Cloud seeding

From Wikipedia, the free encyclopedia

https://en.wikipedia.org/wiki/Cloud_seeding 

 

Cloud seeding can be done by ground generators, planes, or rockets

 

This image explaining cloud seeding shows a substance - either silver iodide or dry ice - being dumped onto the cloud, which then becomes a rain shower. The process shown in the upper-right is what is happening in the cloud and the process of condensation upon the introduced material.

Cloud seeding is a type of weather modification that aims to change the amount or type of precipitation that falls from clouds by dispersing substances into the air that serve as cloud condensation or ice nuclei, which alter the microphysical processes within the cloud. The usual intent is to increase precipitation (rain or snow), but hail and fog suppression are also widely practised in airports where harsh weather conditions are experienced.

Cloud seeding also occurs due to ice nucleators in nature, most of which are bacterial in origin.

Methodology

The most common chemicals used for cloud seeding include silver iodide, potassium iodide and dry ice (solid carbon dioxide). Liquid propane, which expands into a gas, has also been used. This can produce ice crystals at higher temperatures than silver iodide. After promising research, the use of hygroscopic materials, such as table salt, is becoming more popular.

When cloud seeding, increased snowfall takes place when temperatures within the clouds are between −4 and 19 °F (−20 and −7 °C). Introduction of a substance such as silver iodide, which has a crystalline structure similar to that of ice, will induce freezing nucleation.

In mid-altitude clouds, the usual seeding strategy has been based on the fact that the equilibrium vapor pressure is lower over ice than over water. The formation of ice particles in supercooled clouds allows those particles to grow at the expense of liquid droplets. If sufficient growth takes place, the particles become heavy enough to fall as precipitation from clouds that otherwise would produce no precipitation. This process is known as "static" seeding.

Seeding of warm-season or tropical cumulonimbus (convective) clouds seeks to exploit the latent heat released by freezing. This strategy of "dynamic" seeding assumes that the additional latent heat adds buoyancy, strengthens updrafts, ensures more low-level convergence, and ultimately causes rapid growth of properly selected clouds.

Cloud seeding chemicals may be dispersed by aircraft or by dispersion devices located on the ground (generators or canisters fired from anti-aircraft guns or rockets). For release by aircraft, silver iodide flares are ignited and dispersed as an aircraft flies through the inflow of a cloud. When released by devices on the ground, the fine particles are carried downwind and upward by air currents after release.

An electronic mechanism was tested in 2010, when infrared laser pulses were directed to the air above Berlin by researchers from the University of Geneva. The experimenters posited that the pulses would encourage atmospheric sulfur dioxide and nitrogen dioxide to form particles that would then act as seeds.

Effectiveness

Whether cloud seeding is effective in producing a statistically significant increase in precipitation is still a matter of academic debate, with contrasting results depending on the study in question, and contrasting opinion among experts.

A study conducted by the National Academy of Sciences failed to find statistically significant support for the effectiveness of cloud seeding. Based on the report's findings, Stanford University ecologist Rob Jackson said: "I think you can squeeze out a little more snow or rain in some places under some conditions, but that's quite different from a program claiming to reliably increase precipitation." Data similar to that of the NAS study was acquired in a separate study conducted by the Wyoming Weather Modification Pilot Project. However, whereas the NAS study concluded that "it is difficult to show clearly that cloud seeding has a very large effect," the WWMPP study concluded that "seeding could augment the snowpack by a maximum of 3% over an entire season."

In 2003 the US National Research Council (NRC) released a report stating, "...science is unable to say with assurance which, if any, seeding techniques produce positive effects. In the 55 years following the first cloud-seeding demonstrations, substantial progress has been made in understanding the natural processes that account for our daily weather. Yet scientifically acceptable proof for significant seeding effects has not been achieved".

A 2010 Tel Aviv University study claimed that the common practice of cloud seeding to improve rainfall, with materials such as silver iodide and frozen carbon dioxide, seems to have little if any impact on the amount of precipitation. A 2011 study suggested that airplanes may produce ice particles by freezing cloud droplets that cool as they flow around the tips of propellers, over wings or over jet aircraft, and thereby unintentionally seed clouds. This could have potentially serious consequences for particular hail stone formation.

However, Jeff Tilley, director of weather modification at the Desert Research Institute in Reno, claimed in 2016 that new technology and research has produced reliable results that make cloud seeding a dependable and affordable water supply practice for many regions. Moreover, in 1998 the American Meteorological Society held that "precipitation from supercooled orographic clouds (clouds that develop over mountains) has been seasonally increased by about 10%." 

Despite the mixed scientific results, cloud seeding was attempted during the 2008 Summer Olympics in Beijing to coax rain showers out of clouds before they reached the Olympic city in order to prevent rain during the opening and closing ceremonies. Whether this attempt was successful is a matter of dispute, with Roelof Bruintjes, who leads the National Center for Atmospheric Research's weather-modification group, remarking that "we cannot make clouds or chase clouds away." 

Impact on environment and health

With an NFPA 704 health hazard rating of 2, silver iodide can cause temporary incapacitation or possible residual injury to humans and other mammals with intense or chronic exposure. However, there have been several detailed ecological studies that showed negligible environmental and health impacts. The toxicity of silver and silver compounds (from silver iodide) was shown to be of low order in some studies. These findings likely result from the minute amounts of silver generated by cloud seeding, which are about one percent of industry emissions into the atmosphere in many parts of the world, or individual exposure from tooth fillings.

Accumulations in the soil, vegetation, and surface runoff have not been large enough to measure above natural background. A 1995 environmental assessment in the Sierra Nevada of California and a 2004 independent panel of experts in Australia confirmed these earlier findings.

"In 1978, an estimated 3,000 tonnes of silver were released into the US environment. This led the US Health Services and EPA to conduct studies regarding the potential for environmental and human health hazards related to silver. These agencies and other state agencies applied the Clean Water Act of 1977 and 1987 to establish regulations on this type of pollution."

Cloud seeding over Kosciuszko National Park—a biosphere reserve—is problematic in that several rapid changes of environmental legislation were made to enable the trial. Environmentalists are concerned about the uptake of elemental silver in a highly sensitive environment affecting the pygmy possum among other species as well as recent high level algal blooms in once pristine glacial lakes. Research 50 years ago and analysis by the former Snowy Mountains Authority led to the cessation of the cloud seeding program in the 1950s with non-definitive results. Formerly, cloud seeding was rejected in Australia on environmental grounds because of concerns about the protected species, the pygmy possum. Since silver iodide and not elemental silver is the cloud seeding material, the claims of negative environmental impact are disputed by peer-reviewed research as summarized by the international Weather Modification Association.

History of cloud seeding

Cessna 210 with cloud seeding equipment

Louis Gathmann in 1891 suggested shooting liquid carbon dioxide into rain clouds to cause them to rain. During the 1930s, the Bergeron–Findeisen process theorized that supercooled water droplets present while ice crystals are released into rain clouds would cause rain. While researching aircraft icing, General Electric (GE)'s Vincent Schaefer and Irving Langmuir confirmed the theory. Schaefer discovered the principle of cloud seeding in July 1946 through a series of serendipitous events. 

