5.3 - water security Flashcards
What are players?
Individuals, groups or organisations with an involvement or interest in a particular issue
What percentage of water is usable/accessible by humans?
2.5% is freshwater, 1% of this available as easily accessible surface water
What is ‘peak water’?
The state of growing constraints on quantity and quality of accessible water
What are the issues with physical distribution of water?
There is a mismatch between where water supplies are and where demand is. 60% of supplies are contained in just 10 countries and 66% of population live in areas receiving only 25% of annual rainfall
What factors are driving rising demand for water?
population growth
rising standards of living (higher consumption of water from meat rich diets etc)
economic growth increasing demand in all economic sectors
irrigated farming
What is fracking?
A technique to harness gas and oil in which rock is fractured by a pressurised liquid
Why are water supplies dwindling?
diminishing supplies available from groundwater aquifers (main cause of over abstraction = irrigation)
drought etc putting pressure on supplies and leading to a falling water table
groundwater supplies are being extracted faster than they are replenished
What are the reasons for pressure points (water supplies under threat)?
diminishing supply
rising demands
competing demands from users
What is the water availability gap?
Imbalance between supply and demand due to variations in usage (distribution and demand tend not to coincide)
How much of the world’s population are predicted to be water vulnerable by 2050?
Around half
What is virtual water?
The hidden flow of water when food or other commodities are traded
What is physical scarcity?
When more than 75% of a country or region’s blue water flows are being used
What is economic scarcity?
When the development of blue water sources is limited by lack of capital, technology and good governance
What are physical factors determining the supply of water?
Macro scale - climate determines the global distribution of water supply via distribution of precipitation.
Other factors:
- atmospheric pressure systems
- ENSO
- topography, distance from sea
- geology
What are human factors influencing the quality of water supplies?
Human actions can pollute both surface and groundwater supplies.
- contaminated water e.g. China due to industry
- untreated sewage disposal
- chemical fertilisers causing eutrophication
- dams affect sediment movement
What are the human factors affecting the quantity of water supplies?
Over abstraction for domestic, agriculture and industrial usage.
Other drivers = urbanisation, population growth, rising living standards, industrialisation, economic development
- salt water incursion
What is the water poverty index, what indicators does it use
An assessment of the degree of water shortage and subsequent water insecurity problems.
Uses five parameters:
- resources
- access
- capacity
- use
- environment
What is water insecurity?
The lack of adequate and safe water for a healthy and productive life.
What is the problem of water insecurity related to?
availability (supply AND distribution network)
access
usage
What is physical scarcity determined by?
Climate (balance between precip inputs and EVT outputs).
At a local scale, geology and topography may be more significant
What is economic scarcity determined by?
Often associated with developing countries that lack capital and technology and good governance to fully exploit often adequate blue water sources
What factors determine the price of water?
physical costs of obtaining supply
degree of demand for water
whether or not there is sufficient infrastructure
who supplies the water