solar energy + energy budget

Question 1

what does the sun emit

Answer 1

Sun = 6000 degrees Celsius – emits high-energy shortwave radiation
- Solar radiation (shortwave) = 200-4000nm (0.2-0.4 um)

Question 2

what does earth emit

Answer 2

Earth = 15 degrees Celsius – emits low-energy longwave radiation
- Earth radiation (longwave) = 5000-25000nm (5.0-25.0 um)

Question 3

radiation inputs vs outputs?

Answer 3

input=shortwave
Output = longwave

Question 4

what are the major chemical components of the atmosphere

Answer 4

Nitrogen – 78.1 limiting
Oxygen – 20.9
Argon – 0.93
Carbon dioxide – 0.04

Question 5

what do gases in the air absorb?

Answer 5

Gases in the air absorb wavelengths:
CO2 – longwave lengths
H20 – shortwave lengths

Question 6

what are aerosols

Answer 6

small particles suspended in atmosphere

Question 7

describe aerosols

Answer 7

Natural (volcanic eruptions, dust, sea salt) or Anthropogenic
(pollution)
- Nuclei for water condensation
- High albedo (reflect incoming shortwave radiation – cooling effect)

Question 8

describe cloud impact on earth’s radiation budget

Answer 8

Clouds (H20) – complex effects on earths radiation budget
- High albedo (cooling)
- Absorb longwave radiation (warming, greenhouse gases)

Question 9

why is radiation balanced

Answer 9

Light energy (radiation from sun) overall balances the energy going out because of dynamic
balance in temperature

Question 10

how is incoming solar radiation budgeted?

Answer 10

Incoming solar radiation (shortwave)=100
- 30% reflected back in space (backscatter by air and clouds)
- 23% absorbed by atmosphere
- 50% reaches earth (less than 1% used by photosynthesis)

Question 11

why is earth radiatively balanced

Answer 11

As a global long-term average, Earth is close to a state of radiative balance that amount of
incoming (shortwave) = amount of outgoing (shortwave and longwave)

Question 12

atmosphere radiation budget?

Answer 12

Above atmosphere: 100=30+70 thus balanced b/c of thermodynamics
- Atmosphere: 156 input =156 output
- Surface: 145 input =116 output

Question 13

what is convection? divided into?

Answer 13

: Heat transfer by turbulent movement of air and water
sensible and latent heat flux

Question 14

define latent heat flux

Answer 14

Latent heat flux: energy transferred between a surface and the atmosphere by the
evaporation of water or the condensation of water vapor (phase change)

Question 15

define sensible heat flux

Answer 15

Sensible heat flux: energy conducted from a warm surface to the air immediately above it
and moved upward to the atmosphere (no phase change

Question 16

define natural greenhouse effect. what is its function?

Answer 16

Natural Greenhouse Effect: warming of atmosphere due to atmospheric absorption (by
radiatively active gases) of longwave radiation
-Maintains earth @ 15 degrees Celsius; without NGHE earth would be @33
degrees colder

Question 17

What are radiatively active gasses?

Answer 17

Radiatively Active Gases: absorb and re-radiate long wave radiation emitted by Earth (H20,
CO2, CH4, N2O, O3, CFCs)

Question 18

define mean residence times

Answer 18

Mean residence times (MRT): total mass divided by the flux into or out of the atmosphere over a
given time period

Question 19

MRT for N2, O2, CO2?

Answer 19

N2 MRT=13 million years
- O2 MRT=10,000 years
CO2 MRT=5 years

Question 20

what is spatial variation in climate due to

Answer 20

atmospheric structure

Question 21

describe troposphere?

Answer 21

Ends approximately 10-16km
- Temp declines with height
- Heated from below; absorbs LW radiation emitted from Earth
- WEATHER

Question 22

describe stratosphere

Answer 22

Above troposphere (to approximately 48km)
- Temp increased with height
- Heated from above (SW solar)
- UV protector, contains O3 which absorbs UV radiation

Question 23

describe stratopause

Answer 23

• Absorption of incoming radiation by the oxygen
• Filtering of UV radiation takes place

Question 24

describe thermosphere

Answer 24

Thermosphere:
- Increase in temp b/c of UV