Section C - The Water Cycle and Water Insecurity Flashcards
What is the water cycle?
The cycle of processes by which water circulates between the earth’s oceans, atmosphere, and land
Stores in the water cycle - Hydrosphere, oceans - what percentage of the Earth’s water oceans contain?
The oceans contain 97% of Earth’s water
Processes of the water cycle - What is evaporation?
Heat from the sun causes water to evaporate
Processes of the water cycle - What is condensation?
Water vapour rises and condenses as clouds
Processes of the water cycle - What is advection?
Winds move clouds through the atmosphere
Processes of the water cycle - What is percipitation?
Water droplets fall from clouds as drizzle, rain, snow or ice
Processes of the water cycle - What is snowmelt?
Snow and ice accumulate, later melting back into liquid water or turning into vapour
Processes of the water cycle - What is surface runoff?
Water flows above ground as runoff, forming streams, rivers, swamps, ponds and lakes
Processes of the water cycle - What is interception?
Plants intercept percipitation falling from the sky
Processes of the water cycle - What is infiltration/percolation?
Water is soaked into the ground, flows below it, and seeps back out enriched in minerals
What is the % of total water, % of freshwater and residence time of oceans?
% of total water = 97%
% of fresh water = 0%
Residence time = 3600 years
What is the % of total water, % of freshwater and residence time of icecaps?
% of total water = 1.9%
% of fresh water = 68%
Residence time = 15,000 years depending on size
What is the % of total water, % of freshwater and residence time of groundwater?
% of total water = 1.1%
% of fresh water = 30%
Residence time = Up to 10,000 years for deep groundwater, 100-200 years for shallow ground water
What is the % of total water, % of freshwater and residence time of rivers and lakes?
% of total water = 0.01%
% of fresh water = 1.2%
Residence time = 2 weeks to 10 years
What is the % of total water, % of freshwater and residence time of soil moisture?
% of total water = 0.01%
% of fresh water = 0.05%
Residence time = 2-50 weeks
What is the % of total water, % of freshwater and residence time of atmospheric moisture?
% of total water = 0.001%
% of fresh water = 0.04%
Residence time = 10 days
Amazonia case study - average temp and climate
- 27 degrees C average temp in the amazon
- Warm and wet climate all year round
Amazonia case study - What % of global freshwater per day come from Amazon river discharge?
15%
Between 2000 and 2007 what was the Amazon’s rate of deforestation per year?
20,000 km2 per year
Brazil pollution stats (global polluter ranking and % of emissions used for land use change)
- Brazil is the 6th largest polluter in the world
- 75% of their emissions are from deforestation and land-use change
What are the impacts of human activity in the Amazon on the water cycle? (3)
- Extreme rainfall events could lead to more flash flooding events
- Overall reduction in river discharge
- 15% less water can be held in the soil - more easily eroded - faster rates of runoff
Have there been attempts to reduce deforestation in Brazil? (2)
- In 2008 the Zero Deforestation Campaign was proposed – this later became the Amazon Fund
- However, under Bolsonaro deforestation rates have risen significantly again, further threatening the Amazonia
Sahel case study - Type of hazard, when
- Drought
- Happening now
Sahel case study - Why is it happening and what are four human factors?
Changing rainfall patters caused droughts that have lasted for over a year - this has caused vegetation cover to wither and die, leaving soil exposed below – human factors are overgrazing, overpopulation, overcultivation, and human enhanced climate change
Sahel case study - Social impacts - What will happen to people’s land and what will this lead to?
If desertification continues to occur people will lose land that could be used for farming and livestock so they won’t be able to provide for their families leading to poverty and famine
Sahel case study - Economic impacts
The loss of arable land means less opportunities for people to sell and market food which would be the main source of income for people in these developing nations
Sahel case study - Environmental impacts
Loss of habitats due to desertification will mean a less diverse ecosystem and potentially endangering animals as humans will have to use other lands to make up for land lost to the drought – drought also dries up rivers
Sahel case study - Responses (changes in agriculture)
Encouraging farmers to grow drought resistant crops, using drip irrigation systems to reduced water usage
Australia case study - Type of hazard, when
- Drought
- 2015-16
Australia case study - What led to it and when?
Particularly strong El Nino wind led to harsh drought between 2015-16
Australia case study - Social impacts (4)
- Crop failure
- Water restrictions
- Wine industry affected by lack of water and risk of fire
- Rural residents found it more difficult to access clean drinking water and safe food
Australia case study - Economic impacts (what did fewer crops and livestock lead to)
With fewer crops and livestock, Australia had to import more food, this increased the price of food across the whole country
Australia case study - Environmental impacts (destruction, what happened in May?)
Wildfires caused by drought destroyed vegetation and animals’ habitats, drought replaced by heavy rains in May which led to flooding, largest recorded mangrove dieback, less energy generated through hydroelectric power
Australia case study - Immediate responses
People using less water, products such as dishwashers are rated for water efficiency, more and more homes are using water saving devices
Australia case study - Long term responses - What is Australia investing in?
Australia is investing in large desalination plants which turn seawater into safe drinking water – costly but will help protect against droughts
UK case study - Type of hazard, when
- Flood
- Summer 2007
UK case study - What led to it and what did this cause?
Exceptionally heavy rainfall in the summer of 2007 caused extensive flooding in the UK, particularly in East Yorkshire and the Midlands
UK case study - Social impacts (2)
- 13 deaths
- Mental health symptoms among individuals who reported flooding in their homes
UK case study - Economic impacts (cost of damages)
£6.5 billion in damages
UK case study - Environmental impacts (3)
- Water quality degradation
- Soil erosion
- Increased green house gas emissions
UK case study - Immediate responses
Fast response from emergency rescue teams as well as the 4x4 response group who helped blue light services (emergency services)
UK case study - Long term responses (How much money did gov contribute to flood defs and the affected councils)
Gov would increase the spending on risk management and flood defences by £200 million to £800 million by 2010-2011 as well as give £46 million to the councils affected
Bangladesh case study - Type of hazard, when
- Flood
- May 2022 to June 2022
Bangladesh case study - What led to it?
