Lecture 2

Question 1

weather

Answer 1

state of atmosphere at any given time and place

Question 2

climate

Answer 2

average state of climate over some given time interval

typically 30 year weather “normals”

Question 3

habitable zone

goldilock’s zone

Answer 3

• sweet spot that allows for evolution of complex life
• strongly controlled by distance from star

Question 4

stars

Answer 4

astral body that emits different wavelengths of EMR

Question 5

our sun emits…

Answer 5

mostly visible light (50%), some as infrared and longwave (40%), and the rest as UV or shortwave (10%)

Question 6

wavelengths

Answer 6

peak to peak

Question 7

frequency

Answer 7

how many waves in a given amount of time (waves/second)

Question 8

light is measured in ____, and what are they

Answer 8

photons
- tiny balls of energy
- smallest amount of discrete energy transported by an EM wave

Question 9

solar insolation

Answer 9

amount of energy passing through a given area over a given amount of time

Question 10

flux

Answer 10

amount of energy (# of photons) in an EM wave passing through a ceratin area/time

Question 11

solar flux is ____ at the poles because…

Answer 11

lower bc there is more area

Question 12

flux is dependent on …

Answer 12

distance from sun and angle of incidence

inverse square law means distance plays even bigger role

Question 13

eccentricity

Answer 13

elliptical orbit
- controls amount of solar insolation received
- 413000 years

Question 14

precession

Answer 14

wobble
- 24000 years

Question 15

obliquity

Answer 15

tilt
- 41000

Question 16

blackbody

Answer 16

ideal absorber and emitter in all wavelengths
- 100% efficiency
- doesn’t actually exist
- but most objects behave similarly

energy in = energy out

Question 17

Planck’s Law

Answer 17

relationship between intensity of radiation flux from a blackbody and its wavelength or frequency

Question 18

Wiens law

Answer 18

states rad flux from a blackbody reaches its peak at a max wavelength inverse to its absolute temp

the hotter the object, the shorter the wavelength

Question 19

what explains why the sun is yellow

Answer 19

Wien’s Law

Question 20

stefan-boltzman law

Answer 20

energy flux emitted by a bb is proportional to abs temp ^4

the hotter it is, 4x more flux

Question 21

first law of thermodynamics

Answer 21

law of conservation of energy
- when in equilibrium, earth is emitting to space the same amount it is absorbing from sun

Question 22

emissivity

Answer 22

thermal radiation emitted from a body’s surface vs the radiation emitted from an ideal blackbody surface at the same temperature

0-1, 1 = perfect emission, perfect blackbody

Question 23

Earth’s energy budget controlled by …

Answer 23

incoming/outgoing radiance
- temp of and distance from sun/
- radiated energy and earth’s albedo

Question 24

energy emitted equation

Answer 24

stefan-boltzman law and area of a sphere

Question 25

energy absorbed equation

Answer 25

energy intercepted - energy reflected area of a circle and solar constant and 1-albedo

Question 26

important difference between energy absorbed and emitted equations

Answer 26

one uses area of a circle one uses area of a sphere ## Footnote all of earth emits at once, but only half receives sun at once

Question 27

cause of discrepancy between what earth temp should be and what it is

Answer 27

greenhouse gases :) ## Footnote the atmosphere

Question 28

surface temp controlled by

Answer 28

○ Solar constant ○ Number of layers in the atmosphere ○ The albedo

Question 29

One layer atmosphere

Answer 29

○ Transparent to incoming shortwave ○ Opaque to outgoing infrared ○ Behaves like a blackbody (emits what it absorbs) ○ Energy outwards goes to space and energy down is re-absorbed - Calculation is too hot

Question 30

N layer model

Answer 30

The more layers we have, the higher the temperature goes - But each layer produces less warming than the last

Question 31

high clouds emit ___ and reflect ___

Answer 31

less, less ## Footnote warming effect, high and cold wispy clouds don't emit or reflect well

Question 32

low clouds emit ____ and reflect ____

Answer 32

more, more ## Footnote cooling effect, big warm fluffly clouds emit and reflect well