Following ideas generated between him and Nobel laureate Langmuir while climbing Mt Washington in New Hampshire, Schaefer, Langmuir's research associate, created a way of experimenting with supercooled clouds using a deep freeze unit of potential agents to stimulate ice crystal growth, i.e., table salt, talcum powder, soils, dust, and various chemical agents with minor effect. Then one hot and humid July 14, 1946, he wanted to try a few experiments at GE's Schenectady Research Lab

He was dismayed to find that the deep freezer was not cold enough to produce a "cloud" using breath air. He decided to move the process along by adding a chunk of dry ice just to lower the temperature of his experimental chamber. To his astonishment, as soon as he breathed into the deep freezer, he noted a bluish haze, followed by an eye-popping display of millions of microscopic ice crystals, reflecting the strong light rays from the lamp illuminating a cross-section of the chamber. He instantly realized that he had discovered a way to change super-cooled water into ice crystals. The experiment was easily replicated, and he explored the temperature gradient to establish the −40 °C limit for liquid water.

Within the month, Schaefer's colleague, the atmospheric scientist Dr. Bernard Vonnegut was credited with discovering another method for "seeding" super-cooled cloud water. Vonnegut accomplished his discovery at the desk, looking up information in a basic chemistry text and then tinkering with silver and iodide chemicals to produce silver iodide. Together with Professor Henry Chessin, SUNY Albany, a crystallographer, he co-authored a publication in Science and received a patent in 1975. Both methods were adopted for use in cloud seeding during 1946 while working for GE in the state of New York.

Schaefer's method altered a cloud's heat budget; Vonnegut's altered formative crystal structure, an ingenious property related to a good match in lattice constant between the two types of crystal. (The crystallography of ice later played a role in Vonnegut's brother Kurt Vonnegut's novel Cat's Cradle). The first attempt to modify natural clouds in the field through "cloud seeding" began during a flight that began in upstate New York on 13 November 1946. Schaefer was able to cause snow to fall near Mount Greylock in western Massachusetts, after he dumped six pounds of dry ice into the target cloud from a plane after a 60-mile easterly chase from the Schenectady County Airport.

Dry ice and silver iodide agents are effective in changing the physical chemistry of super-cooled clouds, thus useful in augmentation of winter snowfall over mountains and under certain conditions, in lightning and hail suppression. While not a new technique, hygroscopic seeding for enhancement of rainfall in warm clouds is enjoying a revival, based on some positive indications from research in South Africa, Mexico, and elsewhere. The hygroscopic material most commonly used is table salt. It is postulated that hygroscopic seeding causes the droplet size spectrum in clouds to become more maritime (bigger drops) and less continental, stimulating rainfall through coalescence. From March 1967 until July 1972, the US military's Operation Popeye cloud-seeded silver iodide to extend the monsoon season over North Vietnam, specifically the Ho Chi Minh Trail. The operation resulted in the targeted areas seeing an extension of the monsoon period an average of 30 to 45 days. The 54th Weather Reconnaissance Squadron carried out the operation to "make mud, not war".

One private organization that offered, during the 1970s, to conduct weather modification (cloud seeding from the ground using silver iodide flares) was Irving P. Krick and Associates of Palm Springs, California. They were contracted by Oklahoma State University in 1972 to conduct a seeding project to increase warm cloud rainfall in the Lake Carl Blackwell watershed. That lake was, at that time (1972–73), the primary water supply for Stillwater, Oklahoma and was dangerously low. The project did not operate for a long enough time to show statistically any change from natural variations.

An attempt by the United States military to modify hurricanes in the Atlantic basin using cloud seeding in the 1960s was called Project Stormfury. Only a few hurricanes were tested with cloud seeding because of the strict rules set by the scientists of the project. It was unclear whether the project was successful. Hurricanes appeared to change slightly in structure, but only temporarily. The fear that cloud seeding could potentially change the course or power of hurricanes and negatively affect people in the storm's path stopped the project.

Two federal agencies have supported various weather modification research projects, which began in the early-1960s: The United States Bureau of Reclamation (Reclamation; Department of the Interior) and the National Oceanic and Atmospheric Administration (NOAA; Department of Commerce). Reclamation sponsored several cloud seeding research projects under the umbrella of Project Skywater from 1964 to 1988, and NOAA conducted the Atmospheric Modification Program from 1979 to 1993. The sponsored projects were carried out in several states and two countries (Thailand and Morocco), studying both winter and summer cloud seeding. From 1962 to 1988 Reclamation developed cloud seeding applied research to augment water supplies in the western US. The research focused on winter orographic seeding to enhance snowfall in the Rocky Mountains and Sierra Nevada, and precipitation in coast ranges of southern California. In California Reclamation partnered with the California Department of Water Resources (CDWR) to sponsor the Serra Cooperative Pilot Project (SCPP), based in Auburn CA, to conduct seeding experiments in the central Sierra. The University of Nevada and Desert Research Institute provided cloud physics, physical chemistry, and other field support. The High Plains Cooperative Pilot Project (HIPLEX), focused on convective cloud seeding to increase rainfall during the growing season in Montana, Kansas, and Texas from 1974 to 1979. In 1979, the World Meteorological Organization, and other member-states led by the Government of Spain conducted a Precipitation Enhancement Project (PEP) in Spain, with inconclusive results due probably to location selection issues. Reclamation sponsored research at several universities including Colorado State University, Universities of Wyoming, Washington, UCLA, Utah, Chicago, NYU, Montana, Colorado and research teams at Stanford, Meteorology Research Inc., and Penn State University, and South Dakota School of Mines and Technology, North Dakota, Texas A&M, Texas Tech, and Oklahoma. Cooperative efforts with state water resources agencies in California, Colorado, Montana, Kansas, Oklahoma, Texas, and Arizona assured that the applied research met state water management needs. The High Plains Cooperative Pilot Project also engaged in partnerships with NASA, Environment Canada, and the National Center for Atmospheric Research (NCAR). More recently, in cooperation with six western states, Reclamation sponsored a small cooperative research program called the Weather Damage Modification Program, from 2002–2006.

In the United States, funding for research has declined in the last two decades. However, the Bureau of Reclamation sponsored a six-state research program from 2002–2006, called the "Weather Damage Modification Program". A 2003 study by the United States National Academy of Sciences urges a national research program to clear up remaining questions about weather modification's efficacy and practice.

In Australia, the Commonwealth Scientific and Industrial Research Organisation (CSIRO) conducted major trials between 1947 and the early-1960s:

• 1947 – 1952: CSIRO scientists dropped dry ice into the tops of cumulus clouds. The method worked reliably with clouds that were very cold, producing rain that would not have otherwise fallen.
• 1953 – 1956: CSIRO carried out similar trials in South Australia, Queensland and other states. Experiments used both ground-based and airborne silver iodide generators.
• Late-1950s and early-1960s: Cloud seeding in the Snowy Mountains, on the Cape York Peninsula in Queensland, in the New England District of New South Wales, and in the Warragamba catchment area west of Sydney.

Only the trial conducted in the Snowy Mountains produced statistically significant rainfall increases over the entire experiment.

An Austrian study to use silver iodide seeding for hail prevention ran during 1981–2000, and the technique is still actively deployed there.

Asia

China

The largest cloud seeding system is in the People's Republic of China. They believe that it increases the amount of rain over several increasingly arid regions, including its capital city, Beijing, by firing silver iodide rockets into the sky where rain is desired. There is even political strife caused by neighboring regions that accuse each other of "stealing rain" using cloud seeding. China used cloud seeding in Beijing just before the 2008 Olympic Games in order to have a dry Olympic season. In February 2009, China also blasted iodide sticks over Beijing to artificially induce snowfall after four months of drought, and blasted iodide sticks over other areas of northern China to increase snowfall. The snowfall in Beijing lasted for approximately three days and led to the closure of 12 main roads around Beijing. At the end of October 2009 Beijing claimed it had its earliest snowfall since 1987 due to cloud seeding.

