Water Lesson 4: Water Budgets

Question 1

Define water budget

Answer 1

Shows the annual balance between inputs and outputs in the water cycle

Question 2

Positive water budget?

Answer 2

When precipitation exceeds evapotranspiration and there is a water surplus

Question 3

Negative water budget?

Answer 3

When evapotranspiration exceeds precipitation and there is water scarcity with an increased drought risk

Question 4

Water budget eqution?

Answer 4

Precipitation (P) = channel discharge (Q) + evapotranspiration (E) +/- change in storage (S)

Question 5

Define field capacity

Answer 5

When the soil store is at full capacity and cannot hold anymore

Question 6

Define soil moisture surplus

Answer 6

Precipitation greater than evapotranspiration. Run off recharges groundwater supply- the soil is at field capacity

Question 7

Define soil moisture deficiency

Answer 7

Soil water store has been used up. Plants will only survive if they have adaptations to survive periods of drought or they are irrigated

Question 8

Define maximum annual temperature

Answer 8

River levels will fall, crops will need irrigation

Question 9

Define soil moisture recharge

Answer 9

When evapotranspiration decreases so that it is lower than precipitation and the soil store will start to recharge

Question 10

Define soil moisture utilisation

Answer 10

Evapotranspiration exceeds precipitation. Water is being drawn up through the soil by capillary action- the water is being used up

Question 11

What is point A?

Answer 11

Soil moisture surplus

Question 12

What is point B?

Answer 12

Soil moisture utilisation

Question 13

What is point C?

Answer 13

Maximum annual temperature

Question 14

What is point D?

Answer 14

Soil moisture deficiency

Question 15

What is point E?

Answer 15

Soil moisture recharge

Question 16

What is point F?

Answer 16

Field capacity

Question 17

Why are soil moisture budgets useful?

Answer 17

-Show the impact on soil moisture availability in different climatic locations
-Useful for understanding the vulnerability of terrestrial ecosystems
-Identify challenges for agriculture, particularly with the presence of climate change

Question 18

Which two climates typically have a positive water balance?

Answer 18

Temperate and tropical

Question 19

What is the reason these climates have a positive water balance?

Answer 19

Low air pressure caused by the global air circulation

Question 20

In which month does Cairo have it’s highest average monthly precipitation? What is it?

Answer 20

December
8mm

Question 21

In which month does Barrow, Alaska have its highest average monthly precipitation? What is it?

Answer 21

July and August
24mm