun), Intensity=240 W/m^2 (solar energy per meter sq) |
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What is S a function of, what is I a function of? |
S is a function of distance away from the sun as well as the Earth's size, I is only a function of distance away from the sun. |
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What is the Greenhouse effect? |
A total difference in the outgoing radiation with the radiation being emitted from the ground. |
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What three factors is the surface temperature of the Earth determined by? |
number of layers in atmosphere, solar constant, albedo |
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Define forcing with feedback |
Forcing: a process that changes Earth's temperature but does not react to the changes in the temperature. Feedback: Responds to changes in Earth's temp and can change the temp in reaction. |
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What are the four major greenhouse gasses? |
H20, CO2, CH4, O3 |
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What is a greenhouse gas? |
Gasses that absorb and emit radiation in the long-wave |
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What is the atomic window+wavelengths? |
At 800-1000cm-1, satellites can get a clear view of the temperature of Earth's surface. i.e. there are no gases absorbing and emiting at this particular wavelength |
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Brightness temperature |
Temperature that a black body would need to be at to emit at a particular wavelength and flux. |
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Kinetic temperature |
Actual temperature of an object at emissivity of 1, the kinetic temperature will be equal to the brightness temp. |
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What happens to the emission of radiation by CO2 at 666 cm-1? |
CO2 absorbance spikes at 666cm-1 where it acts close to a black body. (Its transmittance) becomes close to 0. Since absorption is high, emitance will be high as well. |
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How is the Ozone spike at 990 cm-1 differennt than the CO2 spike. |
At 990cm-1 Ozone's transmittance increases by 70%, acting opposite of a black body. |
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What is the difference between Ozone in the stratosphere vs. troposphere? |
Ozone in the stratosphere absorbs high-energy ultra-violet light before the reach earth's surface. Ozone produced in the troposphere is usually from smog and causes health problems. |
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Describe water as a greenhouse gas |
Water is the most abundant greenhouse gas but does not drive global warming due to the ability to shed excess water in the atmosphere as rain. Amount of water vapour held depends on air temperature
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How does water impose an amplyfying feedback on earth's temperature? |
Water is held in the atmosphere and heats up atmosphere which in turn causes more water to be held in the atmosphere due to temp increase with further increases the temperature of the atmosphere. |
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Compare the half-life of ozone to nitrous oxide |
Ozone has an extremely quick half-life (one week) while Nitrous oxide produced by fertilizers has a half-life of about 100 years |
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Why is Carbon dioxide such an important greehouse gas? |
70% of anthropogenic emissions are CO2, CO2 does not oxidize or decay to form other molecules. |
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What is the ppm increase of carbon dioxide per year and how many Gt's are released into the atmosphere? |
2 ppm increase/year. 37 Gt carbon dioxide into atmosphere/ year and 10Gt carbon |
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How much of Co2 we release into the atmosphere stays within the atmosphere? |
About half |
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Band saturation |
When a certian wavelength has absorbed its maximum in CO2. However, increasing CO2 broadens the band with, allowing more Co2 to stay in the atmospher . |
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Which is radiative forcing log-based instread of linear? |
Due to band saturation, if we doubled the amount of Co2 in the atmosphere, we wouldn't double the Green house effect, eventually the amount of radiation added would get smaller and smaller IF the absorbitin band stayed constant which it does not |
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Hadley cells and advection |
Advection is the transport of heat by atmosphere or ocean. Hadley cells transport heat away from equator and towards poles preventing boiling at the equator. |
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Convection and lapse rate |
Lapse rate is the change in temperature with atmospheric height. Radiative lapse rate, is -16K/km, however with the presence of conduction transporting warm air upwards, lapse rate is closer to -6.5 or -8 K/km |
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Dry adiabatic lapse rate with moist adiabatic lapse rate |
Dry (-10 K/km): lapse rate of the atmosphere if it were completely dry without clouds. Moist (-6K/km): lapse is less caused by the condensation of water vapour which vibrates the water molecules which warms the surrounding air. |
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Low clouds with high clouds and their effect on climate. |
Low clouds: (below 2km) Highly reflective of visible light, high emisivity so absorb and emit long-wave radiation back to space and provide a cooling effect. High clouds: (above 6km) wispy and semi-transparent with low albedo, have crystals which absorb in the long-wave. Most greenhouse gases lie below and therefore they reemit gasses back to earth |
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Climate forcing |
Changes in flux out the top of earth's atmosphere |
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Climate sensitivity |
Depends on how much the temperature much change to accommodate changes in radiatative forcing. |
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What causes runaway feedback? |
If the value for climate sensitivity is negative |
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Plank feedback mechanism |
Stabilizing mechanism: if T increases, the outgoing radiation increases due to Plank's equation |
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Heat capacity and ocean heat content |
Heat capacity of climate is dominated by the ocean, the ocean can absorb much more heat (4x heat capactiy) as well as mixing causes heat to be distributed. |