Lecture5 sep18-bb
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- 4. Warm Cold
- 5. Warm Cold
- 6. inversion layer, stable? Q: Why does the temperature increase with height in the stratosphere? contains ozone layer peak concentrations are at about 20-30 km Ozone absorbs ultraviolet radiation (UV) The ozone then reemits this energy in the form of heat into the stratosphere, warming it up in the mid-upper parts of the layer 97% of atmospheric ozone is in the stratosphere Ozone maximum
- 7. Bounded by the stratopause from below and the mesopause from above 99.9 % of air is below this level
- 8. The layer above the mesosphere Temperature increases with height
- 10. NYC daily Weather Temperature dew point temperature Relative humidity Wind Rain Weather Elements
- 11. Climate is the long-term average of weather “Climate is what you expect, weather is what you get.” – Robert Heinlein
- 12. Is Weather or Climate ? Ice Age? Climate Today’s Temperature in NYC? Weather Tornado? Weather Winter temperature? Climate Annual variability of precipitation in NYC? Climate
- 13. Climate change usually refers to temperature change
- 14. Temperature
- 15. Energy is defined as the ability to do work = 1 mv 2 m m ass v velo city 2 kinetic energy is the energy of motion kinetic energy is large when velocity is large
- 16. m = mass 1 e1 1 2 i 2 2 1 1 mv 1 e2 2 m2v 2 2 1 ei 2 v = velocity 2 m i vi e 1 mv 2 2 kin etic en erg y 1 k BT 1 2 2 1 1 mv 1 m2v 2 mv 2 2 2 kB is the Boltzmann constant 2 2 1 2 m3v 2 3 ... 1 2 N miv 2 i ... 1 2 2 m N vN
- 17. Temperature and Heat Absolute temperature is proportional to the average kinetic energy of its constitute atoms and molecules Heat energy exchange from one object to another What is difference between temperature and heat?
- 18. Object 1 Object 2 Heat = an exchange of kinetic energy Equilibrium = Both objects have the same temperature
- 19. Heat Latent Heat energy required for a substance (i. e. water) to change from one state to another at constant temperature Sensible Heat heat added or taken from a gas, liquid or solid that causes a change in temperature
- 20. Need energy Need energy release energy release energy Lecture 4- 20
- 21. scale melting point of ice boiling point of water Fahrenheit (oF) 32 212 Celsius (oC) 0 100 Kelvin (K) 273 373 • Relative size of a degree F vs. a degree C--compare the number of degrees between freezing and boiling: 100oC = 180oF 1oC = 1.8oF
- 22. Temperature Scales: Fahrenheit and Celsius (oC x 1.8) + 32 = oF (oF - 32) / 1.8 = oC
- 23. Why Kelvin temperature is also called absolute temperature? Third Law of Thermodynamics It is impossible to cool a body to absolute zero by any finite process. Although one can approach absolute zero as closely as one desires, one cannot actually reach this limit.
- 24. There are three ways of heat transfer in the atmosphere
- 25. Heat Transfer Conduction from warm to cold from molecular motions Air is a poor conductor of heat Basically insignificant
- 26. Convection transfer energy through mass movement of a substance Q: what are examples of atmospheric convection? consider a hot parcel of air near the ground what is the parcel going to do? Thermals It’s going to rise, why? a thermal is formed Q: By which mechanism is the heat transferred from ground to the air adjacent to the ground? Lecture 4- 26