Water Scarcity Flashcards
What is an arid region
Receive less than 250mm of rain per year
High rainfall variability
Healthcare said
1983
0.17% out of 0.54 fresh water resources are found in arid region
Unevenly distributed and most not immediately accessible
UNESCO
2003
Ground water is the worlds most extracted resource
Why does the replenishment rate of GW vary
1- land use change
2- changes in surface water
3- lowering of water table
4- LT climate cycles
Why does quality of GW vary
Salinisation
Contamination from inadequate sewage infrastructure
Natural contamination
What are the main problems in arid regions
Access
Poor quality
Competition
Limited potential for improving quality and quantity
BUT addressing anyone of these issues could ruin another
Quinn Said
2009
Groundwater depletion India
India abstracts more groundwater than the 2nd and 3rd highest consumers combined
In NW India depletion of aquifers with western farming techniques largely to blame
Abstraction rate higher then the replenishment rate
Decline in water table
Micklin
2007
Aral Sea water was diverted from Amu-darya and Sry-Darya for irrigation
Over 60% of water was lost over a period of 30 years creating poisonous levels of salinity
Over 60 million rely on this basin
Drought
Natural and temporary phenomenon and is characterised as a deviation from normal conditions
NO universal definition of drought
American Meteorological Society
1997 4 different types of drought -meteorological precipitation deficit -hydrological sub surface supple deficit -agricultural lack of soil moisture -socio economic supply but can’t access
What’re scarcity
A natural and human made phenomena when demand exceeds supply
UN 2014
Enough water for 7 billion ppl but it’s distributed unevenly and mischief is polluted and wasted
- 2 billion live in areas of physical water scarcity
- 6 billion live in areas of economic water scarcity
Water stress
The ability or lack of to meet human and ecological demands
How many effected by water stress
30 countries under water stress- 20 under absolute water scarcity
Allom
2001
Water stress can be alleviated in areas such as Syria and Jordan where water intensive communities can be imported
Environmental agency 2007
Pets if SE England have less water per person than Sudan or Syria
Example of water stress management in EU
Policy based on principle of water hierarchy
Additional water supply infrastructure should only be considered when all demand measures have been exhausted
Member status are encouraged to focus on prevention methods
What is desertification
Degradation of land and vegetation
Soil erosion
Infertile lands in arid area
Causation- Human activities and climate variation
Van Loon
2016
Hydrological cycle is intertwined with human influence cannot spears the 2
Drought can be caused by human or physical influences
Human impacts on earth are increasing- new epoch
Human activities shape water availability no longer view drought at an external hazard
Houses of Parliament said
2012
Responses mainly in hands of private water companies and users
The choose to increase demand is having a negative effect on ecosystem in freshwater bodies
Drought in UK occur approx every 7 years
Areas with highest pop receive lowest rainfall
Sheffield et al
2012
Drought expected to increase frequency and severity due to climate change
Calculations using Palmer drought severity index suggest global moisture levels are decreasing since 1970
Critiques this method arguing little changes in drought for 60 years
Marris
2016
Klamath river USA
Travels from south Oregon to CAlifornia
Multiple management
Farmers use water for irrigation will indigenous and environmentalists want to stop this
Tension heightens every summer when water drys for 3 months
Management done every month
Rodell et al
2009
GW is a primary source of freshwater in many parts of the world
But some regions are overly reliant upon it
NW India
114,000,000 rely on water basins however, excess irrigation is creating unsustainable depletion of basin
