chapter 2

Question 1

Solar radiation emitted from sun which passes through the atmosphere and is reflected in

Answer 1

varying degrees by Earth’s surface and atmosphere and is detectable only during daylight.

Question 2

Sun’s visible surface has temperature

Answer 2

6000K

Question 3

99% of sun’s radiation fall between

Answer 3

0.2 - 5.6um (in the range of UV, Visible and IR), atmosphere quite transparent to incoming solar radiation

Question 4

the sun emits many forms of electromagnetic radiation in varying quantities. as shown in the diagram, about

Answer 4

43 percent of the total radiant energy emitted from the sun is in the visible parts of the spectrum.

the bulk of the remainder lies in the near infrared (49 percent) and UV section (7 percent).

less than 1 percent of solar radiation is emitted as x-ray, gamma waves, radio waves

Question 5

maximum radiation occurs

Answer 5

0.48um (in the visible range)

Question 6

about 1/2 of solar radiation passes through the atmosphere and absorbed in

Answer 6

varying degrees by surface

Question 7

terrestrial radiation is emitted from

Answer 7

the Earth and atmosphere

Question 8

terrestrial radiation is emitted from the Earth and atmosphere
 detectable both

Answer 8

day and night Earth’s ambient temperature -300K

Question 9

detectable both day and night Earth’s ambient temperature -300K
 Earth radiates ………………. times less than the sun

Answer 9

160,000 times

Question 10

essentially all energy is radiated at

Answer 10

(invisible) thermal infrared wavelengths between 4-25um

Question 11

maximum emission occurs at

Answer 11

97 um

Question 12

Wavelengths covering most of Earth’s energy output are several times …………. than those covering most of the solar output

Answer 12

longer

Question 13

Wavelengths covering most of Earth’s energy output are several times longer
than those covering most of the solar output. Therefore, refer to following
as:

Answer 13

terrestrial radiation - longwave radiation
solar radiation - shortwave radiation

Question 14

Practically all of the energy that reaches the earth comes from the sun.
Intercepted first by the atmosphere, a small part is directly absorbed,
particularly by certain gases such as

Answer 14

ozone and water vapor.

Question 15

Practically all of the energy that reaches the earth comes from the sun. Intercepted first by the atmosphere, a small part is directly absorbed, particularly by certain gases such as ozone and water vapor. Some energy is

Answer 15

reflected back to space by clouds and the earth’s surface.

Question 16

Practically all of the energy that reaches the earth comes from the sun. Intercepted first by the atmosphere, a small part is directly absorbed, particularly by certain gases such as ozone and water vapor. Some energy is reflected back to space by clouds and the earth’s surface. only ………. of the solar radiation is absorbed by the earth’s surface

Answer 16

51%

Question 17

Energy is transferred between the earth’s surface and the atmosphere in a variety of ways, including

Answer 17

• radiation 60%
• conduction (small)
• convection (15-20%)

Question 18

The electromagnetic spectrum is the

Answer 18

distribution of electromagnetic radiation according to energy (according to frequency or wavelength).

Question 19

the main band of EM are

Answer 19

IR

visible

UV

Question 20

Less than 1% of solar radiation is emitted as

Answer 20

x-rays, gamma waves, and radio waves

Question 21

The narrow visible part of the electromagnetic spectrum corresponds to the wavelengths near the

Answer 21

maximum intensity of the Sun radiation

Question 22

White light may be separated into its spectral colors

Answer 22

(red, orange, yellow, green, blue, indigo and violet or “ROY G. BIV”) by dispersion in a prism.

Question 23

Ultra violet

The region just below the

Answer 23

visible in wavelength is called the near ultraviolet

Question 24

The region just below the visible in wavelength is called the near
ultraviolet. It is absorbed very strongly by

Answer 24

most solid substances, and in the atmosphere absorbed by ozone.

Question 25

The region just below the visible in wavelength is called the near ultraviolet. It is absorbed very strongly by most solid substances, and in the atmosphere absorbed by ozone. The tissue effects of ultraviolet include

Answer 25

sunburn, but can have some therapeutic effects as well.