India

In India, cloud seeding operations were conducted during the years 1983, 1984–87,1993-94 by Tamil Nadu Govt due to severe drought. In the years 2003 and 2004 Karnataka government initiated cloud seeding. Cloud seeding operations were also conducted in the same year through US-based Weather Modification Inc. in the state of Maharashtra. In 2008, there were plans for 12 districts of state of Andhra Pradesh.

Indonesia

In Jakarta, cloud seeding was used to minimize flood risk in anticipation of heavy floods in 2013, according to the Agency for the Assessment and Application of Technology.

Islamic Republic of Iran

IRGC AF has been taking a cloud seeding contract project through UAVs in 10 Iranian provinces.

Israel

Israel has been enhancing rain in convective clouds since the 1950s. The practice involves emitting silver iodide from airplanes and ground stations. The seeding takes place only in the northern parts of Israel.

Kuwait

To counter drought and a growing population in a desert region, Kuwait is embarking on its own cloud seeding program, with the local Environment Public Authority conducting a study to gauge its viability locally.

United Arab Emirates

The United Arab Emirates is one of the first countries in the Persian Gulf region to use cloud seeding technology. It adopted the latest technologies available on a global level, using sophisticated weather radar to monitor the atmosphere of the country around the clock.

In the UAE, cloud seeding is being conducted by the weather authorities to create artificial rain. The project, which began in July 2010 and cost US$11 million, has been successful in creating rain storms in the Dubai and Abu Dhabi deserts.

The UAE has an arid climate with less than 100mm per year of rainfall, a high evaporation rate of surface water and a low groundwater recharge rate. Although rainfall in the UAE has been fluctuating over the last few decades in winter season, most of that occurs in the December to March period. During the summer months, the prevailing Indian Monsoon drought effect leads to a build-up of cumulus clouds especially along the mountainous terrain in the eastern UAE.

The UAE cloud-seeding Program was initiated in the late 1990s. By early 2001 the Program was being conducted in cooperation with the National Center for Atmospheric Research (NCAR) in Colorado, USA, the Witwatersrand University in South Africa and the US Space Agency, NASA.

In 2005, the UAE launched the UAE Prize for Excellence in Advancing the Science and Practice of Weather Modification in collaboration with the World Meteorological Organization (WMO). This prize was thereafter reshaped into the International Research Program for Rain Enhancement Science.

It subsequently became the UAE Research Program for Rain Enhancement Science in January 2015. The Program for Rain Enhancement Science is an initiative of the United Arab Emirates Ministry of Presidential Affairs. It is overseen by the UAE National Center of Meteorology & Seismology (NCMS) based in Abu Dhabi. Among its key goals are advancing the science, technology and implementation of rain enhancement and encouraging additional investments in research funding and research partnerships to advance the field, increasing rainfall and ensuring water security globally.

The UAE now has more 75 networked automatic weather stations distributed across the UAE, 7 air quality stations, a sophisticated Doppler weather radar network of five stationary and one mobile radar, and six Beechcraft King Air C90 aircraft for cloud seeding operations. Natural salts such as potassium chloride and sodium chloride are used in these operations. At present, the UAE mostly seed with salt particles in the eastern mountains on the border to Oman to raise levels in aquifers and reservoirs.

Forecasters and scientists have estimated that cloud seeding operations can enhance rainfall by as much as 30 to 35 per cent in a clear atmosphere, and by up to 10 to 15 per cent in a turbid atmosphere.

A total of 187 missions were sent to seed clouds in the UAE in 2015, with each aircraft taking about three hours to target five to six clouds at a cost of $3,000 per operation.

A cloud seeding experiment in January 2020 resulted in flooding.

Southeast Asia

In Southeast Asia, open-burning haze pollutes the regional environment. Cloud seeding has been used to improve the air quality by encouraging rainfall.

On 20 June 2013, Indonesia said it will begin cloud-seeding operations following reports from Singapore and Malaysia that smog caused by forest and bush fires in Sumatra have disrupted daily activities in the neighboring countries. On 25 June 2013, hailstones were reported to have fallen over some parts of Singapore. Despite NEA denials, some believe that the hailstones are the result of cloud seeding in Indonesia.

In 2015 cloud seeding was done daily in Malaysia since the haze began in early-August.

Thailand started a rain-making project in the late-1950s, known today as the Royal Rainmaking Project. Its first efforts scattered sea salt in the air to catch the humidity and dry ice to condense the humidity to form clouds. The project took about ten years of experiments and refinement. The first field operations began in 1969 above Khao Yai National Park. Since then the Thai government claims that rainmaking has been successfully applied throughout Thailand and neighboring countries. On 12 October 2005 the European Patent Office granted to King Bhumibol Adulyadej the patent EP 1 491 088 Weather modification by royal rainmaking technology. The budget of the Department of Royal Rainmaking and Agricultural Aviation in FY2019 was 2,224 million baht.

Sri Lanka

Cloud seeding was used due to the low amount of rain causing low power generation from hydro in March 2019

North America

United States

In the United States, cloud seeding is used to increase precipitation in areas experiencing drought, to reduce the size of hailstones that form in thunderstorms, and to reduce the amount of fog in and around airports. In the summer of 1948, the usually humid city of Alexandria, Louisiana, under Mayor Carl B. Close, seeded a cloud with dry ice at the municipal airport during a drought; quickly 0.85 inches of rainfall occurred.

Cloud seeding is occasionally used by major ski resorts to induce snowfall. Eleven western states and one Canadian province (Alberta) have ongoing weather modification operational programs. In January 2006, an $8.8 million cloud seeding project began in Wyoming to examine the effects of cloud seeding on snowfall over Wyoming's Medicine Bow, Sierra Madre, and Wind River mountain ranges.

In Oregon, Hood River seeding was used by Portland General Electric to produce snow for hydro power in 1974-1975. The results were substantial, but caused an undue burden on the locals who experienced overpowering rainfall causing street collapses and mud slides. PGE discontinued its seeding practices the following year.

The US signed the Environmental Modification Convention in 1978 which banned the use of weather modification for hostile purposes.

Canada

During the sixties, Irving P. Krick & Associates operated a successful cloud seeding operation in the area around Calgary, Alberta. This utilized both aircraft and ground-based generators that pumped silver iodide into the atmosphere in an attempt to reduce the threat of hail damage. Ralph Langeman, Lynn Garrison, and Stan McLeod, all ex-members of the RCAF's 403 Squadron, attending the University of Alberta, spent their summers flying hail suppression. The Alberta Hail Suppression Project is continuing with C$3 million a year in funding from insurance companies to reduce hail damage in southern Alberta.

Cessna 441 Conquest II used to conduct cloud-seeding flights in the Australian state of Tasmania

Europe

Bulgaria

Bulgaria operates a national network of hail protection, silver iodide rocket sites, strategically located in agricultural areas such as the rose valley. Each site protects an area of 10 sq. km, the density of the site clusters is such that at least 2 sites will be able to target a single hail cloud, initial detection of hail cloud formation to firing of the rockets is typically 7–10 minutes in its entire process with a view to seed the formation of much smaller hailstones, high in the atmosphere that will melt before reaching ground level.

