Physical case studies Flashcards
1
Q
Human disruption to water cycle.
A
- Amazonia
- Tropical rainforest
- South America
2
Q
Human disruption to water cycle in Amazonia context.
A
- multiple canopies of dense vegetation mean rates of interception and evapotranspiration are high.
- This causes humidity and heavy local convectional rainfall.
- An example of a self sustaining cycle where water is recycled.
- Evaporation from forest is important in sustaining regional rainfall around periphery of rainforest - important for agricultural regions of Brazil.
3
Q
Human disruption to water cycle in Amazonia impacts & problems.
A
- Research in the amazon basin suggests deforestation significantly reduces evapotranspiration and precipitation while increasing runoff and river discharge.
4
Q
Human disruption to water cycle in Amazonia facts.
A
- Tocantins River showed 25% increase in discharge between 1960 and 1997, coincident with increased deforestation.
5
Q
Drought in the Sahel context.
A
- Sahel is a vast semi-arid region across Africa which crosses 11 countries.
- Since 1960s theres been decline in annual rainfall with largest anomalies in 1980s.
- most recent severe drought occurred in 2011/12.
- There have been studies and multiple human and physical factors have been identified to be the cause.
6
Q
Causes of drought in the Sahel.
A
- In 2002 a study by the CSIRO said droughts in the late 20th century were caused by air pollution generated in Europe and North America, causing atmosphere cooling, changing the global heat budget and atmospheric circulation so that tropical rains associated with the ITCZ did not arrive.
- In 2005 a study by NOAA showed the late 20th century drought could be due to higher sea surface temperatures caused by anthropogenic climate warming. The rain bearing winds that move over the Sahel fail when the sea-surface temperatures in the tropical Atlantic ocean are warmer than average.
- The Met Office forecast that the 15/16 El Nino event would increase water stress in the western Sahel.
7
Q
Drought in the Sahel facts.
A
- 15/16 El Nino event raised temperatures in the Sahel by 2 degrees celsius, conditions similar to the 1972/73 drought.
- The Sahel region is one of the worlds highest poverty rates and lowest development levels.
- Grain production in many areas of the Sahel region in 2012 was 36 per cent down on the previous year.
8
Q
Drought in Sahel impacts.
A
- demand for food and fuel wood is accelerating and natural dryland ecosystems are being converted to farmland, which is being overcultivated and overgrazed causing desertification.
- Where effects of reduced rainfall and human pressures are combined there is reduced vegetation cover and soil moisture which may create self perpetuating droughts.
9
Q
Drought case study?
A
- The millennium drought in south-eastern Australia, 1997-2009
10
Q
Millennium drought Australia context?
A
- the millennium drought was the longest uninterrupted series of years with below average rainfall in south eastern Australia since at least 1990.
- The drought was the result of multiple physical and human causes.
- Scientists in Australia conducted simulations of global climate using a global climate model that includes different external climate drivers (natural and human).
11
Q
Millennium drought Australia causes?
A
- El Nino events in 2002-3 and 2006-7 were partly responsible
- strengthening of the high pressure belt, known as the subtropical ridge
- This ridge of high pressure blocked storm tracks (depressions), forcing them towards higher latitudes and thereby reducing frontal rainfall.
- Research indicates that there may be changes to the Hadley cell and the STR associated with anthropogenic global warming in particular
- the STR appears to have intensified as global surface temperatures increase
- In simulations, the climate model was only able to reproduce STR strengthening when human emissions of greenhouse gases were included.
- anthropogenic warming is reducing the temperature gradient between the equator and the pole, reducing energy avail for mid latitude storm systems and the polar front jet stream.
- However as with many climate change scenarios there is insufficient evidence to prove this relationship.
12
Q
Millennium drought Australia facts?
A
- annual rainfall between 1997 and 2009 was 12.4% below the 20th century average.
- research shows prevailing El Nino conditions in 2002-3 and 2006-7 explained about 2 thirds of the rainfall deficit in eastern Australia.
- strengthening of the high pressure belt/subtropical ridge accounted for 80% of the rainfall decline in south eastern Australia.
