Water scarcity

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Water scarcity occurs  when there are not enough water resources to meet existing water needs.

General

People on every continent are affected by water scarcity. In 2019, the World Economic Forum declared water scarcity and its implications as the greatest threat of the coming decade. Water scarcity has various effects. This generally includes the underfunding of the existing demand, but also the economic competition for water quantity and quality. Other effects include disputes among consumers, the irreversible decrease in groundwater and further negative effects on the environment. Two thirds of the world's population live under severe water scarcity for at least one month a year. Half a billion people suffer from water scarcity throughout the year, as do half of the world's largest cities .

Only 0.014% of all water on earth is both fresh water and easily accessible. Although 97% is salt water and just under 3% is in hard-to-reach places such as the polar ice caps, there is in principle enough water to meet the needs of mankind. Nevertheless, a global water crisis is expected, exacerbated by climate change , unequal distribution of resources and the strong increase in demand for water. Global demand is expected to exceed the amount of available water by 40% within 15 years.

There is a global scarcity of water because fresh water is unevenly distributed geographically and seasonally. The main reasons for an increase in water scarcity worldwide are the growing world population , rising standard of living , changing consumer behavior and the expansion of artificial irrigation in agriculture . Other reasons are climate change , for example changes in weather behavior ( droughts and floods ), deforestation , increasing water pollution as well as wasteful water consumption and inefficient water supply. Thus, water scarcity is often caused by anthropogenic interventions in the water cycle .

Water scarcity changes depending on how much water is physically available. However, influencing factors such as economic policy, planning and water management are very important. Water scarcity usually worsens as economic developments advance, but if the causes are identified early and the influencing factors are correctly forecast, it can be averted or weakened.

supply and demand

Global use of water resources. Source: 2016 FAO data.
Global water consumption 1900–2025 by region, in billions m ^ 3 per year.

In total, there are 14,000 cubic kilometers of easily accessible fresh water supplies on earth. This includes surface water in rivers and lakes , but also groundwater . Of this total supply, 5,000 cubic kilometers are used and reused by mankind. Theoretically, there is enough fresh water to supply a world population of 7 billion people or even a population increase to 9 billion people. But due to the unequal geographical distribution and, in particular, the unevenly high consumption of water, there is a water shortage in some regions of the world where large parts of the world population live.

Water scarcity as a result of overexploitation is mainly caused by agriculture and, in this case, mainly by animal husbandry , but also by industry . People in industrialized countries use around ten times more water than people in developing countries . A large part of this consumption is caused by indirect water consumption, for example in the agricultural or industrial production of consumer goods. Due to the globalization of production chains, a lot of water is used in emerging and developing countries to produce goods that are consumed in industrialized countries.

Physical and economic water scarcity

Water scarcity is divided into two types:

  • Physical / natural water scarcity
  • Economic water scarcity

Physical water scarcity occurs when the demand for water exceeds the natural resources of a region. Economic water scarcity arises from poor management of the available water resources. According to the United Nations Development Program, poor water management is more common than a lack of natural resources as the cause of water scarcity. Most countries and regions that are suffering from water scarcity actually have sufficient deposits but do not have the necessary know-how or the technology to make it accessible to the population. Arid regions often suffer from physical water scarcity. But it can also arise when resources are overexploited, for example for hydroelectric power plants, dams or artificial irrigation. Effects of physical water scarcity are, for example, environmental degradation, consumption of groundwater or waste.

Economic water scarcity is caused by a lack of investment in infrastructure and technology to distribute fresh water from rivers, reservoirs and other water sources. A quarter of the world population is affected by economic water scarcity. Due to the lack of infrastructure, affected people are often forced to travel very long distances to get to water sources. In addition, this water is then often polluted by household sewage or runoff from agriculture. Large parts of Africa suffer from economic water scarcity; the scarcity of water could be greatly reduced here by expanding the infrastructure. Economically or politically weak sections of the population are often affected by water scarcity. The consumption in industrialized countries is 200-300 liters per day, in developing countries around 10 liters. Various international organizations recommend a minimum of 20 liters, which should be within one kilometer of the household. In countries with water scarcity, there is speculation about water as a resource.

Water as a human right

In the Meatu Region of Simiyu , Tanzania (Africa), water is often extracted from holes dug in dry river beds. This task is mostly taken over by girls, which is why they do not receive any schooling.

The UN Committee on Economic, Social and Cultural Rights agreed that water security contains five basic elements. This includes the right to sufficient, safe, adequate, physically accessible and affordable water for personal and private consumption.

