Water EQ3 Flashcards
Explain the UN findings on water scarcity?
- effects ever continent - around 1.2 billion people live in areas of physical scarcity, while 1.6 billion face economic water shortage
- both a natural and a human-made phenomenon - enough freshwater however it is evenly distributed and too much is wasted and polluted
Define water scarcity?
An imbalance between demand and supply, classified as physical scarcity (insufficient water to meet demand) or economic scarcity (people can’t afford water though its available)
Define water stress, what may cause water stress?
If a country’s water consumption exceeds 10% of its renewable freshwater supply, including difficulties in obtaining new quantities of water, as well as poor water quality restricting usage
- together these terms add up to water insecurity - leading to a need for physical, political or economic solutions
Explain why there may be an increase in water pollution?
- Warmer waters (from climate change) encourage the growth of bacteria and other organisms that are harmful to human health
- The quality of water may be affected by sedimentation, nutrient enrichment, dissolved organic carbon, pathogens, pesticides and salt, with possible negative impacts on ecosystems and human health
Explain the effect of sea levels rising on freshwater supplies, why is this happening?
Sea level rise and localised abstraction of groundwater are increasing the risks of saltwater intrusion into coastal areas - extensive groundwater pumping from fresh water wells lowers the water table and allows saltwater to move into soils and aquifers
- thermal expansion of sea + melting ice sheets and glaciers allows saltwater to intrude further inland
Explain the reason behind increasing demand for freshwater resources?
Population growth, urbanisation and industrialisation along with increases in production and consumption have increased demands for freshwater resources (agriculture uses 70% globally)
- strong income growth and a growing middle class has led to sharp and unstable increases in water use, especially in regions where supplies are already vulnerable and where there is a lack of management / regulation
Explain the significance of water regarding agriculture, human factor?
Agriculture is the human activity with the largest water use (70% globally and 90% in developing countries)
- millions of farmers rely on groundwater to sustain their livelihoods and ensure food security - however levels are declining in some of the worlds most intensive farming areas (eg Beijing)
Explain 2 factors affecting water availability?
- Pollution and contamination - due to intensive agriculture (use of chemical fertilisers and pesticides), industrial production (waste and chemicals) or untreated sewage (contains harmful bacteria)
- many cities in developing countries do not have the sufficient infrastructure in place to collect and treat sewage - estimated that in developing counties 90% of all waste water is discharged directly into rivers, lakes and oceans
Explain how expansion of commercial agricultural has affected water?
Has led to increases in nitrate and phosphate fertiliser applications, causing eutrophication of freshwater ecosystems and significant environment and health risk
Explain the physical factor topography and distance and how it affects water insecurity?
High relief promotes increased precipitation and rapid run-off, but may also provides greater opportunities for surface water storage in natural lakes and artificial reservoirs, especially where it is combined with impermeable geology
Explain the physical factor determining water insecurity refer to climate?
Climate determines the global distribution of water supply - precipitation varies globally as a result of atmospheric pressure systems with low-pressure zone of mid-latitudes and equatorial regions having the highest totals and therefore being water secure
- short term climate change (ENSO) are exacerbating the water security situation
Explain how the physical factor geology controls the distribution of aquifers?
Permeable chalk and porous sandstones can store vast quantities of water underground, which is valuable as it is not susceptible to evaporation loss
- water supply can be access by wells or springs - giving an even supply throughout the year
Explain how steep relief affects water security - physical factors?
- Steep relief locations have more relief rain and also more run-off and surface storage in lakes/reservoirs, especially in mountainous impermeable geology - may reduce insecurity
Explain how physical factors like rivers affect water insecurity?
Worlds major rivers systems store large quantities of water and transfer it across continents, disruptions to these can cause droughts eg those in Brazil 2005 and 10 which covered and area twice the size of California, resulted in flows in the river at an all time low
- eg the Amazon has an annual discharge of 175,000 cubic m/s - transports a huge amount of water
Explain how saltwater encroachment can occur?
Sea level rise (from thermal expansion a result of warming temperatures) and increased severe weather systems can result in saltwater intrusion into many coastal regions - this paired with extensive groundwater abstraction and a lower water tables can result in saltwater penetrating soils and aquifers
- storm surges can lead to flooding of low-lying land and erosion
Explain the affect of industrialisation on water security?
OECD predicted global water demand from manufacturing would increase by 400% from 2000 to 2050 (greatest in any sector) - most of this increase will be in emerging economies and developing countries
- in these regions where water use is not well regulated, pollution could increase dramatically leading to contamination of ground water and rivers
Explain 4 factors the inefficient use of water for crop production is causing?
- depleting aquifers and reducing river flow
- degrading wildlife habitats
- increasing pesticide and fertiliser pollution (seeping into groundwater)
- causing increased salinity (20% of worlds irrigated land suffers from salinity)
Explain how the human factor over abstraction is causing water insecurity?
When too much water is removed ground groundwater the supplies diminish - estimated 20% of of the worlds aquifers are over-exploited
Explain two types of common pollution affecting water security?
- untreated sewage disposal (especially in developing counties) causes water-borne diseases such as typhoid and cholera - in India only 20% of sewage is treated before entering rivers - by 2020 WHO estimate 135 million people could die unnecessarily from these water-born diseases
- chemical fertilisers uses increasingly by farmers contaminate groundwater and rivers - causing eutrophication in lakes and rivers, leading to the formation of dead zones in coastal water
Explain how the increases in the energy industry is a threat for water security?
Energy industry requires increasing amounts of water for new energy developments such as biofuels and fracking
- power plants use lots of water to generate steam to turn turbines
Explain the reason for rising demand for water, give figures/evidence?
United Nations world water development projected an increase in global water demand of 55% by 2050 - mainly due to a growing demand from secondary industries ,thermal electricity generation and domestic use, all of which are linked to increasing urbanisation in developing countries
- UN projects a 40% global water deficit by 2030 if nothing is done
Explain what physical scarcity is?
occurs not enough water to meet all demands, including environmental flows. Arid regions are most often associated with physical water scarcity, but water scarcity also appears where water is apparently abundant, when water resources are overcommitted to various users owing to overdevelopment of hydraulic infrastructure, most commonly for irrigation purposes
Explain what economic scarcity is?
Shortfall in available water is related to shortfalls in Human Resources such as capital, technology and sound governance - assumption is that the water potential is there, but it waits to be exploited
Explain why there is increasing global demand for water?
World population is growing by 80 mil a year, and is expected to be 9.1 bn by 2050 - the demand for water is rising twice as fast as population growth and the increasing population living in urban areas (6.3bn by 2050) means there will be extreme stress in these high density areas for water, developing regions will not be able to cope due to insufficient infrastructure or water available
Explain how transport can affect water price?
Transporting water from source to consumption - in California expensive pipes transport from mountain reservoirs to coastal cities
- may not have infrastructure in place in slum regions
Explain how significant urban growth is increasing the price of water?
Colonial governments installed limited infrastructure for water supplies - massive urban growth has now outgrown this limited infrastructure
Explain how privatisation has affected water prices?
In many countries the water supply has been passed onto private sector companies Profits have risen for companies and in many cases supply has fallen and costs for consumers risen
- water is more expensive
Explain how poverty affects water prices?
Poverty and insufficient water infrastructure
in squatter settlements e.g. Accra in Ghana.
Poor residents must rely on water tankers
and bottled water
- In Manilla these are 4x
more expensive than piped water
