1. The diagram below shows numerical estimates of annual energy fluxes on Earth, in units of...

 

 

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1. The diagram below shows numerical estimates of annual energy fluxes on Earth, in units of 108 terawatt-hours (TWh), where 1 TW = 10 W. For example, the "15.1" solar input number at the top means that a total solar energy input of 15.1 x 108 TWh strikes the top of the Earth's atmosphere in one year, of which 0.024 x 108 TWh is used in photosynthesis. Sun 15.1 3.9 (Reflected by atmosphere) 3.6 (Heating of atmosphere) Photosynthesis 0.024 (Reflected by surface) 4.9 (Heating & Evap. in oceans) HO Water evaporation 0.6 3.5 Wind.03 2.1 (Heating of land) Burial of www plant material <0.01% Geothermal heat 0.0028 Other Fossil sources 0.0002/yr 0.0010/yr Stocks of fuels fossil fuels 0.15 Human primary energy use 0.0012/yr HO Ocean Ocean 0.0003 Tides & waves thermal energy 0.033 Please answer the following questions, showing all your calculations in detail. (a) Convert the solar input shown in the diagram to units of Joules. How many Joules per second of solar energy are incident on the Earth? (b) Show that the value of Joules/sec you just calculated in (a) is equivalent to the solar insolation constant of 1350 W/m at the top of the atmosphere. Be sure to use the proper area in your calculation. (c) Use the Stefan-Boltzmann equation to calculate the total IR radiation shining from the Earth's surface in units of W/m. The average surface temperature of Earth is 15C. (d) Compare the numerical values you calculated in parts (b) and (c). They should not be the same. How do you account for this? Now use the diagram to answer the questions below. Show all your calculations in detail. (e) What percentage of the total annual energy flux on Earth is completely independent of the Sun? (f) What fraction of the annual solar energy input do humans make use of? (g) What is the overall albedo of the Earth? (h) At the present rate of consumption, how long will fossil fuel stocks last? 1. The diagram below shows numerical estimates of annual energy fluxes on Earth, in units of 108 terawatt-hours (TWh), where 1 TW = 10 W. For example, the "15.1" solar input number at the top means that a total solar energy input of 15.1 x 108 TWh strikes the top of the Earth's atmosphere in one year, of which 0.024 x 108 TWh is used in photosynthesis. Sun 15.1 3.9 (Reflected by atmosphere) 3.6 (Heating of atmosphere) Photosynthesis 0.024 (Reflected by surface) 4.9 (Heating & Evap. in oceans) HO Water evaporation 0.6 3.5 Wind.03 2.1 (Heating of land) Burial of www plant material <0.01% Geothermal heat 0.0028 Other Fossil sources 0.0002/yr 0.0010/yr Stocks of fuels fossil fuels 0.15 Human primary energy use 0.0012/yr HO Ocean Ocean 0.0003 Tides & waves thermal energy 0.033 Please answer the following questions, showing all your calculations in detail. (a) Convert the solar input shown in the diagram to units of Joules. How many Joules per second of solar energy are incident on the Earth? (b) Show that the value of Joules/sec you just calculated in (a) is equivalent to the solar insolation constant of 1350 W/m at the top of the atmosphere. Be sure to use the proper area in your calculation. (c) Use the Stefan-Boltzmann equation to calculate the total IR radiation shining from the Earth's surface in units of W/m. The average surface temperature of Earth is 15C. (d) Compare the numerical values you calculated in parts (b) and (c). They should not be the same. How do you account for this? Now use the diagram to answer the questions below. Show all your calculations in detail. (e) What percentage of the total annual energy flux on Earth is completely independent of the Sun? (f) What fraction of the annual solar energy input do humans make use of? (g) What is the overall albedo of the Earth? (h) At the present rate of consumption, how long will fossil fuel stocks last?

Answer rating: 100% (QA)

a To convert the solar input shown in the diagram to units of Joules we need to multiply the values by the appropriate conversion factors Given 1 TW 1010 W and 1 TWh 1012 Wh Solar input 151 x 10 TWh T... View the full answer