At the United Nations Millennium Summit , access to safe drinking water was identified as one of the Millennium Development Goals . The MDG 7 sat halving the proportion of people without sustainable access to safe drinking water from 65 percent to 32 percent as a target.

Impact on the environment

Water scarcity has many negative effects on the environment. The overexploitation of the resource, as is common in the case of water scarcity, leads to salinization , eutrophication and the loss of floodplains and marshland . In addition, water scarcity makes river management and the recovery of urban rivers difficult.

Over the past hundred years, more than half of the world's wetlands or moorlands have disappeared or been destroyed. However, these areas are important because they are not only the habitat of many species, but also areas where rice and other foods are grown. They also act as natural filters, protecting surrounding areas from flooding and storms. Freshwater lakes such as the Aral Sea in Central Asia have also been affected. The formerly largest freshwater lake has lost more than 58,000 square kilometers of its former 68,000 square kilometers in area within 30 years and is increasingly saline.

Land subsidence, the gradual subsidence of areas, is another effect of water scarcity. The United States Geological Survey estimated that more than 17,000 square miles in 45 US states have been affected by subsidence, most of it from pumping out of groundwater. In some regions, like Houston , the land has sunk more than nine feet.

Climate change

The World Bank stated that climate change will lead to changes in the availability and use of water. This will increase water scarcity and increase uncertainties in sectors that consume large amounts of water. Pumping water out of aquiferous layers and fossil water leads to an increase in the total amount of water in the hydrosphere that is available for evaporation and transport processes. This increases the water vapor and the cloud cover. These are the largest absorbers of infrared radiation in the earth's atmosphere. The increase in water in the atmosphere changes the climate. However, it is not yet possible to precisely estimate the complicated processes and effects.

Measurement of water scarcity

GEO-2000 estimate for 2025, 25 African countries will suffer from water scarcity or water stress.

Hydrologists determine the extent of water scarcity by quantifying the ratio of population to available water. The amount of available water resources per year is related to the total population of a country or region. The Falkenmark water stress indicator, for example, says that a region or a country suffers from water scarcity (English: waterstress ) when the annual water resources fall below 1,700 cubic meters per person per year. With values ​​between 1,000 and 1,700 cubic meters per person per year, periodic or spatially limited water shortages can occur. If less than 1,000 cubic meters per person per year are available, there is a water scarcity. If the amount falls below 500 cubic meters per person and year, one speaks of a water emergency . The World Food Organization has estimated that 1.9 billion people will be living in countries or regions with absolute water scarcity in 2025. Two thirds of the world's population will suffer from water scarcity.

Water crisis

If there is not enough drinking water for a certain population, then one speaks of a water crisis . The United Nations and other world organizations are concerned about a global water crisis. The World Food Organization (FAO) said in 2003 that there are no water crises, but that measures must be taken to prevent them.

In 2012 in Sindh , Pakistan, people stood in line to get clean water.

Effects of the water crisis

Globally, the water crisis is manifesting itself in different ways:

  • Inadequate access to safe drinking water for 884 million people.
  • In 2006 the UNICEF / Who Joint Monitoring Program report (JMP) found insufficient access to sanitation for 2.5 billion people, which often leads to water pollution .
  • Overuse of groundwater, which leads to poor harvests.
  • Overuse of water pollution that destroyed biodiversity.
  • Regional conflicts over resources up to armed conflicts.

Waterborne pathogens caused by a lack of sanitation and hygiene are a leading cause of death worldwide. For children under five, they are the main cause. According to the World Bank in 2007, 88 percent of the diseases spread over water are caused by unsafe drinking water, inadequate sanitation and poor hygiene.

A 2006 report by the United Nations focused on the main causes of the water crisis: "There is enough water. Water shortages are often caused by mismanagement, corruption, a lack of appropriate institutions, bureaucratic inertia and a lack of investment in both human capital and infrastructure." Official data show a strong correlation between GDP and access to safe drinking water.

Economists have often said that the water crisis was also caused by a lack of property rights, government regulation, and subsidies that brought prices down. Thus the prices for water were too low and thus the consumption too high.

outlook

Wind and solar systems, like in this village in northwest Madagascar, can lead to clean drinking water.

The construction of sewage treatment plants and reducing the overuse of groundwater are obvious solutions to the problem. However, wastewater treatment is very capital-intensive, which is why the application of the technology is not possible in some regions. In addition, the rapid population growth makes the fight against water scarcity difficult. Furthermore, sewage treatment plants require know-how and human capital in their operation and development, which, even if plants were built from outside, would not be available in all regions in order to keep the plants permanently in operation.

