The water cycle and water insecurity

Question 1

Water stress

Answer 1

the demand for water exceeds the available amount during a certain period. If renewable water resources are between 1,000-1,700 m3 per capita per year. Restrictions for usage as well as conflict for water supplies

Question 2

Water scarcity

Answer 2

between 500-1,000m3 (renewable) per capita per year, usually open tension, and conflict

Question 3

Absolute water scarcity

Answer 3

renewable water sources are very low (less than 500m3 per capita), resulting in widespread restriction on use

Question 4

Economic water scarcity

Answer 4

when access to water is limited by capital, technology, and governance

Question 5

Physical water scarcity

Answer 5

more than 75% of a countries or regions population water is being used

Question 6

Saltwater encroachment

Answer 6

when salt water contaminates freshwater

Question 7

Transboundary

Answer 7

water crossing political borders

Question 8

Stores

Answer 8

these are the stores of water, places where the water is held. For example, the oceans

Question 9

Fluxes

Answer 9

this is the flow of water between the stores (and the rate/speed of flow)

Question 10

Processes

Answer 10

the physical factors which drive the fluxes of water between the stores

Question 11

The Hydrological Cycle

Answer 11

• Example of a closed system. No water is added to the global water budget, and none is removed
• The system is driver by solar energy and gravitational potential energy
• The water is held in different states (solid, liquid, gas) and stores which vary for both human and physical factors

Question 12

Residence times

Answer 12

these are the average times a water molecule will spend in a reservoir or store

Question 13

Fossil water

Answer 13

nonrenewable and reachable water for human use (e.g., deep groundwater found in the Sahara Desert

Question 14

Drainage basin cycle

Answer 14

• subsystem within the global hydrological cycle
• It is an open system with eternal inputs and outputs that cause the amount of water in the basin to vary over time

Question 15

Antecedent

Answer 15

a thing or event that existed before or logically proceeds another

Question 16

Water budgets

Answer 16

• annul balance between inputs (precipitation) and outputs (the channel flow and evaporation)
• More outputs than inputs = deficit (then causes droughts)
• More inputs than outputs = surplus (causing flooding)
• more than enough water (this is called a positive water balance)
• not enough water (this is called negative water balance)

Question 17

River Regimes

Answer 17

average annual pattern of discharge of a river, measured at a particular point

Question 18

Storm Hydrograph

Answer 18

a graph that shows how a river changes as a result of rainfall, it shows rainfall and discharge

Question 19

Discharge

Answer 19

the amount of water in a river at particular point

Question 20

Meteorological drought

Answer 20

This happens when long-term precipitation is lower than. It changes for different regions as it is affected by the atmospheric (Brazil)

Question 21

Agricultural drought

Answer 21

a situation where lack of rainfall or dry soil significantly impacts farming and crop growth (Brazil)

Question 22

Hydrological drought

Answer 22

situation where there’s a reduction in the water supply, specifically impacting water levels in rivers, lakes, reservoirs, and groundwater sources (Egypt)

Question 23

Socio-economic drought

Answer 23

the impact of water scarcity on human activities and livelihoods (London, California)

Question 24

Ecosystem functioning

Answer 24

the biological, chemical, and physical processes that take place within an ecosystem

Question 25

Ecosystem resilience

Answer 25

refers to the capacity of an ecosystem to recover from disturbance or withstand ongoing pressures. Levels vary, however desert and semi-arid ecosystems tend to be the most resilient

Question 26

Flash floods

Answer 26

- Occurs quickly and unexpectedly after heavy rainfall, often with little infiltration and rapid runoff. - Very dangerous due to their sudden onset and potential for significant damage. - Example: 2013 Sardinia floods caused by thunderstorms resulted in 18 deaths and $1.14 billion in damage.

Question 27

Monsoons

Answer 27

- Cause: Seasonal change in wind direction. - Impact: Heavy rainfall in India and Southeast Asia between April and September. - Rainfall Distribution: 70% of average rainfall occurs in 100 days.

Question 28

Snowmelt

Answer 28

* Impact: Snowmelt in high latitudes and mountain areas can increase river capacity. * Melting Pattern: Melting snow in late spring primarily affects Asia and America. * Glacial Outbursts: Glacial outbursts, known as jokulhlaups, can occur in regions like the Himalayas and Iceland, releasing large volumes of meltwater.