7: Solar (Shortwave) Radiation

Question 1

Top down effect

1) Define
2) What is its affect?

Answer 1

1) Increased incoming UV radiation stimulates O3 formation

2) Slight warming of the stratosphere

Question 2

Bottom up effect

1) Define
2) What is the affect?

Answer 2

1) Increase in incoming short-wave radiation at surface at the subtropics
2) Increase in evaporation of moisture from the oceans

Question 3

Wavelength

1) Define
2) Denoted with

Answer 3

1) The distance between two peaks or troughs

2) Lambda

Question 4

Frequency

1) Define
2) Formula
3) Denoted by
4) In direct proportion to

Answer 4

1) The number of peaks or troughs passing at a given point
2) f = c/lambda
(where c = speed of light)
3) f
4) Energy

Question 5

Energy

1) Define
2) Formula
3) Denoted by
4) In direct proportion to

Answer 5

1) Energy is the ability of an object to do work
2) E= hc/lambda = hf
(where h is planck’s constant)
3) E
4) Frequency

Question 6

If wavelength is high what of

1) f
2) E

Answer 6

1) Short

2) Low

Question 7

If wavelength is low what of

1) f
2) E

Answer 7

1) High

2) High

Question 8

Electromagnetic Spectrum

From short to long wavelength

Answer 8

Gamma-rays 1 pictometer
X-ray 10-4 micometer
Ultraviolet 0.1 micrometer
Visible 0.4 - 0.7 micrometer
Infrared 1.0 micrometer
Microwaves 1 millimeter
Radio 1 meter
Long wave 1 kilometer

Question 9

Visible spectrum

Longest wavelength to smallest

Answer 9

Red 780-630 nm
Orange 630-590 nm
Yellow 590-570 nm
Green 570-500 nm
Blue 500-450 nm
Indigo 450-420 nm
Violet 420-390 nm

Question 10

Visible light 
Red (780-630 nm)
1) Lambda
2) f
3) E

Answer 10

1) Longest
2) Shortest
3) Lower

Question 11

Visible light 
Violet (420-390 nm)
1) Lambda
2) f
3) E

Answer 11

1) Shortest
2) Highest
3) Higher

Question 12

Blackbody

1) Define
2) Do they reflect
3) Does the perfect blackbody exist

Answer 12

1) Absorbs and emits all wavelengths of electromagnetic radiation
2) NO
3) No

Question 12

Blackbody

1) Define
2) Do they reflect
3) Does the perfect blackbody exist
4) Two examples

Answer 12

1) Absorbs and emits all wavelengths of electromagnetic radiation
2) NO
3) No
4) Sun & stars

Question 13

Laws of blackbody radiation
Wien’s Law
1) Define
2) Formula

Answer 13

1) The wavelength of peak emission is inversely proportional to temperature
2) Lambda max = Constant/T
(where constant is Wien’s displacement)

Question 14

Laws of blackbody radiation
Stefan-Boltzmann Law
1) Define
2) Formula

Answer 14

1) The total energy emitted per unit surface of a blackbody area across all wavelengths is proportional to the 4th power of the body’s temperature
2) E* = Constant x T^4
(Where constant is Stefan-Boltzmann)

Question 15

Inverse Square Law

1) Define

Answer 15

1) The intensity of emitted radiation decreases by a factor which is the square of the distance

Question 16

Applying laws:
1. Sun is a lot hotter than earth
a) Emits more energy 
&
b) Emits shorter wavelengths
2. Earth is a lot cooler
a) Receives a small portion of sun's energy
&
b) Emits a longer wavelength

Answer 16

1. a) Stefan-Boltzmaan law
   b) Wein’s law
2. a) Inverse square law
   b) Wein’s law

Question 17

Energy absorbed (result)

Answer 17

Warming

Question 18

Energy emitted (result)

Answer 18

Cooling

Question 19

Why is the sky blue (day)

1) Define
2) Why?

Answer 19

Dust particles in the atmosphere are roughly the same size as the wavelength of blue light
Blue light has shorter wavelength so it gets scattered more (so you see more blue)

Question 20

Why is the sky blue? (evening & morning)

Answer 20

Shortwave radiation from the sun travels more though space

Now red light get scattered

Question 21

Why is the sky blue?

How far does it go?

Answer 21

Extends to only 30 km, as most of the dust particles are close to the surface

Question 22

Albedo

1) Define
2) Albedo of 1
3) Albedo of 0
4) What determines albedo

Answer 22

1) A measure of the reflectivity of the surface of a substance
2) All radiation reflected, lower temperature
3) Everything absorbed, temperature increases
4) By the colour of the surface

Question 23

Albedo (Darker colour)

1) Albedo
2) Absorption
3) Temperature

Answer 23

1) Low
2) High
3) High

Question 24

Albedo (Light colour)

1) Albedo
2) Relfection
3) Temperature

Answer 24

1) High
2) High
3) Low