Reducing the overuse of groundwater is mostly politically unpopular and has negative economic effects on agriculture. In addition, the strategy leads to a reduction in agricultural production, which is not possible given the population growth.

A realistic strategy for developing countries would be to introduce basic wastewater treatment, or at least systems like cesspools. They should also conduct a thorough study of wastewater generation to minimize its impact on drinking water and the ecosystem. Developed countries should better share their technologies, such as inexpensive wastewater treatment methods and modeling of water transport. On a personal level, people in developed countries can switch their consumption to use less water and contribute less to global water consumption. Both industrialized and developing countries should be more careful to protect their ecosystems, especially wetlands and floodplains. This would protect the natural water cycle, which contributes to better water quality for people.

A number of low-tech and locally applicable solutions are being pursued by some companies. For example, water is boiled using solar energy or distilled at temperatures below 100 ° C. More and more solutions for filtering purification of local water are also being developed. The Bedouins in the city of Dahab in Egypt, for example, have installed the AquaDania WaterStillar , which uses a two-square-meter solar collector to distill 40 to 60 liters of water a day. This prevents plastic bottles that contribute significantly to pollution from being used for transport.

Worldwide experience in dealing with water scarcity

It is believed that the likelihood of conflict increases when the change within a water catchment exceeds the capabilities of the existing institutions to deal with it. Although water conflicts are often related to existing local tensions, history shows that there is far more cooperation in dealing with the resource than armed conflicts.

The key to this are strong institutions and partnerships. The Indus River Commission and the Indus Water Treaty between India and Pakistan are important mechanisms for resolving conflicts, despite the hostilities between the two states. They provide a framework for discussions, inspections and the exchange of data. The Mekong Committee has been functioning since 1957, including during the Vietnam War. In contrast, conflicts arise when these institutions are missing, as was the case in Egypt when a dam was planned. Nevertheless, today there is no global institution for the management of cross-border water catchment areas. When institutions are founded, it is through ad hoc amalgamation of existing organizations. The Mekong Committee was initiated by an alliance between UNICEF and the US Bureau for Land Reclamation. The formation of strong international institutions seems to be a good step in the right direction - it encourages early intervention and prevents costly resolution of conflicts.

A common feature of almost all resolved conflicts is a “needs approach” rather than a “rights approach”. Irrigated land, the population and the technical requirements of projects define the need. One example of this is the Jordan , in which a water agreement was concluded based on the needs of the rivers. In South Asia, the division of the Ganges is geared towards the irrigation needs of Bangladesh . A needs-based, regional approach that seeks to meet the needs of individuals so that the minimum is reached is preferable. This prevents parties from concentrating only on their own interests and seeing agreements as zero-sum games; both parties see more advantages in the long term from the cooperation of both interests.

The Blue Peace Network, developed by the Strategic Foresight Group of the governments of Switzerland and Sweden, offers a unique regulatory structure that combines the sustainable management of water with cooperation for peace. The best possible use is made of water resources and the chances for peace are increased. The Blue Peace approach has proven effective, for example in the Middle East or the Nile. NGOs also play a role as they work to increase access to clean water.

