Answer to Question #169876 in Astronomy | Astrophysics for Lanna

Question

all questions please

a)   Determine the total power (from solar energy) at the top of the Earth’s atmosphere

b)   What power would be absorbed by the Earth’s surface in the absence of an atmosphere? Hint: Think about our albedo.

c)    What would the surface temperature be assuming it radiated into space all the energy it absorbed?

Answer 1

1. On average, 340 watts per square meter of solar energy arrives at the top of the atmosphere. Earth returns an equal amount of energy back to space by reflecting some incoming light and by radiating heat (thermal infrared energy).

2. If no energy is returned back to space, then all 340 watts will be absorbed by the Earth's surface

3. Without the effect of the atmosphere, the average surface temperature of the Earth would be between -18 and -23 ° C (despite the fact that in reality it is 14.8 ° C), and life, most likely, would not exist