Lecture 1: Introduction to global water resources Flashcards
Define freshwater resources
Stores than can be renewed within a reasonale time frame e.g. river flows
Define non-renewable freshwater resources
the stores that will not be replenished within a reasonable time frame e.g. deep groundwater in the sahara
Refresh your knowledge of the hydrological cycle
The circulation of water fluxes between sotres of water. This drives the renewal of freshwater
What resources of water are potentially useful
- glaciers and snow (FW)
- Wetlands
- Soil moisture
- Lake (FW)
- Groundwater (FW)
- rivers (FW)
examples of renewable freshwater resources in the hydrological cycle
Glaciers and snow
river
lake
examples of non-renewable freshwater resources in the hydrological cycle
Glaciers and snow
groundwater
Explain motivation 1
Water is required for life
- paramount societal importance
- while the overall amount of water is fixed, population is increasing and therefore having an understanding of water and its storage and movement is key to our survival and will likely dictate how and where we will live in the future.
Explain motivation 2: water is a common but finite resource
water is the most common substance on earth and constantly renews itself through evaporation and rainfall. 97% of the worlds water is in the oceans and most of what is left is locked up in ice caps and glaciers, etc., leaving just 1% of the worlds water available for human consumption.
Explain motivation 3: water enables and constrains all human activity
This water must not satisfy domestic use, but also industry, agriculture, energy and so on. The worlds water needs, however, are not being satisfied. Over a billion people still have no decent water supply and 2.4billion do not have proper sanitation; over 60% of global ill health can be linked to water. Population is increasing and demands are changing.
explain motivation 4: development is dependent on access to water
Without tackling these problems, little progress can be made on other development issues (e.g. children required by the family to fetch water several miles cannot attend school, sick oeple cannot work, infant mortality will remain very high.
explain motivation 5: geopolitical stability is related to water resources stability
Because this all has significant geopolitical implications for countries and their relative power or success in the world, ‘water wars’ between countries competing for scarce water resources has become a serious international concern.
How much water do we need and how much is available?
1,700m3/person/year
25,000m3/person/year (FAO)
but reneable freshwater resources are not evenly distributed globally
using LA as an example, describe the disconnect between supply and demand
LOS Angeles recieves approximately 15 inches of precipitation per year, which amounts to approximately 90 gallons/day/person. The average user in LA however requires approximately 200gallons/days, an amount that cannot be met by local supply
what is the big challen in SSA?
Kenya: over 17million kenyans still lack access to safe water. this has a huge impact on health and infant mortality.
Renewable freshwater resources are also not evenly distributed over time: soil moisture over africa shows large variability that differs greatly between regions.
how do hydrological hazards create further challenges?
flooding (Northwest england floods december 2015).
(Atacama Desert, northern chile, March 2015): The 2015 Northern Chile floods were a series of mudflows that affected much of northern Chile, product of flash floods from different rivers due to unseasonal heavy rains in the area, causing severe damage in several towns of the Antofagasta, Atacama and Coquimbo regions.[1][2] Flooding in Chile and Peru resulted from an unusual cold front which moved across the Andes, bringing heavy rainfall to the region
2010/2011 horn of african drought and famine
- 12.4million people in need of humanitarian across the region
- Dabaab refugee cample: over 1,000 arrivals each day, 25% of new arrivals children are malnourished
- Dollo Ado refugee camp: 54,000 new arrivals in 2011, 50% of new arrivals children are malnourished
describe the food-energy-water nexus links between water to other essential sectors
…
water importances to agriculture
agricultural irrigation: much of which occurs in some of the areas of lowest precipitation (e.g. central valleys of california, southeast spain, Israel).
such mismathces in distrbution of water availability and use is not uncommon throughout the world and necessitates a significant amount of water resources engineering to move water from where it is plentiful to where it is needed.
Sometimes the source of water is unsustainable.
Water importance to energy production
energy production is highly dependent on water.
- hydroelectric power generation requires huge amounts of water to drive turbines and is often most feasible source of energy in many developing countries
thermo electric power generation requires huge amounts of cooling water which is succeptible to drought and high water temps
water importance to health
Many global health challenges are related to water because of poor sanitation, lack of access to clean water, under-developed water management.
- over 60% of global ill health can be linked to water
- for example, many communicable diseases are water-borne or involve a transmitter that reies on water for its life cycle
What global pressures are impacting water availability
- population growth and changing demographic
- agricultural demand and changing diets
- climate change
- Unsustainable water use
- we live in a connected world
where are the regional hotspots of water shortages
asia saudi middle east northern africa horn of africa central america
what are the economics of water
the need for water and its scarcity implies economic value, hence making water of high economic interest.
water scarcity and floods/droughts link to many other things such as conflict, civilisation collpase (Mayan civilisation which flourished up to about 900AD in the southeast of Mexico) (global warming contributed to syrias 2011 uprising, scientists claim
the world economic forum: commited to improving the state of the world.
what are the global risks related to the water crisis
a significant decline in the available quantity and quality of fresh water resulting in harmful effects on human health and/ or economic activity.