Data collated since the 1960s suggests huge agricultural sector losses are avoided yearly with the protection system, unseeded the hail will flatten entire regions, with seeding this can be reduced to minor leaf damage from the smaller hailstones that failed to melt.

France and Spain

Cloud seeding began in France during the 1950s with the intent of reducing hail damage to crops. The ANELFA project consists of local agencies acting within a non-profit organization. A similar project in Spain is managed by the Consorcio por la Lucha Antigranizo de Aragon. The success of the French program was supported by insurance data; that of the Spanish program in studies conducted by the Spanish Agricultural Ministry.

Russia

The Soviet Union created a specifically designed version of the Antonov An-30 aerial survey aircraft, the An-30M Sky Cleaner, with eight containers of solid carbon dioxide in the cargo area plus external pods containing meteorological cartridges that could be fired into clouds. Soviet military pilots seeded clouds over the Belorussian SSR after the Chernobyl disaster to remove radioactive particles from clouds heading toward Moscow. Currently, An-26 is also used for cloud seeding. At the July 2006 G8 Summit in St. Petersburg, President Putin commented that air force jets had been deployed to seed incoming clouds so they rained over Finland. Rain drenched the summit anyway. In Moscow, the Russian Airforce tried seeding clouds with bags of cement on June 17, 2008. One of the bags did not pulverize and went through the roof of a house. In October 2009, the Mayor of Moscow promised a "winter without snow" for the city after revealing efforts by the Russian Air Force to seed the clouds upwind from Moscow throughout the winter.

Germany

In Germany civic engagement societies organize cloud seeding on a region level. A registered society maintains aircraft for cloud seeding to protect agricultural areas from hail in the district Rosenheim, the district Miesbach, the district Traunstein (all located in southern Bavaria, Germany) and the district Kufstein (located in Tyrol, Austria).

Cloud seeding is also used in Baden-Württemberg, a federal state particularly known for its winegrowing culture. The districts of Ludwigsburg, Heilbronn, Schwarzwald-Baar and Rems-Murr, as well as the cities Stuttgart and Esslingen participate in a program to prevent the formation of hailstones. Reports from a local insurance agency suggest that the cloud seeding activities in the Stuttgart area have prevented about 5 million euro in damages in 2015 while the project's annual upkeep is priced at only 325.000 euro. Another society for cloud seeding operates in the district of Villingen-Schwenningen.

Slovenia

In Slovenia oldest aeroclub: Letalski center Maribor carries air defense against hail. The Cessna 206 is equipped with external aggregates and flares for flying. The purpose of the defense is to prevent damage to farmland and cities. They have been carrying out defense since 1983. Silver iodide is used as a reagent. The base is at Maribor Edvard Rusjan Airport.

United Kingdom

Project Cumulus was a UK government initiative to investigate weather manipulation, in particular through cloud seeding experiments, operational between 1949 and 1952. A conspiracy theory has circulated that the Lynmouth flood of 1952 was caused by secret cloud seeding experiments carried out by the Royal Air Force. However, meteorologist Philip Eden has given several reasons why "it is preposterous to blame the Lynmouth flood on such experiments".

Australia

In Australia, summer activities of CSIRO and Hydro Tasmania over central and western Tasmania between the 1960s and the present day appear to have been successful. Seeding over the Hydro-Electricity Commission catchment area on the Central Plateau achieved rainfall increases as high as 30 percent in autumn. The Tasmanian experiments were so successful that the Commission has regularly undertaken seeding ever since in mountainous parts of the State.

In 2004, Snowy Hydro Limited began a trial of cloud seeding to assess the feasibility of increasing snow precipitation in the Snowy Mountains in Australia. The test period, originally scheduled to end in 2009, was later extended to 2014. The New South Wales (NSW) Natural Resources Commission, responsible for supervising the cloud seeding operations, believes that the trial may have difficulty establishing statistically whether cloud seeding operations are increasing snowfall. This project was discussed at a summit in Narrabri, NSW on 1 December 2006. The summit met with the intention of outlining a proposal for a 5-year trial, focusing on Northern NSW.

The various implications of such a widespread trial were discussed, drawing on the combined knowledge of several worldwide experts, including representatives from the Tasmanian Hydro Cloud Seeding Project however does not make reference to former cloud seeding experiments by the then-Snowy Mountains Authority, which rejected weather modification. The trial required changes to NSW environmental legislation in order to facilitate placement of the cloud seeding apparatus. The modern experiment is not supported for the Australian Alps.

In December 2006, the Queensland government of Australia announced a $7.6 million in funding for "warm cloud" seeding research to be conducted jointly by the Australian Bureau of Meteorology and the United States National Center for Atmospheric Research. Outcomes of the study are hoped to ease continuing drought conditions in the states South East region.

In March 2020, scientists from the Sydney Institute of Marine Science Centre and Southern Cross University trialled marine cloud seeding off the coast of Queensland, Australia, with the aim to protect Great Barrier Reef from coral bleaching and dieoff during marine heatwaves. Using two high-pressure turbines, the team sprayed microscopic droplets of saltwater into the air. These then evaporate leaving behind very small salt crystals, which water vapour clings to, creating clouds that reflect the sun more effectively.

Africa

In Mali and Niger, cloud seeding is also used on a national scale.

In 1985 the Moroccan Government started with a Cloud seeding program called 'Al-Ghait'. The system was first used in Morocco in 1999; it has also been used between 1999 and 2002 in Burkina Faso and from 2005 in Senegal. For this program two aircraft were equipped with special instruments:

An unknown Beech King Air; which holds cloud physics and seeding equipment RMAF's Alpha Jet No 245; which only holds the seeding equipment.

Conspiracy theories

Cloud seeding has been the focus of many theories based on the belief that governments manipulate the weather in order to control various conditions, including global warming, populations, military weapons testing, public health, and flooding.

Water scarcity

From Wikipedia, the free encyclopedia

https://en.wikipedia.org/wiki/Water_scarcity 

 

Baseline water stress per region: the ratio of total annual water withdrawals to total available annual renewable supply, accounting for upstream consumptive use

 

Water stress per country

 

Global physical and economic water scarcity

 

Children fetch water from a muddy stream in a rural area during dry season. The water is taken back home and undergoes filtration and other treatments before usage.

 

Water Scarcity, Jaffna

Water scarcity is the lack of fresh water resources to meet the standard water demand. Water scarcity can also be caused by droughts, lack of rainfall, or pollution. This was listed in 2019 by the World Economic Forum as one of the largest global risks in terms of potential impact over the next decade. It is manifested by partial or no satisfaction of expressed demand, economic competition for water quantity or quality, disputes between users, irreversible depletion of groundwater, and negative impacts on the environment. Two-thirds of the global population (4 billion people) live under conditions of severe water scarcity at least 1 month of the year. Half a billion people in the world face severe water scarcity all year round. Half of the world's largest cities experience water scarcity.

A mere 0.014% of all water on Earth is both fresh and easily accessible. Of the remaining water, 97% is saline and a little less than 3% is difficult to access. Technically, there is a sufficient amount of freshwater on a global scale. However, due to unequal distribution (exacerbated by climate change) resulting in some very wet and some very dry geographic locations, plus a sharp rise in global freshwater demand in recent decades driven by industry, humanity is facing a water crisis. Demand is expected to outstrip supply by 40% in 2030, if current trends continue.