13
Q
Flooding in the UK case study context?
A
- In 2015 met office decided to name severe depressions in alphabetical order starting in November 2015.
- The 15/16 UK winter floods were caused by a series of depressions that created intense heavy rainfall and widespread flooding.
- Storm Desmond
- Storm Eva
- Storm Frank
14
Q
Storm Desmond context?
A
- brought gales and heavy rain to the UK in December 2015.
- led to localised flooding in north west England, southern Scotland, north wales and northern Ireland.
- Cumbria was the worst hit county with more than a months rainfall in one day and all the main rivers across cumbria exceeded the highest discharge levels ever recorded.
- Fronts brought prolonged and heavy rainfall as air was forced to rise across high ground of the lake district.
- Convectional and orographic precipitation was combined and together with saturated ground this created conditions for flooding.
- Existing flood defences were unable to deal with the water levels.
15
Q
Storm Desmond impacts/facts?
A
- Honister in cumbria received 341.1mm of rain in 24 hours between 4/5 december.
- The storm involved very low air pressures – 946 millibars.
- Over 5200 homes affected by flooding in cumbria and 2 deaths related to the flooding.
- 40 schools were closed in cumbria, routine appointments across NHS hospitals were cancelled.
- Lancaster uni closed early for Christmas due to power cuts which also left homes and businesses without power.
- Govt provided £50 mill to cumbria and Lancashire county council to provide money to affected households so that they could make homes more flood resilient
16
Q
Storm Eva context?
A
- brought heavy rainfall and severe flooding Christmas 2015.
- On boxing day residents in west Yorkshire and Lancashire were evacuated from homes and flooding hit Leeds, greater Manchester and York.
17
Q
Storm Eva impacts/facts?
A
- 9000 properties flooded and evacuated
- 7500 homes across north of England were affected by power cuts and there were explosions in places where gas mains were ruptured.
- irish sea ferries cancelled due to weather and main roads such as M62 were closed due to flooding.
- A number of bridges collapsed isolating communities and businesses,
- Dozens of football fixtures on boxing day were cancelled.
- Emergency measures to reduce floodwaters included the transportation of 20 water pumps and installation of 2km of temporary flood barriers in northern England.
18
Q
Storm Frank context?
A
- followed at the end of 2015, bringing storms and gales to western UK, particularly north west Scotland.
- Soils and rocks were already saturated by previous rainfall in November from Storm Abigail and Hurricane Kate.
- New hard flood defences (2010) failed in cities in northern England as they could not cope with the river flows and even held the water up prolonging the flooding.
- Academics from universities highlighted the role of deforestation and intensive agriculture in increasing sedimentation of channels and landslide risk.
- academics also called for action to manage landscapes, rivers and streams to release water slower through afforestation schemes and floodplain restoration.
19
Q
Storm Frank impacts/context?
A
- Over 300 properties were evacuated and there were power cuts and school closures.
- in early January flooding combined with freezing temperatures and snow reduced the ability of services to rescue people.
- BBC reported 1 death
20
Q
Overall impacts/facts of the UK floods 2015/16?
A
- in total 16,000 properties in England were flooded.
- Between december and January 2016 there was £24 million spent on emergency payments to households and businesses.
- 3000 families were helped into alternative accomodation and average cost of domestic property flood claim was £50,000.
- Some victims of the floods were uninsured but could seek govt support from a number of schemes and the govt provided £200 mil additional funding for flood recovery.
- Govt also committed £2.3 bil for flood management projects over the next six years.
- Accountancy firm from KPMG estimated that the total economic cost of floods would be £5 billion.
21
Q
Saltwater encroachment case study?
A
- pacific islands
22
Q
Saltwater encroachment in the pacific islands context?
A
- Many small low lying pacific islands depend on small aquifers for their freshwater supply.
- The aquifers are increasingly threatened by saltwater intrusion as a result of over abstraction, climate variability and sea level rise.
- Population growth has increased water demand resulting in increase in groundwater pumping and a consequent lowering of the water table.
- Climate variability associated with ENSO cycles is causing recurrent droughts and floods.
