1. Radiation balance Any object in the Universe which has a temperature above the temperature "absolute zero" (-459.67 degrees Fahrenheit or -273.15 degrees Celsius or zero degrees Kelvin) has radiation.

2. Explain the differences between short and longwave radiation and how they heat the Earth Define and describe radiation cooling Define and describe counter-radiation warming Explain why the naturally occurring concentrations of greenhouse gases in our atmosphere are necessary Explain the concept of a stable state and a dynamic equilibrium and how it relates to the radiation budget and temperature of the atmosphere Explain albedo and contrast a dark and a light surface in terms of their reflectivity and absorption of insolation Trace the path of 100 units of incoming solar radiation Give an example of positive feedback effects associate with increased global warming and decreased ice cover in the Arctic Explain why the coldest temperatures occur on clear nights Differentiate between heat and temperature Differentiate between sensible and latent heat Define and describe convection currents Explain how evaporation and condensation of water can transport heat Given a phase change for water, state if heat or energy is absorbed or released into the environment Define evaporative cooling and condensation warning List and explain factors that determine the heat energy balance and temperature Define/describe advection

3. Radiation All objects emit radiation Radiation can pass through objects unaffected, travel thru a vacuum, or be absorbed and reemitted.

4. Radiation The sun emits radiation composed of high energy infrared radiation, visible light, and ultraviolet radiation collectively known as shortwave radiation (SW) The earth emits radiation composed of lower energy infrared radiation collectively known as longwave radiation (LW)

5. SunEarth Sun: shortwave radiation Earth: longwave radiation

8. How does solar radiation heat Earth? Through counter-radiation warming, in which the atmosphere is heated from below by longwave radiation. Analogy: parked car with the windows rolled up

9. Radiation cooling When are our nights coldest, when it is cloudy or when it is clear? Why is the desert so cold at night?

10. Nighttime longwave radiation emission, April

12. Smudge Pots Fruit growers will sometimes use smudge pots to try to protect their crops from a possible killing frost, particularly on clear, cold nights. A smudge pot is a portable heater/burner which produces thick heavy smoke. Fruit growers place a number of these around the orchard in the evening to prevent the crop from freezing at night. Do smudge pots actually work? Why? A.Yes. They work simply by heating the air in the orchard to keep it above freezing. B.No. They don't work. They can not supply enough heat to keep the orchard from freezing. C.Yes. They work by producing a heavy smoke layer over the orchard which prevents heat loss by radiation to the night sky D.I think someone should notify the Pollution Control Agency. http://www.aqmd.gov/news1/Archives/History/smudge.html

13. Path of incoming solar radiation (100 units) Only 50% of insolation absorbed at surface 20% of insolation absorbed by atm 30% of insolation lost to space

14. Radiation balance SW in and LW out to maintain temperature at steady state (water level does not fluctuate) Dynamic equilibrium: changes in the amount of incoming or outgoing radiation (water level has up and down trends) How would increased atmospheric concentrations of these substances alter the water level of the bucket (temperature)?: Aerosol air pollution? Carbon dioxide?

15. Radiation budgets

16. Net radiation

17. Which plot is our summer? Our winter? Annual radiation balance?

19. Albedo: a measure of how well a surface reflects insolation.

21. Reflected shortwave radiation, May

22. Albedo measures (% reflected) Fresh snow 80-95 % Forests 10-20 % Asphalt 5 to 10 % Water bodies 10 to 60 % (depending on sun angle) Light roof 35 to 50 % Dark roof 8 to 18 %

23. Example of albedo-related feedbacks

24. Heat Transfer 1.Energy is not created or destroyed but converted from one form to another 2.Radiation is converted to heat energy The first commercial microwaves (1947) were actually gigantic and enormously expensive, standing 5 1/2 feet tall, weighing over 750 pounds, and costing about $5000 each. They had to be water-cooled, so plumbing installations were also required.

25. Heat versus temperature 3.Heat is the measure of the total amount of motion of molecules. Temperature is a measure of the average speed of the molecules. A unit volume of ocean has more heat but a lower temperature than the same volume air in the thermosphere (low heat but high temperature).

26. 4.Heat energy flows from warm to cold 5.Two kinds of heat: sensible and latent 6.Sensible heat can be sensed and measured. 7.Sensible heat can be transferred three ways: radiation, conduction, convection Radiation Conduction Convection

27. But what is latent heat?

28. 8.Latent heat is heat that is tied up in the phase changes of water Remember: Evaporation cools the environment; condensation warms it.

30. Latent heat flux Latent heat flux is the amount of energy moving from the surface to the air due to evaporation.

31. Latent heat fluxflux Latent heat flux is the amount of energy moving from the surface to the air due to evaporation. Why is latent heat flux less in the cities? What are the implications for temperature?

32. 9.Temperature at any one point is determined by the net balance between net radiation, sensible heat content, latent heat transfer, advective heat transport (wind-driven), and moisture availability What determines the temp on the roof of this car?

33. 10.Heat is continually redistributed in the Earth’s atmosphere via evaporation and condensation.

34. 11. Ocean currents also redistribute heat