Miss McDonald EQ3 Flashcards
Water scarcity
Imbalance demand+supply:physical scarcity not enough water meet demand, econ scarcity ppl can’t afford it (below 1000m^3per person)
Water stress
If a country’s water consumption exceeds 10% renewable freshwater supply (difficulties obtaining new quantities, poor water quality usage) (below 1,700m^3per person)
Water insecurity
Where present and future supplies can’t be guaranteed-need physical/pol+econ solution
Water stress facts
- by 2050 2/3rds approx 5.5bn living water stress
- atm SA, India, E Africa main areas+ high density EU countries e.g. SE UK
Water scarcity facts
- 1.2bn 1/5pop physical scarcity, 500m approaching
- 1.6bn almost 1/4 econ water shortage as water demand growing 2x rate pop increase last century
- N Africa, Middle East, Asia e.g. Saudi Arabia, Oman, Yemen etc spreading much more 2025 include India, China+Central Asia
Global mismatch supply and demand
- Est 60% accessible freshwater used in theory plenty future use but…
- 66% pop live areas receiving 25%annual rainfall
- Widening availability gap ‘haves’developing countries and ‘have nots’developing countries
- Rising demand +dwindling supplies-man reason over exploitation groundwater stores for irrigation
Physical factors causing water insecurity
- natural climate variability affects distribution as annual+seasonal rain
- rain greater low pressure zones+most secure, areas seasonal rain+low annual totals (Sahel)greater variation-poorer reliability supply
- ENSO exacerbates short term deficiencies water scarce areas(Sahel)
- steep relief locations more relief rain+more run-off+surface storage lakes/reservoirs especially mountainous impermeable geology may reduce insecurity
- however melting cryosphere mountains may reduce storage water+seasonal meltwater (Himalayas+Andes)increase water scarcity
- permeable chalk+porous sandstone can store huge amounts water underground-crucial reduce scarcity not susceptible evaporation loss can be accessed well/spring
- W/warming climate increase E/T-less effective precipitation(amount added+stored soil after losses)
- natural sea lvl rise(storm surges/storms/flooding) means slat water intrusions can occur at coast (salt water moves into soil+aquifers) increase fresh water scarcity
Human factors causing water insecurity (by 2030 world have 60%water it needs)
- over abstraction(rivers, lakes+groundwater) est 20%aquifers exploited, removal fresh water aquifers coastal-salt water incursions+salinisation wells,boreholes+wetlands, 2025 est withdrawals over 5000km^3/yr
- agriculture largest user 70%global+90%developing countries, 2050 need 60%more food growing pop, inefficient use water crop production-depleting aquifers,reduce river flow,degrade wildlife habitats, increase pesticide+fertiliser pollution seep groundwater, causing water logging +increase salinity (20%irrigated land suffers)
- industry demand manufacturing increase 400% 2000-50(most) mainly emerging+developing not well regulated-pollution W/industrial spillage+poor waste management causing contaminated water
- energy biofuels needs increase amounts water altho tech advancements, thermal80%+hydropower15% global electricity use lrg amounts water
- increasing pop 80m/yr est 9.1bn 2050 demand water 2x as fast, more 1/2 lives urban est 6.3bn 2050-local pressure, est 90% all waste developing countries discharged untreated rivers, lakes, oceans from inadequate water infrastructure
- increase demand-rising income+living standards w/growing middle class developing+emerging countries(unsustainable) increase meat consumption, use cars, larger homes, appliances+energy consuming devices more water consumption both production+use
Increase in demand will lead to water insecurity
- pop growth 80m/yr (9.1bn 2050)
- demand water rising 2x as fast pop growth
- 1/2pop live urban(6.3bn by 2050)->2x Africa/Asia by 2030 -high demand high density areas
- increasing econ growth manufacturing demand increase by 400% 2000-50 focus developing+emerging
- “global middle class”increase 1.8bn 2009-5bn 2030bulk Asia some Africa
- agriculture 70%demand (90%developing) 2050feeding 9.1bn require 50%increase production+ 15%increase water withdrawals unless energy efficiency savings can be shared
Why prices water varies so greatly
- transporting source-consumption Cali expensive pipes transport mountain reservoirs/rivers Colorado-coastal cities e.g. LA
- poverty+insufficient infrastructure in squatter settlements e.g. Accra, Ghana poor rely water tankers+bottled Manila 4x piped
- developing countries often free but not treated women+children African villages walk up 10km collect lose days learning+earning
- when demand>supply+scarce 2015cali poorest can’t afford supplies
- colonial govts installed limited infrastructure-urban outgrown massively
- Cuba govt subsidised water till recently so available all
- 1980s World bank+IMF gave loans developing countries so privatised provision water hope competition reduce costs but opposite e.g. Barranquilla, Colombia(rise)
