Hydroclimatology

Question 1

what’s the difference between climate and weather?

Answer 1

Climate- 30 year average of atmospheric information such as rainfall, temperature and pressure
Weather - shorter term variability about these average conditions

Question 2

How is incoming radiation filtered by the atmosphere and earth surfaces? (3)

Answer 2

• reflected or absorbed by the atmosphere or earth surfaces
• reflected not involved in earths climate system (back to space)
• absorbed radiation allows conversion between energy types, heat production and exchange which drives the global climate system

Question 3

Name the 2 components that reflection of incoming radiation is made up of?

Answer 3

Clouds

Molecules and dust/aerosols

Question 4

What is the largest agent of reflection and radiation filtering in the earth system?

Answer 4

Clouds

+ reflecting 20% of incoming solar radiation

Question 5

What is Rayleigh scattering?

Answer 5

When incoming radiation is reflected by water vapour, dust and air molecules

Question 6

Difference between direct and diffuse radiation?

Answer 6

Direct - travelling in the same beam direction

Diffuse - travelling in all directions so produced less shadow

Question 7

What is the difference between the wavelengths it ozone/ aerosols and water vapour?

Answer 7

Ozone/ aerosols - short wavelengths

Water vapour - longer wavelengths

Question 8

What is ‘global’ radiation?

Answer 8

The sum of diffuse and direct radiation

Question 9

How to calculate net shortwave radiation

Answer 9

Total absorbed - total reflected = net shortwave radiation

Question 10

What is the ratio of radiation absorbed and reflected at the earth surface?

Answer 10

Absorbed 70%

Reflected 30%

Question 11

Explain how the balance of outgoing longwave radiation prevents overheating?

Answer 11

• trapping LW radiation gives earth a warmer temperature

- loss to space prevents overheating

Question 12

What is global warming?

Answer 12

Addition of greenhouse gases to the atmosphere, more molecules to trap outgoing long wave radiation

Question 13

Difference in shortwave radiation between the tropics and the poles?

Answer 13

Tropics recieve more shortwave radiation than they emit

Poles emit more than received

Question 14

What happens to the shortwave radiation absorbed at earths surface?

Answer 14

• > 50% re emitted as long wave radiation

- the rest is used to drive the surface energy balance providing linked to the hydrological cycle

Question 15

What is latent heat?

Answer 15

Where heat is transferred to drive a phase change with no change in temperature

Question 16

What is sensible heat?

Answer 16

Where heat transfer ones increase the temperature

Question 17

Difference in the energy used from latent and sensible heat on land and water?

Answer 17

• latent: used to change state of water

- sensible: used to change temperature of atmosphere

Question 18

What is ground heat flux energy used for on land and water?

Answer 18

To change the temperature of ground surface

Question 19

What is net radiation used for?

Answer 19

Direct heat transfers e.g latent heat flux and sensible heat

Question 20

How does latent heat flux link energy and water balances?

Answer 20

• evaporation from the ocean

- soil evaporation and transpiration from plants

Question 21

Where is most of the earths heat stored?

Answer 21

In the oceans

Question 22

How does the atmosphere remain saturated?

Answer 22

• evaporation increases water vapour conc in atmos
• condensation reduces it
  When these two values are equal

Question 23

Name 3 main types of humidity?

Answer 23

• absolute humidity
• relative humidity
• specific humidity

Question 24

Define absolute humidity

Answer 24

Total amount of water vapour in the atmosphere (doesn’t take temperature into account)

Question 25

Define relative humidity

Answer 25

The ratio of measured humidity to saturated humidity at that temperature

Question 26

What is a cold front?

Answer 26

Cold air moving to replace warm air

Question 27

Explain convection

Answer 27

Vertical transport of less dense noisy air higher in the atmosphere where it can cool

Question 28

Describe a monsoon

Answer 28

Where warm moist air from the ocean meets a very warm land surface to drive very deep convection high into the atmosphere

Question 29

What is the main mechanisms to make rain?

Answer 29

Cooling the air by forcing it higher into the atmosphere

Question 30

What is precipitation recycling?

Answer 30

When vegetation pumps a lot of water back into atmosphere and this is reused as rainfall

Question 31

Define an aerosol in climate context

Answer 31

suspension of fine solid particles in the air

Question 32

What is the role of reflected radiation in the earth’s climate?

Answer 32

None, it goes back to space

Question 33

Describe the albedo of water surfaces?

Answer 33

very low

Question 34

What is specific humidity?

Answer 34

The mass of water vapour in a parcel of air compared to the total mass of the air parcel

Question 35

The atmosphere is mostly ___ to shortwave radiation

Answer 35

transparent

Question 36

How much of total incoming energy is reflected by the earth itself?

Answer 36

A small fraction

Question 37

Which landscape has a higher albedo?
- bare soil and deserts
OR
- vegetation or agriculture

Answer 37

bare soil and deserts

Question 38

What makes a good absorber?

Answer 38

Poor reflector

Question 39

What is outgoing radiation?

Answer 39

the re emission of radiation if heating of a substance occurs

Question 40

Why is the earths average temperature higher than what it should be?

Answer 40

because the atmosphere is delaying and storing the transfer of heat away from the earth