The essence of global water scarcity is the geographic and temporal mismatch between freshwater demand and availability.  The increasing world population, improving living standards, changing consumption patterns, and expansion of irrigated agriculture are the main driving forces for the rising global demand for water. Climate change, such as altered weather-patterns (including droughts or floods), deforestation, increased pollution, green house gases, and wasteful use of water can cause insufficient supply. At the global level and on an annual basis, enough freshwater is available to meet such demand, but spatial and temporal variations of water demand and availability are large, leading to (physical) water scarcity in several parts of the world during specific times of the year. Scarcity varies over time as a result of natural hydrological variability, but varies even more so as a function of prevailing economic policy, planning and management approaches. Scarcity can be expected to intensify with most forms of economic development, but, if correctly identified, many of its causes can be predicted, avoided or mitigated.

Some countries have already proven that decoupling water use from economic growth is possible. For example, in Australia, water consumption declined by 40% between 2001 and 2009 while the economy grew by more than 30%. The International Resource Panel of the UN states that governments have tended to invest heavily in largely inefficient solutions: mega-projects like dams, canals, aqueducts, pipelines and water reservoirs, which are generally neither environmentally sustainable nor economically viable. The most cost-effective way of decoupling water use from economic growth, according to the scientific panel, is for governments to create holistic water management plans that take into account the entire water cycle: from source to distribution, economic use, treatment, recycling, reuse and return to the environment.

Supply and demand

Global use of freshwater, 2016 FAO data

 

Global water consumption 1900–2025, by region, in billions m3 per year

The total amount of easily accessible freshwater on Earth, in the form of surface water (rivers and lakes) or groundwater (in aquifers, for example), is 14.000 cubic kilometres (nearly 3359 cubic miles). Of this total amount, 'just' 5.000 cubic kilometres are being used and reused by humanity. Hence, in theory, there is more than enough freshwater available to meet the demands of the current world population of more than 7 billion people, and even support population growth to 9 billion or more. Due to the unequal geographical distribution and especially the unequal consumption of water, however, it is a scarce resource in some parts of the world and for some parts of the population.

Scarcity as a result of consumption is caused primarily by the extensive use of water in agriculture/livestock breeding and industry. People in developed countries generally use about 10 times more water daily than those in developing countries. A large part of this is indirect use in water-intensive agricultural and industrial production processes of consumer goods, such as fruit, oilseed crops and cotton. Because many of these production chains have been globalized, a lot of water in developing countries is being used and polluted in order to produce goods destined for consumption in developed countries.

Physical and economic scarcity

Water scarcity can result from two mechanisms:

• physical (absolute) water scarcity
• economic water scarcity

Physical water scarcity results from inadequate natural water resources to supply a region's demand, and economic water scarcity results from poor management of the sufficient available water resources. According to the United Nations Development Programme, the latter is found more often to be the cause of countries or regions experiencing water scarcity, as most countries or regions have enough water to meet household, industrial, agricultural, and environmental needs, but lack the means to provide it in an accessible manner. Around one-fifth of the world's population currently live in regions affected by Physical water scarcity, where there are inadequate water resources to meet a country's or regional demand, including the water needed to fulfill the demand of ecosystems to function effectively. Arid regions frequently suffer from physical water scarcity. It also occurs where water seems abundant but where resources are over-committed, such as when there is overdevelopment of hydraulic infrastructure for irrigation. Symptoms of physical water scarcity include environmental degradation and declining groundwater as well as other forms of exploitation or overuse.

Economic water scarcity is caused by a lack of investment in infrastructure or technology to draw water from rivers, aquifers or other water sources, or insufficient human capacity to satisfy the demand for water. One-quarter of the world's population is affected by economic water scarcity. Economic water scarcity includes a lack of infrastructure, causing the people without reliable access to water to have to travel long distances to fetch water, which is often contaminated from rivers for domestic and agricultural uses. Large parts of Africa suffer from economic water scarcity; developing water infrastructure in those areas could, therefore, help to reduce poverty. Critical conditions often arise for economically poor and politically weak communities living in an already dry environment. Consumption increases with GDP per capita: in most developed countries the average amount is around 200–300 liters daily. In underdeveloped countries (e.g. African countries such as Mozambique), average daily water consumption per capita was below 10 L. This is against the backdrop of international organizations, which recommend a minimum of 20 L of water (not including the water needed for washing clothes), available at most 1  km from the household. Increased water consumption is correlated with increasing income, as measured by GDP per capita. In countries suffering from water shortages water is the subject of speculation.

Human right to water

In Meatu district, Simiyu Region, Tanzania (Africa), water most often comes from open holes dug in the sand of dry riverbeds, and it is invariably contaminated. Many children are deprived of an education primarily due to this daily task.

Further information: Right to water

The United Nations Committee on Economic, Social and Cultural Rights established a foundation of five core attributes for water security. They declare that the human right to water entitles everyone to sufficient, safe, acceptable, physically accessible, and affordable water for personal and domestic use.

Sustainable Development Goals

Sustainable Development Goal 6 is about "clean water and sanitation for all." It is one of 17 Sustainable Development Goals established by the United Nations General Assembly in 2015. Its official wording is: "Ensure availability and sustainable management of water and sanitation for all." The goal has eight targets to be achieved by at least 2030. Progress toward the targets will be measured by using eleven indicators. The Sustainable Development Goals replaced the Millennium Development Goals in 2016.

The full title of Target 6.1 is: "By 2030, achieve universal and equitable access to safe and affordable drinking water for all". The full title of Target 6.2 is: "By 2030, 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."

Effects on environment

Water scarcity has many negative impacts on the environment, such as adverse effects on lakes, rivers, ponds, wetlands and other fresh water resources. The resulting water overuse that is related to water scarcity, often located in areas of irrigation agriculture, harms the environment in several ways including increased salinity, nutrient pollution, and the loss of floodplains and wetlands.  Furthermore, water scarcity makes flow management in the rehabilitation of urban streams problematic.

An abandoned ship in the former Aral Sea, near Aral, Kazakhstan

Through the last hundred years, more than half of the Earth's wetlands have been destroyed and have disappeared. These wetlands are important not only because they are the habitats of numerous inhabitants such as mammals, birds, fish, amphibians, and invertebrates, but they support the growing of rice and other food crops as well as provide water filtration and protection from storms and flooding. Freshwater lakes such as the Aral Sea in central Asia have also suffered. Once the fourth largest freshwater lake, it has lost more than 58,000 square km of area and vastly increased in salt concentration over the span of three decades.

Subsidence, or the gradual sinking of landforms, is another result of water scarcity. The U.S. Geological Survey estimates that subsidence has affected more than 17,000 square miles in 45 U.S. states, 80 percent of it due to groundwater usage. In some areas east of Houston, Texas the land has dropped by more than nine feet due to subsidence. Brownwood, a subdivision near Baytown, Texas, was abandoned due to frequent flooding caused by subsidence and has since become part of the Baytown Nature Center.

Climate change

Aquifer draw down or over drafting and the pumping of fossil water increases the total amount of water within the hydrosphere subject to transpiration and evaporation processes, thereby causing accretion in water vapour and cloud cover, the primary absorbers of infrared radiation in the earth's atmosphere. Adding water to the system has a forcing effect on the whole earth system, an accurate estimate of which hydrogeological fact is yet to be quantified.

Depletion of freshwater resources

Lake Chad has shrunk by 90% since the 1960s.

