Mid-term review 1

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Mid-term review 1
Chapter 1
1. Weather and Climate
Reading P4-6
Weather state of the atmosphere at a given time
and place. It is constantly changing.
Climate average weather conditions
Climate is what you expect, but weather is what
you actually get.
2. Four Spheres in the Earth System
Reading P12-P16
Geosphere, Atmosphere, Hydrosphere, Biosphere
3. Systems
A group of interacting parts (components) that
form a complex whole.
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Open System Energy and Matter can be exchanged
between systems Closed System Exchange of Matter
greatly restricted, but may allow exchange of
energy Isolated System No Energy or Matter can
be transferred in or out of the system
4. Feedback
Reading P397
Processes in one system influences processes in
another interconnected system by exchange of
matter and energy.
Positive Feedback Change in one system causes
similar change in the other system. Can cause
runaway instability. e.g., water vapor feedback,
ice cover feedback Negative Feedback A positive
change in one system causes a negative change in
the other. e.g., cloud cover feedback
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5. Composition of the Atmosphere
Reading P17-P24
Major components Nitrogen (N2), Oxygen (O2),
Argon (Ar), Carbon dioxide (CO2),
Minute trace gases water vapor (H2O),Methane
(CH4), Ozone (O3), Nitrous Oxide (N2O)
Variable components Water vapor, Aerosol, Ozone
Aerosol direct and indirect effect
Ozone depletion and ozone hole
6. Extent of the Atmosphere
Reading P24-P25
Pressure Force F acting on unit area due to the
weight of the atmosphere. Surface atmospheric
pressure 1000 hPa or 1000 mb
Temperature
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Thermal Structure of the Atmosphere
Reading P26-P30
Troposphere

• Averaged Surface temperature is 288.16K, or 15C.
• Decreases 6.5C per km up to 11 km (lapse rate).
• Nearly all weather happens in this layer.
• Height of the tropopause varies with latitude
  with an average of 10 km.

Inversion Negative lapse rate, temperature
increases with height.
Stratosphere
Temperature is constant in the lower part of the
layer, and then, increases with height due to O3
absorption of solar UV. 99 of the atmosphere
is below the stratopause.
Mesosphere
Temperature decreases with height in this layer
Thermosphere
Temperature increases greatly because air absorbs
sunlight.
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Chapter 2
Reading P36-P42
1. Sun-Earth relationship
Earths motion, Seasons, Earths orientation,
Solstices and Equinoxes
Reading P43-P44
2. Forms of energy
Kinetic energy
Potential energy
Heat
3. Mechanisms of Energy Transfer
Reading P44-P47
Conduction, convection, and radiation
4. Laws of blackbody radiation
Reading P47-P48
Stefan-Boltzman law, Wiens displacement law,
Planks law
6000K
300K
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5. Selective absorption and emission of
atmospheric gases
M
Electronic excitation
Photoionization
overlap
Almost all solar radiations shorter than
ultraviolet are used up in the upper layer for
photoionization, electronic excitation, and
molecule dissociation. Since most of solar energy
is in the visible band, they have nothing to do
with molecule vibration and rotation transition,
so solar radiation can reach Earth's surface
almost without any attenuation. On the other
hand, terrestrial radiation in the infrared band,
which is involved with atmospheric molecule
vibration and rotation transitions, can be
absorbed by the atmosphere to cause greenhouse
effect.
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Reading P54-P55
6. Greenhouse Effect
Shortwave solar radiation is nearly transparent
to the atmosphere, but longwave terrestrial
radiation is trapped by greenhouse gases, causing
the increase of surface temperature.
7. Atmospheric window
Reading P53-P54
Highly un-reactive greenhouse gases containing
bonds of fluorine-carbon or fluorine-sulfur,
such as Perfluorocarbons (CF4, C2F6, C3F8) and
Sulfur Hexafluoride (SF6). These trace gases have
strong absorption lines right in the atmospheric
window. Clouds can also absorb longwave
radiation in the atmospheric window.
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8. Solar constant incoming solar radiation per
unit area at the top of the atmosphere
9. Radiative Equilibrium, Radiative-covection
Equilibrium
Reading P56
10. Heat Budget of Earths Atmosphere
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11. Latitudinal energy balance
12. Transport by atmospheric motion and ocean
currents
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Chapter 3
1. Air Temperature
Isotherms
Temperature gradient
Reading P66-P67
2. Controls of Temperature
Reading P68-P75
Differential heating of land and water Ocean
currents Altitude Geographic position Cloud
cover and albedo
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3. Daily Cycles of Air Tmperature (diurnal)
Reading P81-P82
What controls the diurnal variation?
4. Heat island effect
Reading P84-P85

• Buildings absorb and store more solar radiation.
• City surface results in reduction of evaporation.
• Heat sources from heating system,
  air-conditioning, and industry.
• Air pollution

5. Temperature measurement
Reading P86-P90
Maximum and minimum temperature
Instrument shelters
6. Heat stress and wind chill
Reading P91-P94
Heat stress is caused by high temperature and
high humidity.
Wind chill is the cooling power of moving air.
7. Temperature Scale
Reading P89-P90
Tt273
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Chapter 4
1. Phase change and latent heat
Reading P98-P102
2. Equation of state, gas law of dry air
3. Measuring water vapor in the air
Water vapor pressure
Mixing ratio, r
Reading P103
Moist virtual effect
Virtual temperature
4. Saturation
Reading P104-P105
Saturated water vapor pressure, EE(T)
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5. Relative humidity, h
Reading P106-P108
Reading P109-P111
6. Dew-point
7. Internal energy U
Energy associated with the random, disordered
motion of molecules. UU(T)
8. Hydrostatic balance the balance between
upward pressure gradient force and downward
gravitational force.
9. First law of thermodynamics in the atmosphere
The change in internal energy of a system is
equal to the heat added to the system minus the
work done by the system.
10. Dry adiabatic process
Reading P112-P116
Lifting mechanisms
11. Adiabatic lapse rate
Lapse rate of ambient environment
12. Lifting condensation level (LCL)