Water Resources

Question 1

True/False
Water Resources Management includes calculating both hydropower and irrigation water demand.

Answer 1

True

Question 2

Agriculture consumes about ___% of global blue water withdrawals.

Answer 2

70%

Question 3

What proportion of global food is produced in artificially irrigated areas?

Answer 3

40 %

Question 4

Water stress → __
Water scarcity → __

Answer 4

• Demand exceeds supply or poor quality limits use
• Annual supply < 1000 m³ per person

Question 5

An annual supply < ___ m³/person is water stress
< ___ m³/person is water scarcity.

Answer 5

1700
1000

Question 6

What is virtual water?

Answer 6

The water used in the production of goods or services

Question 7

Green water → __
Blue water → __
Grey water → __

Answer 7

Rainwater evaporated
Surface/groundwater evaporated
Polluted water volume

Question 8

List three major uses of water in human activities.

Answer 8

Domestic, Irrigation, Industrial (plus Commercial, Mining, Thermoelectric, etc.)

Question 9

Formula
Irrigation requirement:

Answer 9

I = Ep − P + R

Question 10

Irrigation Water Demand
Ks = 1 →
Et = Ep →

Answer 10

• Optimal growing conditions
• No water stress

Question 11

Kc depends on:

Crop type → __
Climate → __
Soil → __

Answer 11

• Albedo, height, stomata
• Wind, humidity
• Planting density

Question 12

Kc values vary by growth stage: Initial, Development, ____, ____

Answer 12

Mid-season, Late-season

Question 13

True/False
Kc values are fixed across crop life cycle.

Answer 13

False (they vary by stage)

Question 14

Formla
Total Available Water (TAW):

Answer 14

TAW = (θFC − θWP) × Zr
θₓfc = Volumetric water content at field capacity
θₓwp = Volumetric water content at wilting point
Zᵣ = Root depth

Question 15

Field Capacity (FC) = suction of __
Wilting Point (WP) = suction of __

Answer 15

• −0.33 bar
• 15 bar

Question 16

Formula
RAW =

Answer 16

p × TAW
RAW = Readily Available Water (mm or m³/m²)
p = Depletion factor (dimensionless, crop-specific; e.g. 0.3–0.7)
TAW = Total Available Water (mm or m³/m²)

Question 17

True/False
Applying water above RAW reduces stress without losses

Answer 17

False (can cause seepage losses)

Question 18

List two surface irrigation types.

Answer 18

Basin, furrow (others: flood, border-strip, etc.)

Question 19

Sprinkler irrigation → __
Micro-irrigation → __

Answer 19

• Simulates rainfall
• Drip/trickle systems

Question 20

True/False
Drip irrigation reduces salinisation risk.

Answer 20

False (it increases salinisation due to evaporation)

Question 21

Key human drivers of hydrological change include: urbanisation, agriculture, forestry, and ______.

Answer 21

climate change

Question 22

True/False
Forests reduce water runoff and stabilise catchment hydrology.

Answer 22

True

Question 23

What is the principle of natural flood management?

Answer 23

Using natural processes to reduce flood risk, such as restoring wetlands or reforesting catchments.

Question 24

What is “water sowing and harvesting”?

Answer 24

Traditional methods to store water in landscapes, especially in high-altitude Andean regions.

Question 25

What are greenhouse gases?

Answer 25

Gases that absorb and re-emit longwave radiation, warming the atmosphere.

Question 26

True/False Greenhouse gases block both longwave and shortwave radiation

Answer 26

False (transparent to shortwave, absorb longwave)

Question 27

Formula Boltzmann Law:

Answer 27

F = εσT⁴ Where F = radiated energy, T = temperature, ε = emissivity, σ = Boltzmann constant

Question 28

Formula Wien’s Law:

Answer 28

λmax = 2897 × 10⁻⁶ / T

Question 29

Sun temperature → Earth temperature →

Answer 29

- shortwave radiation - longwave radiation

Question 30

What do GCMs simulate?

Answer 30

The global climate system and hydrological exchanges of energy and water.

Question 31

True/False GCMs only simulate atmospheric processes

Answer 31

False (they include ocean, land, hydrology, etc.)

Question 32

Projecting climate change requires assumptions about ______ scenarios.

Answer 32

socio-economic

Question 33

True/False Climate models can reproduce current temperature trends using only natural forcings.

Answer 33

False

Question 34

Hydrological Processes in GCMs Evapotranspiration modelled with → __ UK Met Office model → __

Answer 34

- Penman-Monteith - MOSES land surface model in HadCM3

Question 35

What is the spatial resolution of the HadCM3 atmospheric model?

Answer 35

~417 km × 278 km (too coarse for most catchments)

Question 36

To use GCMs locally, projections must be _______.

Answer 36

downscaled

Question 37

True/False Downscaling adds certainty to model outputs.

Answer 37

False (it introduces new uncertainties)

Question 38

Why is there often a mismatch between GCMs and hydrological needs?

Answer 38

Because GCM resolution is too large to capture local hydrological processes.

Question 39

Name two local hydrological impacts of climate change.

Answer 39

Changes in river flow, shifts in seasonal runoff patterns

Question 40

True/False GCMs are accurate enough to directly assess water risks in small catchments

Answer 40

False