Apart from the conventional surface water sources of freshwater such as rivers and lakes, other resources of freshwater such as groundwater and glaciers have become more developed sources of freshwater, becoming the main source of clean water. Groundwater is water that has pooled below the surface of the Earth and can provide a usable quantity of water through springs or wells. These areas where groundwater is collected are also known as aquifers. Glaciers provide freshwater in the form meltwater, or freshwater melted from snow or ice, that supply streams or springs as temperatures rise. More and more of these sources are being drawn upon as conventional sources' usability decreases due to factors such as pollution or disappearance due to climate changes. Human population growth is a significant contributing factor in the increasing use of these types of water resources.

Groundwater

Until recent history, groundwater was not a highly utilized resource. In the 1960s, more and more groundwater aquifers developed. Changes in knowledge, technology and funding have allowed for focused development into abstracting water from groundwater resources away from surface water resources. These changes allowed for progress in society such as the "agricultural groundwater revolution", expanding the irrigation sector allowing for increased food production and development in rural areas. Groundwater supplies nearly half of all drinking water in the world. The large volumes of water stored underground in most aquifers have a considerable buffer capacity allowing for water to be withdrawn during periods of drought or little rainfall. This is crucial for people that live in regions that cannot depend on precipitation or surface water as a supply alone, instead providing reliable access to water all year round. As of 2010, the world's aggregated groundwater abstraction is estimated at approximately 1,000 km³ per year, with 67% used for irrigation, 22% used for domestic purposes and 11% used for industrial purposes. The top ten major consumers of abstracted water (India, China, United States of America, Pakistan, Iran, Bangladesh, Mexico, Saudi Arabia, Indonesia, and Italy) make up 72% of all abstracted water use worldwide. Groundwater has become crucial for the livelihoods and food security of 1.2 to 1.5 billion rural households in the poorer regions of Africa and Asia.

Pivot irrigation in Saudi Arabia, April 1997. Saudi Arabia is suffering from a major depletion of the water in its underground aquifers.

Although groundwater sources are quite prevalent, one major area of concern is the renewal rate or recharge rate of some groundwater sources. Extracting from groundwater sources that are non-renewable could lead to exhaustion if not properly monitored and managed. Another concern of increased groundwater usage is the diminished water quality of the source over time. Reduction of natural outflows, decreasing stored volumes, declining water levels and water degradation are commonly observed in groundwater systems. Groundwater depletion may result in many negative effects such as increased cost of groundwater pumping, induced salinity and other water quality changes, land subsidence, degraded springs and reduced baseflows. Human pollution is also harmful to this important resource.

To set up a big plant near a water abundant area, bottled water companies need to extract groundwater from a source at a rate more than the replenishment rate leading to the persistent decline in the groundwater levels. The groundwater is taken out, bottled, and then shipped all over the country or world and this water never goes back. When the water table depletes beyond a critical limit, bottling companies just move from that area leaving a grave water scarcity. Groundwater depletion impacts everyone and everything in the area that uses the water: farmers, businesses, animals, ecosystems, tourism and other users e.g. people reliant on a local well for potable water. Millions of gallons of water out of the ground leaves the water table depleted uniformly and not just in that area because the water table is connected across the landmass. Bottling Plants generate water scarcity and impact ecological balance. They lead to water stressed areas which bring in droughts.

Glaciers

Glaciers are noted as a vital water source due to their contribution to stream flow. Rising global temperatures have noticeable effects on the rate at which glaciers melt, causing glaciers in general to shrink worldwide. Although the meltwater from these glaciers is increasing the total water supply for the present, the disappearance of glaciers in the long term will diminish available water resources. Increased meltwater due to rising global temperatures can also have negative effects such as flooding of lakes and dams and globally catastrophic results.

Measurement

In 2012 in Sindh, Pakistan a shortage of clean water led people to queue to collect it where available

Hydrologists today typically assess water scarcity by looking at the population-water equation. This is done by comparing the amount of total available water resources per year to the population of a country or region. A popular approach to measuring water scarcity has been to rank countries according to the amount of annual water resources available per person. For example, according to the Falkenmark Water Stress Indicator, a country or region is said to experience "water stress" when annual water supplies drop below 1,700 cubic metres per person per year. At levels between 1,700 and 1,000 cubic metres per person per year, periodic or limited water shortages can be expected. When water supplies drop below 1,000 cubic metres per person per year, the country faces "water scarcity". The United Nations' FAO states that by 2025, 1.9 billion people will live in countries or regions with absolute water scarcity, and two-thirds of the world population could be under stress conditions. The World Bank adds that climate change could profoundly alter future patterns of both water availability and use, thereby increasing levels of water stress and insecurity, both at the global scale and in sectors that depend on water.

Other ways of measuring water scarcity include examining the physical existence of water in nature, comparing nations with lower or higher volumes of water available for use. This method often fails to capture the accessibility of the water resource to the population that may need it. Others have related water availability to population.

Another measurement, calculated as part of a wider assessment of water management in 2007, aimed to relate water availability to how the resource was actually used. It therefore divided water scarcity into 'physical' and 'economic'. Physical water scarcity is where there is not enough water to meet all demands, including that needed for ecosystems to function effectively. Arid regions frequently suffer from physical water scarcity. It also occurs where water seems abundant but where resources are over-committed, such as when there is overdevelopment of hydraulic infrastructure for irrigation. Symptoms of physical water scarcity include environmental degradation and declining groundwater. Water stress harms living things because every organism needs water to live.

Renewable freshwater resources

Renewable freshwater supply is a metric often used in conjunction when evaluating water scarcity. This metric is informative because it can describe the total available water resource each country contains. By knowing the total available water source, an idea can be gained about whether a country is prone to experiencing physical water scarcity. This metric has its faults in that it is an average; precipitation delivers water unevenly across the planet each year and annual renewable water resources vary from year to year. This metric also does not describe the accessibility of water to individuals, households, industries, or the government. Lastly, as this metric is a description of a whole country, it does not accurately portray whether a country is experiencing water scarcity. Canada and Brazil both have very high levels of available water supply, but still experience various water related problems.

It can be observed that tropical countries in Asia and Africa have low availability of freshwater resources.

Water stress

GEO-2000 estimate for 2025, 25 African countries are expected to suffer from water shortage or water stress.

The United Nations (UN) estimates that, of 1.4 billion cubic kilometers (1 quadrillion acre-feet) of water on Earth, just 200,000 cubic kilometers (162.1 billion acre-feet) represent fresh water available for human consumption.

More than one in every six people in the world is water stressed, meaning that they do not have sufficient access to potable water. Those that are water stressed make up 1.1 billion people in the world and are living in developing countries. According to the Falkenmark Water Stress Indicator, a country or region is said to experience "water stress" when annual water supplies drop below 1,700 cubic metres per person per year. At levels between 1,700 and 1,000 cubic meters per person per year, periodic or limited water shortages can be expected. When a country is below 1,000 cubic meters per person per year, the country then faces water scarcity . In 2006, about 700 million people in 43 countries were living below the 1,700 cubic metres per person threshold. Water stress is ever intensifying in regions such as China, India, and Sub-Saharan Africa, which contains the largest number of water stressed countries of any region with almost one fourth of the population living in a water stressed country. The world's most water stressed region is the Middle East with averages of 1,200 cubic metres of water per person. In China, more than 538 million people are living in a water-stressed region. Much of the water stressed population currently live in river basins where the usage of water resources greatly exceed the renewal of the water source.

