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1.Composition of the present atmosphere and its evolution The first two major composition of the present atmosphere: ATOC 4720 class 42: Final review : 75.51% by mass; : 23.14% by mass;
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Evolution: The earth formed first, and its present atmosphere are believed to be evolved from the volatile substance from volcanic eruption. Major composition of the raw atmosphere due to volcanic eruption: 85%, and 10% light
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2. The distribution of atmospheric pressure and density : 7-8 km; scale height; Where
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3. The fair weather elecric field and charged particles + + + + + + + + + - - - - - - - - - - - - - Charged Particles: important for lightening, reflection of radio waves, fair weather electric field, etc
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4. Temperature distribution with height
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5. Gas laws For a unit mass dry air: For unit mass of moist air: Where Virtual temperature
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6. The hydrostatic equation Large scale atmospheric motions satisfy hydrostatic balance. Balance between the upward PGF and the downward gravitational Force. PGF Gravity
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7. The geopotential and geopotential height : the work that must be done against the earht’s Gravitational field in order to raise a mass of 1kg From sea level to that point. J/kg. Geopotential height:
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8. The hypsometric equation Warm air: thicker Cold air: thinner;
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9. The first law of thermodynamics Applies for both diabetic and adiabatic processes. Diabetic: heat absorbed by a substance is used either to increase its internal energy or used to do external work. Adiabatic: dq=0. [1] Adiabatic expansion; [2] Adiabetic compression;
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10. Lifting condensation level (LCL) The lifting condensation level is defined as the level to which a parcel of moist air can be lifted adiabatically before it becomes saturated with respect to a plane surface of water. LCL -- well defined cloud base.
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11. Static stability and level of free convection Height Temperature LCL x Level of free convection Conditionally unstable;
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: unstable; : stable; T1 T2 T2e T1=T1e; then T2>T2e Convectively unstable; T inversion layer;
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12. Atmospheric aerosols Effects on cloud and precipitation: CCN; Should know why. Homogeneous nucleation is difficult to grow big; Atmoshperic electricity, radiation, chemistry.
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13. Hurricanes Dynamics: CISK; Air/sea interaction; Thermally direct Circulation: Available Potential Energy (PE) Is converted to Kinetic energy (KE). Maintenance: warm Core maintenance-- PE--KE;
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14. Radiation Wien displacement law: Stefan-Boltzmann law: Kirchhoff’s law:
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15. The global energy balance Top: 100% in 30% reflection 38%+26% atm emits; 6% IR emits Earth; Atm: 16%+3% SW abs; 15% IR abs; 7% abs sensible; 23% abs latent; 38% emits molecules; 26% emits clouds; Surface: 51% in; 23% latent; 7% sensible; 21% IR;
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16. Photoionization, photodissociation of oxygen, and fromation of ozone layer Upper thermosphere, photoionization of molecules and atoms Produces ionosphere, absorbs solar radiation: Photodissociation above 100km: Ozone is not formed in this high level however; mean free path Large, 3 body collision chance is small.
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20-60km: O is trace but important for ozone formation. Three body clission chance is large because mean free Path is small. Then, Reduce UV, Ozone layer protects the earth plants etc.
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