5.7 physical and human causes of water insecurity

• define water stress


  When demand for water exceeds the supply, which can be caused by both climate and population
• define water security


  the ability of a population to access a sufficient supply of acceptable quality water
• what two things does water stress concern

  consumption and supply
• what two things can water stress be caused by

  climate and population
• explain how the climate can affect water stress


  -near the equator

  -lack of rainfall
• explain how the population can affect water stress

  a large population increases demand (eg) India has the largest population in the world
• define water scarcity


  where water availability is less than 1000m3 per person per year
• what two types of water scarcity are there

  physical scarcity and economic scarcity
• what is physical water scarcity


  where there uint enough water available, due to a lack of rainfall/ high evaporation etc
• what os economic water scarcity


  when there is enough water available, but a lack of money to exploit it
• by how much is demand for water increasing each year

  by 1%
• name 4 reasons why demand for water is increasing


  -population increase

  -middle class consumption

  -industrial growth

  -agricultural growth
• statistic to show population increase

  increased by 3.5 billion from 1992 - 2022
• what uses the most water

  agriculture
• what % of our water is used in agriculture

  70%
• what are two physical causes of water insecurity


  -climate variability

  -salt water encroachment
• explain how climate causes water insecurity

  -ENSO cycles affects precipitation and can cause droughts in South America

  -hot climates have increased evaporation

  -global warming
• what is salt water encroachment


  where groundwater stores near the coat of low lying countries become encroached with salt water as sea levels rise
• explain why salt water encroachment affects water security

  because freshwater stores become unusable as it is too expensive to desalinate water
• what are two human causes of water insecurity

  -over abstraction

  -contamination
• example of overabstraction from a river


  yellow river, china

  2x faster
• example of overabstraction from groundwater

  palestine

  pump out at 100,000 ft/year

  replenished at 73,000 ft/year
• explain how over abstraction creates winners and losers (so water security and insecurity). use an example

  Yellow River, china

  -being pumped to the capital Dakar for industry, so winners

  -riverside communities (eg) farmers who rely on irrigation from the river have a decreased supply = stress
• explain how even indirectly, over abstraction is a human cause


  -because fuelled by rising demand due to population growth, rising middle class, agriculture etc
• what 2 industries pollute water


  agriculture and industrial
• explain how farming is largely responsible for water pollution


  because farms are often located near rivers due to fertile soil and natural irrigation

  so fertilisers/ animal waste washed into rivers
• what is an example of agriculture polluting water

  river wye
• explain why industrial pollution/ agriculture is such a large issue (prioities)

  -water is used with economic priorities

  -70% of water used for agriculture
• explain why humans can mitigate water insecurity


  HICs can utilise globalisation to buy land in other countries with a good supply and extract water from there of lack a domestic supply
• by what % is increase in global agriculture expected to increase by 2050

  60%