Changes in climate

Another popular opinion is that the amount of available freshwater is decreasing because of climate change. Climate change has caused receding glaciers, reduced stream and river flow, and shrinking lakes and ponds. Many aquifers have been over-pumped and are not recharging quickly. Although the total fresh water supply is not used up, much has become polluted, salted, unsuitable or otherwise unavailable for drinking, industry and agriculture. To avoid a global water crisis, farmers will have to strive to increase productivity to meet growing demands for food, while industry and cities find ways to use water more efficiently.

A New York Times article, "Southeast Drought Study Ties Water Shortage to Population, Not Global Warming", summarizes the findings of Columbia University researcher on the subject of the droughts in the American Southeast between 2005 and 2007. The findings published in the Journal of Climate say that the water shortages resulted from population size more than rainfall. Census figures show that Georgia's population rose from 6.48 to 9.54 million between 1990 and 2007. After studying data from weather instruments, computer models, and tree ring measurements, they found that the droughts were not unprecedented and result from normal climate patterns and random weather events. "Similar droughts unfolded over the last thousand years", the researchers wrote, "Regardless of climate change, they added, similar weather patterns can be expected regularly in the future, with similar results." As the temperature increases, rainfall in the Southeast will increase but because of evaporation the area may get even drier. The researchers concluded with a statement saying that any rainfall comes from complicated internal processes in the atmosphere and are very hard to predict because of the large amount of variables.

Water crisis

When there is not enough potable water for a given population, the threat of a water crisis is realized. The United Nations and other world organizations consider a variety of regions to have water crises of global concern. Other organizations, such as the Food and Agriculture Organization, argue that there are no water crises in such places, but steps must still be taken to avoid one.

Effects of water crisis

There are several principal manifestations of the water crisis.

• Food security in the Middle East and North Africa Region
• Inadequate access to safe drinking water for about 885 million people
• Inadequate access to sanitation for 2.5 billion people, which often leads to water pollution
• Groundwater overdrafting (excessive use) leading to diminished agricultural yields
• Overuse and pollution of water resources harming biodiversity
• Regional conflicts over scarce water resources sometimes resulting in warfare.

Waterborne diseases caused by lack of sanitation and hygiene are one of the leading causes of death worldwide. For children under age five, waterborne diseases are a leading cause of death. According to the World Bank, 88 percent of all waterborne diseases are caused by unsafe drinking water, inadequate sanitation and poor hygiene.

Water is the underlying tenuous balance of safe water supply, but controllable factors such as the management and distribution of the water supply itself contribute to further scarcity.

A 2006 United Nations report focuses on issues of governance as the core of the water crisis, saying "There is enough water for everyone" and "Water insufficiency is often due to mismanagement, corruption, lack of appropriate institutions, bureaucratic inertia and a shortage of investment in both human capacity and physical infrastructure". Official data also shows a clear correlation between access to safe water and GDP per capita.

It has also been claimed, primarily by economists, that the water situation has occurred because of a lack of property rights, government regulations and subsidies in the water sector, causing prices to be too low and consumption too high, making a point for water privatization.

Vegetation and wildlife are fundamentally dependent upon adequate freshwater resources. Marshes, bogs and riparian zones are more obviously dependent upon sustainable water supply, but forests and other upland ecosystems are equally at risk of significant productivity changes as water availability is diminished. In the case of wetlands, considerable area has been simply taken from wildlife use to feed and house the expanding human population. But other areas have suffered reduced productivity from gradual diminishing of freshwater inflow, as upstream sources are diverted for human use. In seven states of the U.S. over 80 percent of all historic wetlands were filled by the 1980s, when Congress acted to create a "no net loss" of wetlands.

In Europe extensive loss of wetlands has also occurred with resulting loss of biodiversity. For example, many bogs in Scotland have been developed or diminished through human population expansion. One example is the Portlethen Moss in Aberdeenshire.

Deforestation of the Madagascar Highland Plateau has led to extensive siltation and unstable flows of western rivers.

On Madagascar's highland plateau, a massive transformation occurred that eliminated virtually all the heavily forested vegetation in the period 1970 to 2000. The slash and burn agriculture eliminated about ten percent of the total country's native biomass and converted it to a barren wasteland. These effects were from overpopulation and the necessity to feed poor indigenous peoples, but the adverse effects included widespread gully erosion that in turn produced heavily silted rivers that "run red" decades after the deforestation. This eliminated a large amount of usable fresh water and also destroyed much of the riverine ecosystems of several large west-flowing rivers. Several fish species have been driven to the edge of extinction and some, such as the disturbed Tokios coral reef formations in the Indian Ocean, are effectively lost. In October 2008, Peter Brabeck-Letmathe, chairman and former chief executive of Nestlé, warned that the production of biofuels will further deplete the world's water supply.

Overview of regions suffering crisis impacts

There are many other countries of the world that are severely impacted with regard to human health and inadequate drinking water. The following is a partial list of some of the countries with significant populations (numerical population of affected population listed) whose only consumption is of contaminated water:

• Sudan (12.3 million)
• Venezuela (5.0 million)
• Ethiopia (2.7 million)
• Tunisia (2.1 million)
• Cuba (1.3 million)

Several world maps showing various aspects of the problem can be found in this graph article.

South Asian woman carrying water on her head, 2016

Water scarcity in Yemen (see: Water supply and sanitation in Yemen) is a growing problem that has resulted from population growth, poor water management, climate change, shifts in rainfall, water infrastructure deterioration, poor governance, and other anthropogenic effects. As of 2011, it has been estimated that Yemen is experiencing water scarcity to a degree that affects its political, economic and social dimensions. As of 2015, Yemen is among the most water scarce countries in the world. The majority of Yemen's population experiences water scarcity for at least one month during the year.

Water deficits, which are already spurring heavy grain imports in numerous smaller countries, may soon do the same in larger countries, such as China and India. The water tables are falling in scores of countries (including Northern China, the US, and India) due to widespread overpumping using powerful diesel and electric pumps. Other countries affected include Pakistan, Iran, and Mexico. This will eventually lead to water scarcity and cutbacks in grain harvest. Even with the overpumping of its aquifers, China is developing a grain deficit. When this happens, it will almost certainly drive grain prices upward. Most of the 3 billion people projected to be added worldwide by mid-century will be born in countries already experiencing water shortages. Unless population growth can be slowed quickly, it is feared that there may not be a practical non-violent or humane solution to the emerging world water shortage.

After China and India, there is a second tier of smaller countries with large water deficits — Algeria, Egypt, Iran, Mexico, and Pakistan.

In the Rio Grande Valley, intensive agribusiness has exacerbated water scarcity issues and sparked jurisdictional disputes regarding water rights on both sides of the U.S.-Mexico border. Scholars, including Mexican political scientist Armand Peschard-Sverdrup, have argued that this tension has created the need for a re-developed strategic transnational water management. Some have declared the disputes tantamount to a "war" over diminishing natural resources.

According to a major report compiled in 2019 by more than 200 researchers, the Himalayan glaciers that are the sources of Asia's biggest rivers – Ganges, Indus, Brahmaputra, Yangtze, Mekong, Salween and Yellow – could lose 66 percent of their ice by 2100. Approximately 2.4 billion people live in the drainage basin of the Himalayan rivers. India, China, Pakistan, Bangladesh, Nepal and Myanmar could experience floods followed by droughts in coming decades. In India alone, the Ganges provides water for drinking and farming for more than 500 million people. The west coast of North America, which gets much of its water from glaciers in mountain ranges such as the Rocky Mountains and Sierra Nevada, also would be affected.

