If you’re really low on time, please finish 4th only will you give your like any
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If you’re really low on time, please finish 4th only will you give your like anyway T-Mobile 14:39 45%. HW 2.docx Part1: Energy Balance and the Greenhouse Effect Early in the Earth's history the Sun was only approximately 70% as bright as it is now. We call this the Faint Young Sun. This made for a solar constant, S = 952 W/m Question 1: What was the Energy per area during this period? Assume the Earth has the same albedo as it does now. Hint: there is an equation in your book to calculate this. We also went through the process in lecture Question 2: How much energy would the Earth have to radiate in order to be in energy balance? Question 3: What temperature would the Earth have to be in order to emit that much energy? Assume there is no atmosphere. Question 4: Now we will assume this early Earth has an atmosphere that absorbs infrared radiation, causing a greenhouse effect. Using the same method shown in the book and demonstrated in class, fill in the blanks (or list a-g below) in the following diagram. Hint: you've already calculated some of these. The amophre raiaingatK Open With PrintExplanation / Answer
3. Using the energy balance equation,
S/4(1-) = Ts4
Considering = 0.3, = 5.67 *10-8 Wm-2K4
(952/4)(1-0.3) = 5.67 *10-8 . Ts4
Ts = 232.8 K
Assuming there is no atmosphere, temperature must be 232.8 K in order to emit 166.6 Wm-2
4. If atmosphere is present, then equation becomes
2 Te4 = Ts4
Te is effective temperature calculated without the effect of greenhouse gases. Ts is the average surface temperature in the presence of atmospheric greenhouse gases.
Ts = ((2 * 166.6)/ )0.25 = 276.8 K
a. Incoming solar radiation S/4 = 238 Wm-2
b. Outgoing atmospheric radiation towards space is 166.6 Wm-2
c. Atmosphere radiating at 333.2 Wm-2 (ans. b+d)
d. Outgoing atmospheric radiation towards surface is 166.6 Wm-2
e. Solar Radiation reaching the surface, i.e. S/4(1-) = 166.6 Wm-2
f. Outgoing radiation from surface = 333.2 Wm-2 because 2 Te4 = Ts4
g. Surface temperature Ts = 276.8 K