23
Q
Saltwater encroachment in the pacific islands facts/impacts?
A
- 35% of Samoas water supply is drawn from aquifers.
- The IPCC estimates that average global sea levels rose by 0.19m between 1901 and 2010.
- During the 1997/98 El Nino event, groundwater withdrawals in the Marshall Islands nearly tripled as a result of drought.
- Crop production depends on freshwater irrigation, making saltwater intrusion a serious threat to health, food security and livelihoods.
- This is why some island communities are relocating to other countries, such as Kiribati to New Zealand.
24
Q
transboundary water conflicts case study?
A
- river nile
25
Q
Transboundary water conflicts river nile context?
A
- the river nile is the longest river in the world and it is an international transboundary river with shared water resources.
- The Nile has 2 major tributaries, the White Nile and the Blue Nile which meet in Sudan.
- most of the river and its tributaries flow through semi-arid (Sahel) and arid (Sahara) which increases their importance as these areas are scarce of water.
- provides water for domestic, industrial and agriculture purposes and it is under pressure from rapid population growth, economic development and climate change.
- it is particularly important to Egypt and Sudan, where it is the primary water source.
- a long history of disagreements over the use of Nile.
- historic water allocation agreements favoured the downstream states of Egypt and Sudan.
- also granted Egypt veto power over construction projects on the nile.
26
Q
History of disagreements transboundary water conflicts rive nile?
A
- historic water allocation agreements favoured the downstream states of Egypt and Sudan.
- Nile agreement between Egypt and the UK (the colonial power in Sudan at that time) granted significant water allocations to Egypt and Sudan
- also granted Egypt veto power over construction projects on the nile.
- the historic agreement led to conflicts as upstream countries needed water to meet growing population and economy.
- river Nile countries signed the Nile basin initiative (NBI) to enhance cooperation over the Nile water resources.
- this initiated work on developing the cooperative framework agreement.
- countries signed the CFA agreement on sharing the river Nile water which raised strong opposition from Egypt.
- Ethiopian prime minister announced the construction of the grand Ethiopia renaissance dam on the Blue Nile, which met with an angry response from the Egyptian president who stated that Egyptians would not accept any projects.
- discussions led to a recent agreement that is expected to resolve some issues between Ethiopia and Egypt.
- Egypt, Ethiopia and Sudan met and signed an agreement on the development of the grand Ethiopia renaissance dam.
- this agreement did not resolve the broader contentious issues of sharing the Nile waters among all Nile countries, as shown by Egypt not signing the CFA.
27
Q
Transboundary water conflicts river nile facts?
A
- the 6,700km long river Nile is the longest river in the world.
- shared by 11 countries.
- 2 major tributaries, the White Nile and the Blue Nile which meet in Sudan.
- Egypt depends on the river Nile for 95% of its water needs.
- 1929 Nile agreement between Egypt and the UK.
- In 1999, the river Nile countries signed the Nile basin initiative (NBI).
- This initiated work on developing the cooperative framework agreement.
- In 2010, countries signed the CFA agreement.
- In 2011, the Ethiopian prime minister announced the construction of the grand Ethiopia renaissance dam.
- In 2015 Egypt, Ethiopia and Sudan met and signed an agreement on the development of the grand Ethiopia renaissance dam.
28
Q
conflict between water users case study?
A
- Ethiopia
29
Q
Conflict between water users in Ethiopia context?
A
- Ethiopia has an ambitious but controversial dam building programme designed to turn the country into the powerhouse of Africa fuelling economic growth.
- The programme has caused international conflict (nile case study) and internal conflict conflict such as controversy over the Gilbel Gibe III Dam.
- The Gilbel Gibe III Dam and hydroelectric power plant is on the Omo river in Ethiopia.
- The project is controversial because of its local negative environmental and social impacts.
- In june 2011 UNESCO’s world heritage committee halted construction to review its impact on Lake Turkana a natural world heritage site straddling the Kenya-ethiopia border.
- It is feared that the dam could reduce the level of Lake Turkana which could increase the salinity of the water threatening the drinking water supply, the fishing industry and the lake ecosystem.