See also

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  1. ^ The Global Risks Report 2019. In: Insight Report. World Economic Forum, 2019, accessed November 26, 2019 .
  2. ^ Coping with water scarcity. An action framework for agriculture and food security . Food and Agriculture Organization of the United Nations . 2012. Accessed December 31, 2017.
  3. ↑ AY Hoekstra, MM Mekonnen: Four billion people facing severe water scarcity . American Association for the Advancement of Science , February 12, 2016. (Accessed December 30, 2017).
  4. ↑ 4 billion people face water shortages, scientists find . World Economic Forum. February 17, 2016. Retrieved December 30, 2017.
  5. ↑ How do we prevent today's water crisis becoming tomorrow's catastrophe? . World Economic Forum. March 23, 2017. Accessed December 30, 2017.
  6. ↑ Global Water Shortage Risk Is Worse Than Scientists Thought . Huffingtonpost.com. February 15, 2016. Retrieved December 29, 2017.
  7. ↑ Water, bron van ontwikkeling, makes en conflict . NCDO, Netherlands. January 8, 2012. Accessed January 1, 2018.
  8. ↑ SL Postel, GC Daily, PR Ehrlich, Human appropriation of renewable fresh water. Science 271 : 785-788 (1996).
  9. ↑ HHG Savenije, Water scarcity indicators; the deception of the numbers. Physics and Chemistry of the Earth B 25 , 199-204 (2000).
  10. ↑ CJ Vörösmarty, P. Green, J. Salisbury, RB Lammers, Global water resources: Vulnerability from climate change and population growth. Science 289 , 284-288 (2000)
  11. ^ AE Ercin, AY Hoekstra, Water footprint scenarios for 2050: A global analysis. Environment International 64 , 71-82 (2014).
  12. ^ Water Scarcity. Threats . In: WWF . 2013. Retrieved October 20, 2013.
  13. ↑ Why freshwater shortages will cause the next great global crisis . The Guardian . March 8, 2015. Accessed January 3, 2018.
  14. ↑ United Nations Development Program (2006). Human Development Report 2006: Beyond Scarcity-Power, Poverty and the Global Water Crisis . Basingstoke, United Kingdom: Palgrave Macmillan.
  15. ^ Water scarcity, risk and vulnerability . Retrieved December 2, 2014.
  16. ^ Sergiusz Prokurat: Drought and water shortages in Asia as a threat and economic problem . In: Journal of Modern Science . , Józefów2015, pp. 235–250. Retrieved August 5, 2016.
  17. ↑ Lack of safe water and sanitation in schools affects children's learning - and their lives Unicef ​​Published April 5, 2010. Retrieved January 3, 2018
  18. ↑ Impact of water scarcity on girls education The Citizen , Tanzania, published November 14, 2017. Retrieved January 3, 2018
  19. ^ Water Scarcity Index - Vital Water Graphics . Retrieved October 20, 2013.
  20. ↑ Lawrence, JE, CPW Pavia, S. Kaing, HN Bischel, RG Luthy, and VH Resh: Recycled Water for Augmenting Urban Streams in Mediterranean-climate Regions: A Potential Approach for Riparian Ecosystem Enhancement . In: Hydrological Sciences Journal . 59, 2014, pp. 488-501.
  21. ↑ Texas Water Report: Going Deeper for the Solution ( Memento of February 22, 2014 in the Internet Archive ) Texas Comptroller of Public Accounts. Retrieved October 2, 2014.
  22. ^ The World Bank, 2009 Water and Climate Change: Understanding the Risks and Making Climate-Smart Investment Decisions . Pp. 21-24. Retrieved October 24, 2011.
  23. ↑ GEO-2000 overview overview . Retrieved September 22, 2016.
  24. ↑ Annual water availability per person (Falkenmark indicator). Retrieved November 26, 2019 .
  25. ↑ : SarbeswarHaldar1, Prasenjit Saha perspective A Geographical - Identifying the Causes of Water Scarcity in Purulia, West Bengal, India. In: IOSR Journal of Environmental Science, Toxicology and Food Technology. August 2015, p. 43 , accessed on November 26, 2019 (English).
  26. ^ Water Scarcity - One of the greatest challenges of our time. Retrieved November 26, 2019 .
  27. ↑ Freshwater: lifeblood of the planet . Peopleandplanet.net (November 11, 2002). Retrieved August 27, 2013.
  28. ↑ World water crisis spoken by corruption, repression: UN report . Un.org. February 20, 2006. Retrieved March 10, 2011.
  29. ^ UN World Summit on Sustainable Development . Published by the NRDC at the World Summit for Sustainable Development, August 29, 2002.
  30. ^ "No global water crisis - but may developing countries will face water scarcity" . FAO.org. March 12, 2003.
  31. ↑ Updated Numbers: WHO-UNICEF JMP Report 2008 . Unicef.org. Retrieved March 10, 2011.
  32. ^ Water is Life - Groundwater drawdown . Academic.evergreen.edu. Retrieved March 10, 2011.
  33. ^ All About: Water and Health , CNN. December 18, 2007. 
  34. ^ Water, a shared responsibility. The United Nations World Water Development Report 2 , 2006
  35. ↑ Public Services . Gapminder video.
  36. ↑ Segerfeldt, Fredrik (August 25, 2005), "Private Water Saves Lives" , Financial Times .
  37. ^ Zetland, David (August 1, 2008) "Running Out of Water" . aguanomics.com
  38. ^ Zetland, David (July 14, 2008) "Water Crisis" . aguanomics.com
  39. ↑ Mansfield, Barry (December 1, 2012), "The man who can change fire into water" ( February 11, 2015 memento in the Internet Archive ), easyJet Traveler .
  40. ^ Turkish Review , March 2013
  41. ↑ Water management and peace promotion in the Middle East ( Memento from September 26, 2013 in the web archive archive.today ). Deza.admin.ch. Retrieved November 24, 2015.
  42. ^ Blue Peace: New Solution for Averting Water Wars in the Nile Basin - Yahoo Finance. September 28, 2013, accessed November 26, 2019 .