- disease spread
- deflation
- extreme weather
- interstate conflict
- large scale involuntry migration
etc.
really good diagram on slides about the most likely global risks by 2016
not
what are the top five global risks of highest concern for the next 18months and 10 years
18 months
- large scale involtary migration (52%)
- state collpase or crisis (27.9%)
- interstate conflict (26.3%)
- unemployment or undermeployment (26%)
- failure of national governance (25.2%)
10 years
- water crisis (39.8%)
- failure of climate change mitigation and adapatation (36.7%)
- xtreme weather events (26.5%)
- food crises (25.2%)
- profound social instability (23.3%)
how do we solve these challenges?
SDGs
6: clean water and sanitation
explain goal 6: ensure access to water and sanitation for all
Drinking water
• 2.6 billion people gained access to improved drinking water sources since 1990 (76-91%)
• But 663 million people are still without
• At least 1.8 billion people globally use a source of drinking water that is fecally contaminated
Sanitation
• 2.4 billion people lack access to basic sanitation services, such as toilets or latrines
• Each day, nearly 1,000 children die due to preventable water and sanitation-related
diarrhoeal diseases
Water Scarcity
• water scarcity affects more than 40 per cent of the global population and is projected to rise.
• Over 1.7 billion people are currently living in river basins where water use exceeds recharge
• Hydropower is the most important and widely-used renewable source of energy and as of 2011,
represented 16 per cent of total electricity production worldwide
• Floods and other water-related disasters account for 70 per cent of all deaths related to natural
disasters
what are the goals for goal 6:
• Achieve universal and equitable access to safe and affordable drinking water for all
• Achieve access to adequate and equitable sanitation and hygiene for all and end open
defecation, paying special attention to the needs of women and girls and those in vulnerable
situations
• Improve water quality by reducing pollution, eliminating dumping and minimizing release of
hazardous chemicals and materials, halving the proportion of untreated wastewater and
substantially increasing recycling and safe reuse globally
• Substantially increase water-use efficiency across all sectors and ensure sustainable
withdrawals and supply of freshwater to address water scarcity and substantially reduce the
number of people suffering from water scarcity
• Implement integrated water resources management at all levels, including through
transboundary cooperation as appropriate
• Protect and restore water-related ecosystems, including mountains, forests, wetlands, rivers,
aquifers and lakes
• Expand international cooperation and capacity-building support to developing countries in waterand
sanitation-related activities and programmes, including water harvesting, desalination, water
efficiency, wastewater treatment, recycling and reuse technologies
• Support and strengthen the participation of local communities in improving water and sanitation
management
what is the water challenge in india?
India’s population is growing, and its water
supplies are not keeping pace.
India is considering an ambitious plan to
link the majority of its major river basins
through a vast network of canals, diverting
billions of litres from the country’s more
water-rich river basins to those that are
water-deprived.
what is the water challenge in gaza?
Geography, politics, and war combine to make the Gaza Strip
a worst-case scenario for water-resource planners
• 1.5 M people in the Gaza strip and reliant on the coastal
aquifer
• Increasing pollution from agriculture and sewage and
saltwater intrusion
• Rainfall provides some recharge of the aquifer but much
evaporates and much is drawn from wells, and a little is
needed to push back the seawater, but over-pumping
means the aquifer is unsustainable
• Kidney disease (high salt levels) and blue
baby syndrome (high nitrogen levels)
• Plans for state-of-the-art wastewater
treatment and desalination plants but
security concerns and sanctions
what is the water challenge in china?
The Chinese government has begun a massive engineering project to divert water from three southern rivers to the parched north— with unknown consequences… The problem: The government estimates that 96 million Chinese, mostly in northern rural areas, now lack sufficient drinking water, and this will only get worse. The symptoms: Problems such as In the Beijing region, the groundwater table has steadily receded from an average of 10 meters below the surface in 1975 to 35 meters in 2005. Solution: South-North Water Transfer Scheme Potential unintended consequences: impacts from pollution transfer and on ecosystems
what is hydrology?
the study of water
In particular, hydrologic science is a branch of geoscience that
aims to diagnose and predict:
1) the spatial and temporal characteristics of water in its
various storage reservoirs (terrestrial, atmospheric, oceanic)
2) the corresponding fluxes of water between these reservoirs.
what is the importance of hydrological sciences?
Engineering Design: To design engineering structures (e.g. reservoirs,
irrigation schemes) we need to know how much water there is and how it
varies in time (e.g. from year to year)
- Mitigation of Hazards: To provide early warning of hydrological disasters
(e.g. floods and droughts) we need to know the risk of events (based on
past historic records of events and computer prediction models that
forecast the likelihood of an event happening in the future).
- Fundamental Science: Water plays a key role in the Earth system as a
whole, including weather and climate processes, landscape evolution,
and biogeochemical processes.