30
Q
Conflicts between water users in Ethiopia facts/impacts?
A
- The $1.8 bil project began in 2008 and started to generate electricity in October 2015.
- Becoming the third largest hydroelectric plant in Africa.
- The environmental impact assessment was not published until 2 years after construction started.
- More than 200,000 people rely on the Omo river below the dam for subsistence farming.
- It is feared that the dam could reduce the level of Lake Turkana by up to 10 metres affecting up to 300,000 people as well as the wildlife.
- the dam will be devastating to the downstream indigenous population as it will prevent seasonal floods which subsistence farmers are dependant on to replenish dry soils for planting.
- ethnic groups such as the Mursi and Nyangatom already live in chronic hunger so the dam threatens their survival.
- Many tribes are armed to defend themselves against neighbouring tribes and there are fears that water shortages could cause violent conflict.
- Those supporting the dam construction argue that artificial floods can be released from the reservoir and irrigation projects are planned for cotton and sugar cane plantations in the lower Omo valley.
- However critics claim that these plantations will only benefit Ethiopian state owned companies and there are reports of human rights violations by Ethiopian army against locals who oppose the sugar plantations.
31
Q
Water supply schemes case study?
A
- China’s South-North water transfer.
32
Q
China’s South-North case study context?
A
- North china is suffering from water scarcity and the problem is most acute in the Hai basin where Beijing is located.
- The water table under the capital is falling and water quality is poor due to pollution.
- China has designed a hard-engineering solution which is the largest basin water transfer scheme in the world.
- the project aims to provide North China with freshwater from the south via 2 routes.
- however the project has raised a number of SEE concerns.
- Critics feel that with more effective water management, North-china could be self-sufficient without water transfer from the south.
- Rainwater harvesting and waste-water recycling could meet demand in cities and agriculture losses could be reduced by lining irrigation canals with concrete.
33
Q
China’s South-North case study impacts/facts?
A
Impacts:
- Social = more than 300,000 people displaced during construction of central route as water levels had to be raised by 13m.
- Economic = expensive with $80bil costs + maintenance.
- Environmental = water transfer doesn’t solve pollution and inefficient agricultural, industrial and urban use in the north of China + extracting water from the Yangtze drainage basin will reduce discharge impacting ecosystems.
- 80% of chinas water is in the south.
- The water table under the capital has fallen by 300 metres since 1970’s.
- water quality is poor in up to 60% of river water.
- the project has capacity to deliver 25 bil metres cubed of freshwater per year.
- the 2 routes each cover 1,000km, a third route remains in planning stage.
34
Q
sustainable water management schemes case study?
A
- singapore
35
Q
sustainable water management schemes in Singapore case study context?
A
- Singapore receives abundant rainfall however because of limited land for collection and storage of rainwater, the tropical climate causes high evaporation rates leading to water scarcity.
- Singapore’s national water agency have invested into research for a diversified water supply comprising local catchment water, imported water, recycled water and desalinated water.
- Local catchment water involves collecting rainwater through a network of drains, canals, rivers, storm-water collection ponds and reservoirs before it is treated to supply drinking water.
- Singapore currently import water from Malaysia.
- Recycled water also known as NEWater is high grade water produced from water that is treated and further purified using advanced membrane technologies and ultraviolet disinfection, making it ultra-clean and safe to drink.
36
Q
sustainable water management schemes in Singapore case study facts?
A
- Singapore is a city state with an area of 710 square kilometres and a population of 5.6million.
- Receives 2400mm rainfall per year.
- Singapore has an agreement until 2061 to import water from Malaysia
- Singapore’s 4 new plants can meet up to 30% of the nation’s current water needs by 2060 it aims to meet 55% of water demand.
37
Q
Smart Irrigation case study?
A
- China
- Australia
38
Q
Smart Irrigation in China and Australia case study context?
A
- Smart irrigation provides crops with a suboptimal water supply causing mild stress during crop growth stages that are less sensitive to moisture deficiency.
- This technique has been found to conserve water without significant reduction in yield.
- Controlled irrigation such as drip feed ensures that water goes directly into the soil next to the roots of crops which prevents evaporation losses.
