Chapter 9

Question 1

Which photon carries the most energy (waves spectrum)
Which photon carries the most energy — infrared, visible,
or ultraviolet?

Answer 1

Ultraviolet (Longer wave length, shorter frequency, lower energy)

Question 2

What processes contribute to the earth’s albedo being 30 percent?

Answer 2

A:When sunlight directly hits Earth’s surface, 51% will be absorbed by the surface. 19% will be absorbed by the atmosphere and clouds. The rest is reflected from the earth’s surface, clouds and scattered by the atmosphere, back into space which results in the albedo of 30%.

Question 3

In the Northern Hemisphere (US and China), why are summers warmer than winters, even though the earth is actually closer to the sun in January?

Answer 3

Earth should experience warmer weather in January and colder weather in July, due to the Sun being closer to Earth in January (147mil Km)than in July(152mil Km).
However, in the Northern Hemisphere, it is winter in January and summer in July. This shows that the solar proximity is not the main factor for the seasonal temperature of a region.

Factor 1: The earth is tilted at 23.5 degrees, which causes the sun to be on the horizon during January and the sun to be overhead during June. This causes the sun to have to penetrate a thicker atmosphere during January as compared to June. Because of a thicker atmosphere, there will be more scattering and absorption of sunlight, resulting in less energy reaching earth’s surface. This results in a warmer summer in June.

Factor 2: In the Northern Hemisphere, there will be longer daylight hours in July. The longer daylight hours result in a longer time exposed to sunlight and causes more sunlight to reach the Earth’s surface.