Deadly floods hit North-eastern India and Bangladesh which was caused by Monsoon rains
Bangladesh case study - Social impacts (4) (affected, killed, land, disease)
- Over 9 million in both countries affected
- 300 killed
- 53,000 hectares of land submerged
- 20,000 cases of waterborne disease as of July 2022 leading to 75 deaths
Bangladesh case study - Economic impacts (2)
- Floods submerged 53,000 hectares of land
- Damage to agricultural livestock = $230 million
Bangladesh case study - Environmental impacts
- Excess water drains into rivers and underground aquifers, water is also polluted with fertilisers
- Constant flooding creates erosion, water logging, and salination of the soil
Bangladesh case study - Immediate responses (how many people taken to how many shelters?)
475,000 people taken to around 1600 shelters in a combined effort of emergency services and the Army
Bangladesh case study - Long-term responses (What did Bangladesh do and how much did the WB contribute?)
Rebuilding of infrastructure after the damage from flooding and $500 million World Bank financing to help Bangladesh improve disaster preparedness for floods
What % of water on earth is stored as fresh water?
2.5%
What % of fresh water is readily accessible surface water?
1%
EQ3 case study - California - What happened up until 2016 and from 2017
California experienced several years of drought conditions up until 2016 but from 2017 experienced major storms and an abundance of precipitation
During this period, how many wildfires have occurred and acres of farm land been lost in California?
1000 wildfire
640,000 acres of farm land lost
What is the normal winter scenario for California?
In normal winters, southwest winds from the ocean deliver water but these winds have failed in California
What is the cause of these failed winds in California?
Not really linked to climate change, human enhanced or otherwise - instead, La Nina has produced drier conditions in the West, as opposed to El Nino which would have caused above average rainfall
EQ3 case study - The Nile - Situation in Uganda (pop rise and impacts of this)
Ugandan pop expected to triple by 2050 to 97 million - raises demand for water and food from the Nile - gov wants to build dams on the Nile to protect against this issue but this would restrict the flow of water to countries such as Sudan and Egypt
EQ3 case study - The Nile - Situation in Ethiopia - (pop rise and its impacts)
In Ethiopia, pop expected to reach 150 million by 2050 – raises demand for water and food from the Nile – similar to Uganda, Ethiopia wants to build dams and keep more of the Nile’s water for itself – brings it into conflict with Egypt and Sudan
EQ3 Case study - The Nile - Situation in Sudan
Sudan is facing a problem of desertification and a falling water table – Sudanese gov wants to expand the use of irrigation systems to increase food supply which will mean taking more water from the Nile – again brings it into conflict with the others
EQ3 - The Nile - Situation in Egypt
Egypt pop expected to rise to 122 million in 2050 – rise in demand for water and food from the Nile – Egypt relies on the Nile for 90% of its water supply – the Nile’s water is used to irrigate farmland on either side of the river allowing crips to be grown for domestic use and for export
EQ3 - Case study - The Three Gorges Dam - When was construction complete?
Construction on the Three Gorges Dam was completed in 2008
EQ3 - Case study - The Three Gorges Dam - What does the Yangtze river drain?
The Yangtze river drains an area of 1.8 million km2 – home to over 400 million people or about a third of China’s pop
EQ3 - Case study - The Three Gorges Dam - What is the objective of the Three Gorges Dam?
Aims to reduce flooding, improve navigation for shipping and generate electricity through hydropower - also helps control the level of water in the Yangtze during times of flooding
EQ3 - Case study - The Three Gorges Dam - How many people does the Three Gorges Dam benefit/how much farm land it protects?
Benefits over 15 million people living in areas that are at high-risk of flooding, whilst also protecting 25000 hectares of farmland
EQ3 Case study - The Three Gorges Dam - Negatives of the Three Gorges Dam
Yangtze River is becoming more and more polluted from shipping and waste discharge
EQ3 Case study - Aral Sea - Reasons for depletion of the Aral Sea?
Soviet gov in 1918 deciding that the two rivers that fed the Aral sea would be diverted to irrigate the desert in order to grow crops
EQ3 Case study - Aral Sea - What did the loss of water lead to?
Led to the sea shrinking and the water evaporating, causing the sea to start shrinking in the early 1960s - this led to fewer fish being able to survive in the sea due to the increasing pollution and saline in the sea – this in turn led to fewer jobs in the area for fishermen which led to people moving away in search of new jobs
EQ3 Case study - Aral Sea - Other impacts (sea port, biodiversity)
Led to a severe reduction in the Aral Sea port - many plants and animals that used to live in the sea have migrated away or died
EQ3 Case study - Aral Sea - What has been done to combat the loss of water?
In 2005, the Kazaks built the Kokaral Dam which has led to partial recovery in the North Aral Sea
EQ3 - Case study - Kielder Water Transfer - Background
The North East of England is highly variable in how much precipitation it receives - to ensure enough precipitation, the Kielder Water Transfer Scheme was built
EQ3 - Case study - Kielder Water Transfer - What is the Kielder Water Transfer itself?
A water management scheme designed to store water for the North East of England - built in the North West of England, a high precipitation zone
EQ3 Case study - Kielder Water Transfer - How much water does Kielder receive in comparison to Newcastle?
Kielder receives 1700mm of water per year – Newcastle only receives 644mm per year
EQ3 Case study - What happens to the water from Kielder?
The water from Kielder is then pumped through a pipeline to areas in North-East England that need it