39
Q
Smart Irrigation in China and Australia case study facts?
A
- A 6 year study of winter wheat production on the north china plain showed water savings of 25% or more through smart irrigation, combined with acceptably high yields and net profits.
- In Australia, regulated smart irrigation of fruit trees increased water productivity by 60% with a gain in fruit quality and no loss in yield.
40
Q
Rainwater harvesting jars case study?
A
- Uganda
41
Q
Rainwater harvesting jars in Uganda case study context?
A
- Wateraid is an international non-governmental organisation that raises funds to improve access to safe water.
- Local builders have been trained in the construction of rainwater harvesting jars.
- They are designed to collect rainwater from roofs and store water for drier periods.
- The objective has been to help the community construct on-site water supplies close to home, removing the need to travel long distances across difficult terrain to collect water.
- The jars are long lasting and once constructed provide a stable water source.
42
Q
Rainwater harvesting jars in Uganda case study facts?
A
- An example of Wateraid’s work can be seen in Kitayita village in Uganda where 3,000 people lack access to safe water.
- rainwater harvesting jars are made from locally available materials and have a capacity of 1,500 litres.
43
Q
Integrated river management case study?
A
- Colorado river
44
Q
Integrated river management case study context?
A
- Precipitation in the Colorado river basin varies, but has recently been prone to drought conditions due to climate change.
- Other challenges include increased urbanisation, population growth and agricultural needs for irrigation water.
- Even in the 1920s it was recognised that the growing western states needed water, especially southern California.
- In 1992 states agreed a compact and the basin was divided into upper (source areas) and lower (demand areas) sections for management purposes and water was allocated by state.
- Sometimes there has not been enough water to meet all allocations and this has led to disputes that still exist today.
- In 1990 the lower basin US states used their full allocation for the first time making the issue worse, but with drier conditions and reservoir levels falling there simply is not enough water to meet demands.
- Individual states have been forced to look for alternatives.
- All of the 21st century has seen discussions of solutions but without a new agreement being reached.
45
Q
Integrated river management case study facts?
A
- The Colorado river is 2,330km and flows through a basin of area 637,000km^2.
- 97% of the basin is in USA and 3% in Mexico.
- The source is in the rocky mountains, it flows through the semi arid areas of the Colorado plateau and has its mouth at the Gulf of California in Mexico.
- In 1956 a comprehensive development plan was developed to cover river regulation, HEP production, water rights and irrigation.
- There are 29 dams and numerous diversion projects now in existence.
- Environmental protection laws have complicated management, such as the grand canyon protection act 1992.
- Individual states have been forced to look at alternatives for example Nevada has tried negotiating for extra water allocation (especially for las vegas).
- California has introduced irrigation restrictions and is investigating desalination.
- Arizona established a water banking authority in 1996 with the aim of using its water share efficiently and storing surpluses in aquifers within the state (creating a water bank).
46
Q
rules on water resources case study?
A
- The Berlin Rules
47
Q
The Berlin Rules on Water Resources case study context?
A
- The berlin rules on water resources were approved by the international law association in 2004.
- The rules outline international law on freshwater resources, within a nation or crossing international boundaries, and they replace the earlier 1966 Helsinki rules.
- There are 9 water management principles that apply to all countries including national and internationally shared waters.
- ongoing conflicts between River Nile countries show the difficulties in implementing the Berlin Rules and achieving effective water sharing treaties.
48
Q
What are the Berlin Rules on Water Resources?
A
- Participatory water management – the public have a right to be involved in decision making.
- Coordinated use – surface water and groundwater resources to be managed to maximise the availability and reliability of water supplies.
- Integrated management – all components of the drainage basin to be considered, such as vegetation, watercourses, settlements and all stakeholders.
- Sustainability – economic, social and environmental needs to be met now and in the future.
- Minimisation of environmental harm – such as pollution.
- Cooperation over shared water resources – between regions in a country or between countries.
- Equitable utilisation of shared water resources – all groups and communities to receive a fair share.
- Avoidance of transboundary harm – control of actions upstream.
- Equitable participation – all countries or players to have equal status.