Folsom Lake reservoir during the drought in California in 2015.

By far the largest part of Australia is desert or semi-arid lands commonly known as the outback. Water restrictions are in place in many regions and cities of Australia in response to chronic shortages resulting from drought. The Australian of the year 2007, environmentalist Tim Flannery, predicted that unless it made drastic changes, Perth in Western Australia could become the world’s first ghost metropolis, an abandoned city with no more water to sustain its population. In 2010, Perth suffered its second-driest winter on record and the water corporation tightened water restrictions for spring.

Another city facing a water crisis is Cape Town, South Africa. The government and scientists in the area were preparing for "day zero", meaning that the area was almost completely out of water.The government was hopeful that voluntary conservation efforts and environmental factors would increase the water supply in the reservoirs, but these things did not happen which increased the likelihood of the city running out of potable water. Scientists at the University of Cape Town are concerned because without a water source they are not able to conduct valuable medical research or clinical studies. Day Zero was avoided and restrictions were lifted for residents, but conservation efforts are still in place with uncertainty in rainfall amounts.

Role of corporations

The actions of corporations have historically posed a significant threat to clean and affordable water, with Onondaga Lake, the most polluted lake in America, serving as a prime example. During the late 1800s, people began building near the lake for the beautiful scenery and natural water that it provided. As the area began to develop, a sewage treatment plant was built as well as multiple industrial chemical plants. Because of the lack of environmental protection controls, the industries began to dump waste and chemical byproducts into the lake. The practice continued for years until the lake was closed to swimming in 1940 and closed to fishing in 1970. It was not until 2015 when the lake was reopened for swimming, at a combined cost of "$1.1 billion in public and private money."

Wind and solar power such as this installation in a village in northwest Madagascar can make a difference in safe water supply.

Construction of wastewater treatment plants and reduction of groundwater overdrafting appear to be obvious solutions to the worldwide problem; however, a deeper look reveals more fundamental issues in play. Wastewater treatment is highly capital intensive, restricting access to this technology in some regions; furthermore the rapid increase in population of many countries makes this a race that is difficult to win. As if those factors are not daunting enough, one must consider the enormous costs and skill sets involved to maintain wastewater treatment plants even if they are successfully developed.

Reducing groundwater overdrafting is generally politically unpopular, and can have major economic impacts on farmers. Moreover, this strategy necessarily reduces crop output, which has been argued to be impractical given the current population.

At more realistic levels, developing countries can strive to achieve primary wastewater treatment or secure septic systems, and carefully analyse wastewater outfall design to minimize impacts to drinking water and to ecosystems. Developed countries can not only share technology better, including cost-effective wastewater and water treatment systems but also in hydrological transport modeling. At the individual level, people in developed countries can look inward and reduce over consumption, which further strains worldwide water consumption. Both developed and developing countries can increase protection of ecosystems, especially wetlands and riparian zones. There measures will not only conserve biota, but also render more effective the natural water cycle flushing and transport that make water systems more healthy for humans.

A range of local, low-tech solutions are being pursued by a number of companies. These efforts center around the use of solar power to distill water at temperatures slightly beneath that at which water boils. By developing the capability to purify any available water source, local business models could be built around the new technologies, accelerating their uptake. For example, Bedouins from the town of Dahab in Egypt have installed Aqua Danial's Water Stellar, which uses a solar thermal collector measuring two square meters to distill from 40 to 60 liters per day from any local water source. This is five times more efficient than conventional stills and eliminates the need for polluting plastic PET bottles or transportation of water supply.

Managing water crises

Cape Town water crisis warning

It is alleged that the likelihood of conflict rises if the rate of change within a basin exceeds the capacity of institutions to absorb that change. Although water crises can relate closely to regional tensions, history has shown that cases of cooperation far outnumber acute conflicts over water.

However, lack of cooperation may give rise to regional conflicts in many parts of the world, specially in the global south, largely because of the disputes regarding the availability, use and management of water. For example, the dispute between Egypt and Ethiopia over the Grand Ethiopian Renaissance Dam has escalated in 2020. Egypt sees the dam as an existential threat, fearing that the dam will reduce the amount of water it receives from the Nile.

The key, therefore, lies in strong institutions and cooperation. The Indus River Commission and the 1960 Indus Water Treaty have survived two wars between India and Pakistan despite the two countries' mutual hostility, proving a successful mechanism in resolving conflicts by providing a framework for consultation, inspection and exchange of data. The Mekong Committee has functioned since 1957 and outlived the Vietnam War of 1955–1975. In contrast, regional instability results when countries lack institutions to co-operate in regional collaboration, like Egypt's plan for a high dam on the Nile. However, as of 2019 no global institution supervises the management of trans-boundary water sources, and international co-operation has happened through ad hoc collaboration between agencies, like the Mekong Committee which formed due to an alliance between UNICEF and the US Bureau of Reclamation. Formation of strong international institutions seems to provide a way forward – they encourage early intervention and management, avoiding costly dispute-resolution processes.

One common feature of almost all resolved disputes is that the negotiations had a "need-based" instead of a "right–based" paradigm. Irrigable lands, population, and technicalities of projects define "needs". The success of a need-based paradigm is reflected in the only water agreement ever negotiated in the Jordan River Basin, which focuses in needs not on rights of riparians. In the Indian subcontinent, the irrigation requirements of Bangladesh determine water allocations of the Ganges River.^{[citation needed]} A need-based, regional approach focuses on satisfying individuals with their need of water, ensuring that minimum quantitative needs are met. It removes the conflict that arises when countries view the treaty from a national-interest point-of-view and move away from a zero-sum approach to a positive-sum, integrative approach that equitably allocates water and its benefits.

The Blue Peace framework developed by Strategic Foresight Group in partnership with the governments of Switzerland and Sweden offers a unique policy structure which promotes sustainable management of water resources combined with cooperation for peace. By making the most of shared water-resources through cooperation rather than mere allocation between countries, the chances for peace can increase. The Blue Peace approach has proven effective in (for example) the Middle East and the Nile basin. NGOs like Water.org, There Is No Limit Foundation, and Charity: Water are leading the way in providing access to clean water.

Water production

The solutions for the various national water crisis are partly (fresh)water protection and production with different technologies.

Wastewater treatment

The treatment of wastewater helps to protect natural waterbodies and has started to become a source of drinking water in places like Singapore.

Solar humidification and dehumidification

Many atmospheric water generators operate in a manner very similar to that of a dehumidifier: air is passed over a cooled coil, causing water to condense.  Some of its advantages are their low price, the absence of heavy metals and bacteria improving populations health and their versatility of use of air as source of water, without the need of a lake, river or ocean nearby.

Desalination

Desalination machines are designed to extract mineral components from saline water. More generally, desalination refers to the removal of salts and minerals from a target substance.  Energy efficient desalination with an electricity use of less than 1,0 kwh per cubic metre of freshwater can be regarded as the end to the global water crisis. Several companies have developed technologies under this value like Siemens and TS Prototype-Creation. 1,0 kwh is little more than that required for pumping of water in the national grit in Germany. The IBTS Greenhouse, designed for water desalination produces distilled water with 0,45 kwh per cubic metre.

The advent of compact fusion and small nuclear reactors also signifies a solution to the global water crisis as this would mean that the energy expenditure for desalination would not be of importance any more.