1.6. Factors Driving Change in Magnitude of Water Stores

Question 1

What is evaporation?

Answer 1

Occurs when liquid water changes state into a gas, becoming water vapour

Question 2

What does evaporation do?

Answer 2

Increases amount of water stored in atmosphere

Question 3

How do rates of evaporation change?

Answer 3

By location and season

Question 4

What will a large supply of warm dry air cause?

Answer 4

High rates of evaporation

Question 5

What is accumulation?

Answer 5

freezing

Question 6

What is ablation?

Answer 6

melting

Question 7

What do accumulation and ablation do?

Answer 7

Change the amount of water stored in the cryosphere

Balance changes with temps

Question 8

What happens during cold periods?

Answer 8

Inputs > outputs
(water transferred as snow and less through melting)

Question 9

What does the earth go through?

Answer 9

Natural warming and cooling by changes in the earth’s orbit every 100,000 years

Changes can occur in shorter timescales e.g. seasonal and industrial revolution

Question 10

What is happening to most glaciers?

Answer 10

They’re shrinking

Question 11

How may years ago was the peak of the last ice age and how much of the earth’s surface was covered in ice sheets?

Answer 11

• 21,000 years ago
• 1/3 of the earth’s surface

Question 12

How much lower were sea levels at the peak of the last ice age

Answer 12

100m lower

Question 13

What could melting of Antarctica and Greenland ice sheets cause sea levels to do?

Answer 13

rise by 60m

Question 14

+ve feedback of climate change

Answer 14

Rising sea levels will make ice sheets break which will cause further melting

Question 15

What happened 3 million years ago?

Answer 15

Sea levels were 50m higher than today (warmer period)

Question 16

When does condensation occur?

Answer 16

• When water vapour becomes a liquid and loses energy to its surroundings.
• When water condenses, it releases latent heat.
• Happens when air containing water vapour cools to its dew point e.g. when temps fall at night as heat is lost to space.
• Water droplets can stay in the atmosphere or move to other subsystems.

Question 17

What has the greatest control on condensation?

Answer 17

Temperature -> lots of water vapour and decreased temps = high condensation

Question 18

What is frontal rain?

Answer 18

Where less dense warm air meets denser cool air, the warm air rises and cools -> vapour condenses to form frontal rain

Question 19

What is relief rain?

Answer 19

Where warm air meets mountains, it’s forced to rise and cool -> vapour condenses to form relief rain

Question 20

What is convectional rain?

Answer 20

When the sun heats up the ground, moisture rises as a column of warm air. This then cools and vapour condenses to make convectional rain (global atmospheric rain).