Question 26

The region just below the visible in wavelength is called the near
ultraviolet. It is absorbed very strongly by most solid substances, and in the
atmosphere absorbed by ozone. The tissue effects of ultraviolet include
sunburn, but can have some therapeutic effects as well. The sun is a strong
source of

Answer 26

ultraviolet radiation

Question 27

The tissue effects of ultraviolet include
sunburn, but can have some therapeutic effects as well. The sun is a strong
source of ultraviolet radiation, but atmospheric absorption eliminates

Answer 27

most of the shorter wavelengths.

Question 28

radiation balance figure

Question 29

IR

Answer 29

infrared light is the part of the EM spectrum that is invisible to human eye, but people still feel it as heat.

everything with a temperature above about 5 degrees kelvin emits IR radiation. the sun gives pff half of its total energy as IR, and much of its visible light is absorbed and re-emitted as IR

Question 30

Viewed from above, the Earth makes a complete …………………….. rotation (spins on its axis) once in each 24-hour period.

Answer 30

counterclockwise

Question 31

Viewed from above, the Earth makes a complete counterclockwise rotation (spins on its axis) once in each 24-hour period. This is why the Sun appears to rise in the east and set in the west. The Earth also revolves counterclockwise around the Sun once every

Answer 31

365 1/4 days

Question 32

The Earth’s axis is not oriented vertically, but is tilted by

Answer 32

23.5 degrees

Question 33

The Earth’s axis is not oriented vertically, but is tilted by 23.5 degrees.
The north end of the axis is always pointed toward the

Answer 33

North Star

Question 34

The Earth’s axis is not oriented vertically, but is tilted by 23.5 degrees.
The north end of the axis is always pointed toward the North Star as the
Earth revolves around the sun. This tilt, combined with its revolution around
the Sun, causes

Answer 34

seasonal change

Question 35

If the axis was not tilted, our year-round climate would be

Answer 35

rather boring and many places on Earth wouldn’t receive much light.

Question 36

During our summer

Answer 36

the Northern Hemisphere leans toward the Sun in its revolution, there are more daylight hours, and the Sun’s angle is more perpendicular to us than at other times of year. The longer days and more concentrated sunlight result in more heating. (Shadows are shorter in the summer because the sun strikes Earth more directly).

Question 37

During winter

Answer 37

the Northern Hemisphere leans away from the Sun, there are fewer daylight hours, and the Sun hits us at an angle; this makes it appear lower in the sky. There is less heating because the angled Sun’s rays are “spread out” rather than direct. (Shadows are longer because of the low er angle of the Sun).

Question 38

During winter, the Northern Hemisphere leans away from the Sun, there are
fewer daylight hours, and the Sun hits us at an angle; this makes it appear
lower in the sky. There is less heating because the angled Sun’s rays are
“spread out” rather than direct. (Shadows are longer because of the low er
angle of the Sun).
In equatorial regions, the length of days and the directness of sunlight

Answer 38

don’t change as much. The further you get from the equator, the more dramatic the seasonal changes.

Question 39

During the spring and fall

Answer 39

the Earth leans neither toward nor away from the Sun; daylight and nighttime hours are more equal and temperatures are moderate. (The shadow of an object is similar during these seasons)

Question 40

Solstice refers to

Answer 40

the two times each year when the Sun’s strongest rays are furthest from the equator (north of it during our summer solstice and south during the winter). For the northern hemisphere, summer solstice

occurs around June 21st; we have the maximum number of daylight hours at that time. Winter solstice is around December 21st when we have the fewest daylight hours

Question 41

Equinox

Answer 41

refers to the two times each year when the Sun’s strongest rays are directly hitting the equator. Everywhere on Earth has 12 hours of daylight on the spring and fall equinoxes. In the northern hemisphere, spring equinox occurs around March 21st and autumnal equinox around September 23^d