Water

Question 1

How much of water supply is freshwater?

Answer 1

2.5%

Question 2

Where is the most freshwater found?

Answer 2

Lakes
Ice caps, glaciers, permafrost
Groundwater

Question 3

Why is demand for water increasing?

Answer 3

Population growth and economic development

Question 4

What is water security?

Answer 4

capacity of a population to safeguard sustainable access to adequate quantities of acceptable quality water for: sustaining livelihoods; human well-being and socio-economic development; ensuring protection against waterborne pollution or water-related disasters; preserving ecosystems in a climate of peace and political stability.

Question 5

What is an aquifer?

Answer 5

a layer of porous or permeable rock (such as chalk, limestone, sandstone or gravel) below the earth’s surface that is saturated with groundwater.

Question 6

Factors affecting water supply in rivers

Answer 6

Climatic factors (precipitation impacts on discharge)
Size of drainage basin

Question 7

Impacts of over-abstraction in rivers

Answer 7

Reduced flow downstream > sedimentation/less nutrients/impact on habitat change
Social (uneven distribution of resources

Question 8

Factors affecting water supply in reservoirs

Answer 8

Topography
Geology
Catchment area
Climate

Question 9

Impacts of over-abstraction in reservoirs

Answer 9

Flood control
Stored water supplies/miscellaneous benefits
Sedimentation reduces capacity
Microclimate
Alters river regime downstream: changes flow; habitat change; landform change

Question 10

Factors affecting water supply in aquifers

Answer 10

Abstraction vs recharge rates

Question 11

Impacts of over-abstraction

Answer 11

Subsidence
Sinking of water table: loss of wetlands; increasing unreliability of rivers
Saltwater intrusion
Drying of soils
Human: impacts on agriculture, pumping costs etc.

Question 12

Describe global patterns of water demand

Answer 12

High demand: larger population; high domestic industrial/agricultural use/wealth
Low demand: poor water infrastructure; limited industrial development

Question 13

What is water stress?

Answer 13

Annual supply of water per person is less than 1,700m3. Demand for water has exceeded the amount of water available or poor quality water has restricted the amount available.

Question 14

What is water scarcity?

Answer 14

below 1,000m3/per person/year

Question 15

What is physical scarcity?

Answer 15

more than 75% of river flows being used/natures provision of water is insufficient to meet populations need. Less than 500 mm of rainfall annually

Question 16

What is economic scarcity?

Answer 16

human and financial factors limit water use to less than 25% of river flows

Question 17

What are the physical factors that affect water supply?

Answer 17

Climatic:
Precipitation levels (latitude; wind direction; proximity to coasts)
Evaporation rates (latitude; proximity to coasts)

Geological:
Permeability of rock

Drainage:
Capacity and size of drainage basin systems

Question 18

What are three main components of water demand?

Answer 18

Agricultural use (70%)
Industrial and commercial use (22%)
Domestic/household use (8%)