- privatisation profit rise co’s+many supply reduce+ cost consumers increase e.g. 1999 Agua del Tunari took over Bolivia city Cochambamba system increase price 20%avg income-protested4days+govt cancelled contract
- varies developed Canada 80%less Ger, Ireland only started charging 2016 before 75%less UK, Denmark most expensive try cut water consumption, by 2015 many major cities taking back privatisation
Why water is so important for economies
- key all econ productivity, demand manufacturing increasing 400% 2000-50, industrial development-reduce water quality+ supply by contaminating rivers+groundwater developing (rapid industrialisation)
- energy use water intensive+increasingly used renewables (fracking, HEP), over 1/2 used generating HEP/cooling thermal nuclear power stations returned source unchanged but warmth can impact
- agriculture used 2/3rds extraction ground/surface takes 3000L produce 1kg rice, 6x produce 1kg beef
- strong link poverty+lack water
Why is water so important for societies
-unsafe spreads disease but water used personal+domestic hygiene can prevent disease transmission
-lack sanitation est 10% ‘global disease burden’ fundamental source related disease on site dry systems as well water bourne sewage combined low standards personal hygiene
-disease transmitted faecal-oral routes (major issue)thru dirty water e.g. cholera, typhoid+dysentery+Guinea worm parasite
-water related diseases high lvl morbidity affect ppls ability work+look after fam-ability escape poverty+water breeding ground vectors e.g. malaria mosquitoes
-Millennium Development Goals aimed 1/2no. ppl without safe drinking water by 2015, 2016 almost 800m still lacked treated
-WHO every $1spent water/sanitation has $7 econ benefits,every yr 433m skl days lost result dirty drinking water, women less wealthy countries avg 200m hrs collecting water every day???
-3.75m die every yr dirty water+3,400 children die every day from water bourne diseases
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Potential conflict over resulting trans-boundary(int) water sources
- how demand/supply varies along Nile Egypt dependent 95% but Rwanda+Ethiopia+others need lrg supplies develop crop irrigation, HEP+ industrial-lift out of poverty, high demand as mainly desert(Sahara)+other sources scarce, pop pressure 300m Nile basin+ exp 2x 600m 2030+increase wealth more pressure crops+HEP
- flows thru 7countries resources shared 11, 2major tributaries white+blue meet near Khartoum Sudan
- white Nile provides mere 30%flows measured Aswan dam, while catchment blue relatively small heavy monsoonal rainfall July-Sept greatest contributor lower Nile flows, much located hot, arid areas evaporation losses high entry-exit from Sudd Swamp Sudan white Nile losses up to 50%flow-early summer shortfalls Egypt+Sudan when flows from blue pre-monsoonal low pt
- CC seasonal variations key challenge susceptible major inter-annualc decadal fluctuations brought about El Niño-La Niña cycles+ future worsening droughts+ floods problematic Eritrea+Sudan
- 1929 I Nile water agreement-86%Egypt+ Sudan only 14% others+ Egypt veto any use 4 downstream nations
- 1959 II- effectively 100% Sudan+Egypt increase allocation Sudan 4-18.5bn m^3 irrigation needs, signed colonial powers GB on behalf- Ethiopia refuses recognise
- Nile Basin Initiative (NBI)emerged 1990 all 10basin (Eritrea observing) partnership W/world bank-2 action plans E Nile Program+ Equatorial Lakes Program, 2010 8/10 signed treaty:all riparian countries should =rights Nile (Sudan+Egypt didn’t)
- GERD(Grand Ethiopian Renaissance Dam)on blue, construction since 2011, 15km E border Sudan, largest HEP Africa+7th world, 2017 60%completed done 5-15yrs, Ethiopia deny neg impact downstream flow+contends increase flows Egypt by reduced evaporation Lake Nasser, angry Egyptian response demanding increase share Nile flow 66-90% est 4.8bn cost 15% Ethiopian GDP
Potential for conflict within a country Murray Darling Basin (SE Australia) SUPPLY
- 1m km^2 covering 1/7continent 20rivers e.g. Murray+ Darling
- generally dry rain about 500m-prone drought till 2011 much country decade long drought
- 2006-9rain mountainous E part(supply 40% rivers)lower any historical time, other parts basin rain deficit 1.5m below normal 1996-2008
- CC warmer temps worsen every 1degrees basin 10%more evaporation- ENSO cycle exacerbates
Potential for conflict within a country Murray Darling Basin (SE Australia) DEMAND
- most productive agricultural area country- 40%production food, 85% irrigation water, 75% water, home more 2m ppl, produces wool, cotton, wheat, cattle, dairy produce, wine etc
- recent decades studies repeatedly confirm environ health basin decline- drought, over extraction past entitlement system+ high salinity lvls+ overall poor water quality, growth blue-green algae, declining wildlife+ land degradation dismal outlook
