Key Definitions

Question 1

Anticyclone

Answer 1

A system of high pressure, causing high temperatures and unseasonably high evaporation rates

Question 2

Aquifer

Answer 2

A permeable or porous rock that stores water

Question 3

Channel flow

Answer 3

Water flowing in a stream or river

Question 4

Conventional precipitation

Answer 4

Solar radiation heat the air above the ground, causing it to rise, cool and condense forming precipitation

Question 5

Cryosphere

Answer 5

The global water volume locked up within a frozen state

Question 6

Depression

Answer 6

A system of low pressure, with fronts of precipitation where low and high pressure air masses meet

Question 7

Desalination plant

Answer 7

The conversion of seawater to freshwater, suitable for human consumption

Question 8

Desublimation

Answer 8

The change of state of water from gas to solid without being a liquid

Question 9

Drainage basin

Answer 9

The area of land drained by a river and its tributaries

Question 10

Drainage density

Answer 10

The total length of all rivers and streams divided by the area of the drainage basin

Question 11

Drought

Answer 11

An extended period of deficient rainfall relative to the statistical average for the region

Question 12

Economic water scarcity

Answer 12

When water resources are available but insufficient economic wealth limits access to it

Question 13

ENSO cycles

Answer 13

El Niño Southern Oscillations - naturally occurring phenomena that involves the movement of warm water in the Equatorial Pacific

Question 14

Evapotranspiration

Answer 14

The combined total moisture transferred from the Earth to the atmosphere through evaporation and transpiration

Question 15

Frontal precipitation

Answer 15

Where air masses of different temperatures meet at a front, one mass will be forced over another, causing precipitation beneath the front

Question 16

Global hydrological cycle

Answer 16

The continuous transfer of water between land, atmosphere and oceans. The Earth is a closed system

Question 17

Groundwater flow

Answer 17

Water moving horizontally through permeable or porous rock due to gravity

Question 18

Hydrological drought

Answer 18

Insufficient soil moisture to meet the needs of vegetation at a particular time

Question 19

Infiltration

Answer 19

The movement of water vertically through the pores in the soil

Question 20

Interception

Answer 20

Raindrops are prevented from falling directly onto the ground, instead hitting the leaves of a tree

Question 21

Meteorological drought

Answer 21

When long term precipitation trends are below average

Question 22

Monsoon

Answer 22

The drastic variation between wet and dry seasons for subtropical areas, caused by a changed prevailing wind. Can lead to annual flooding

Question 23

Open system

Answer 23

A system affected by external flows and inputs e.g. drainage basin

Question 24

Percolation

Answer 24

Water moving vertically from soil into permeable rock

Question 25

Physical water scarcity

Answer 25

A physical lack of available freshwater which cannot meet demand

Question 26

Relief precipitation

Answer 26

Precipitation caused when air masses are forced to rise over high land, determined by the morphology of the land

Question 27

River regime

Answer 27

The pattern of river discharge over a year

Question 28

Runoff

Answer 28

Water flowing over the surface of the ground e.g. after precipitation or snowmelt

Question 29

Salinisation

Answer 29

Where salt water contaminates freshwater stores or soils, creating saline conditions and reducing human consumption

Question 30

Saltwater encroachment

Answer 30

The movement of saltwater into freshwater aquifers or soils. This may be caused by sea level rise, storm surges or over extraction

Question 31

Smart irrigation

Answer 31

Providing crops with a water shortage supply less than optimal, to make crops resistant to water shortages

Question 32

Storm hydrographs

Answer 32

Variation of river discharge over a short period of time (days)

Question 33

Sublimation

Answer 33

The change of state of water from a solid to a gas, without being a liquid

Question 34

Thermohaline circulation

Answer 34

The movement of volumes of seawater from cold deep water to warm water surface water

Question 35

Throughflow

Answer 35

Water moving horizontally through the soil, due to gravity

Question 36

Transpiration

Answer 36

The process through which water evaporates through the stomata in a leaf

Question 37

Water budget

Answer 37

The annual balance between inputs and outputs in a system

Question 38

Water conservation

Answer 38

Strategies to reduce water usage and demand

Question 39

Water recycling

Answer 39

The treatment and purification of waste water, to increase supply

Question 40

Water scarcity

Answer 40

There are limited renewable water sources

Question 41

Water security

Answer 41

The ability to protect and access a sustainable source to adequately meet demand

Question 42

Water sharing treaty

Answer 42

International agreements for trans boundary sources

Question 43

Water transfer

Answer 43

Hard engineering projects, such as pipelines or aqueducts that divert water between basins to meet demand

Question 44

Watershed

Answer 44

The boundary between neighbouring drainage basins