AGRICULTURAL WATER UTILIZATION practices over the centuries have gone from taking advantage of the annual
flooding of the Nile River and the use of canals, to the active pumping of
water from aquifers to use for irrigating crops.
An important agricultural-use example is the Ogallala aquifer,
located in eight U.S. states: South Dakota, Wyoming, Colorado, Nebraska,
Kansas, Oklahoma, Texas, and New Mexico. One of the world’s most important
aquifers, it provides one-third of the agricultural irrigation water used in
the entire U.S. It is now being emptied more rapidly than rainfall is
replenishing it, the usage having reduced the average depth of the water by
about 2/3. The aquifer is predicted to run dry by 2040. (Kallen, 2015)
MULTIPLE USES
Water used in raising cattle, for example, is quite large,
as it takes 2500 gallons per pound of beef, and Americans consume about 50
billion pounds of beef each year. A pound of soybean-based tofu, on the other
hand, requires only 228 gallons of water. Some conservationists are even
promoting Meatless Mondays. (Kallen, 2015)
Sometimes energy and conservation goals are in conflict. In
the United States’ Ogallala Aquifer, corn consumes about 90% of the crops’ feed
water. Of the corn produced, 30% is used in food and beverages for humans;
another 30% is used to feed farm animals; 40% of the corn is turned into
ethanol, which the EPA has mandated be applied to most gasoline so that it
contains 10% ethanol. The goal was partly to make the United States more energy
independent, and partly to make the emissions from vehicles have less carbon
dioxide. Raising corn does reduce somewhat the emissions of the vehicles,
offset somewhat by the additional use of gasoline-burning farm equipment.
Farming typically requires nitrogen-based fertilizers, some of which run off into
the regional rivers, such as the Mississippi. Nitrogen compounds in the water
lead to algal blooms, which deprive water of oxygen, bringing that level of
oxygen below that which can sustain marine life. Furthermore, it takes 800
gallons of water to produce just 1 gallon of ethanol. On the other hand, the
use of water for this biofuel production in the aquifer area accounts for only
1% of the freshwater use. (Kallen, 2015)
Only 2.5% of the world’s water is freshwater, with almost
70% frozen in glaciers as ice; 30% is in groundwater, with only 1.2% of that as
surface water. Thus, surface water is 0.01% of the total amount of water on
earth. (Gallagher, 2017) The total amount of water on our planet is 1.5 billion
cubic meters, and fresh water is only 2.5% of this (IAEA, 2011). [International
Atomic Energy Agency, (2011). All About
Water. Retrieved from
https://www.iaea.org/sites/default/files/publications/
magazines/bulletin/bull53-1/53105911720.pdf]
Americans are used to getting their drinking water from the
tap at a cost of 0.1 to 2 cents per gallon. Household use of water averages 100
gallons per day per American, with only one-half gallon of that used for
drinking…the rest goes to washing things and watering lawns. Contrast this with
Africa, where a third of its billion people have too little water for personal
use, a usage estimated by the United Nations as 13 gallons per day. Much of
that water is transported by women carrying jugs, often laboring at this task
for many hours per day. (Kallen, 2015)
WORLDWIDE TRENDS IN WATER USE
By the middle of the 21st century, naturally occurring
drinking water in most regions of the world will turn into a scarce product,
and potable supplies will have to be provided through its importation, as well
as through various, often costly, desalination and purification technologies
(McClelland, 2017).
The essentially infinite supply of water in the oceans can
be made potable by removing the salts from the fluid. Evaporation followed by
condensation of the vapor produces distilled water, virtually 100% pure. While
there is plenty of water in the oceans, desalinization by
evaporation-condensation or by reverse-osmosis (similar to filtering) is
generally prohibitively expensive currently. (Kallen, 2015)
Depending on the source of heat and the method of
condensation, this can provide clean water at a practical price in some
locations. A recent university study (Song et al., 2018) showed the ability to
use carbon-dipped paper to produce 2.2 liters per hour of clean water in sunlight
per square meter of material. They enhanced the efficiency of their method by
absorbing heat from the surroundings, adding this to the heat from the
sunlight. Such a technique might be useful, at first, in disaster situations.
An
even more difficult situation can arise with water for commercial/ technical
needs (primarily irrigation). Shortages already are reality for many agrarian
and some densely populated industrial zones of the world (McClelland, 2017).
Less visible, but increasingly relevant, critical linkages
are “water - food” and “water - energy.” Agriculture accounts for about 70% of
the total amount of freshwater consumed (Revenga, 2002). Therefore, an increase
in food prices, which inevitably follows water depletion, places the
development of strategies for improving resource management, including the
dissemination of existing and development of new watersaving technologies, into
the category of the most urgent (Revenga, 2002).
Competition for water resources between the agricultural
and energy sectors is growing. To produce one liter of biofuels, 2500 liters of
water are needed (UNESCO, 2009). There arises the complex situation requiring
choosing between the development of new technologies and the satisfaction of
the daily elementary needs of millions and even billions of people (UNESCO,
2009).
The availability of fresh water is an essential factor of
national security. Adequate water supplies would likely help in avoiding
conflicts of various kinds. In many regions of the world, water scarcity contributes
to perpetual conflict (UNESCO, 2009). Authoritative sources have raised this
issue emphatically (UNESCO, 2009).
According to Chellaney (2007), in the article, “Preventing
Water Wars in Asia,” analyzing the water crises faced especially by China and
India: “Lack of water in much of Asia begins to threaten rapid economic
modernization, prompting the construction in the headwaters of the rivers, the
waters of which belong to several states. If the geopolitics of water continue
to stimulate tensions between states because of the diminishing water flows in
neighboring states, the Asian renaissance will significantly slow down. Water
becomes the key problem that will determine whether Asia is managing with a
sense of mutually beneficial cooperation or under serious interstate
competition. No country can exert influence greater than China, which controls
the Tibetan Upland - the source of most major rivers in Asia.”
Water problems are characterized by an unconventional
combination of socio-economic, political, legal (international and domestic),
military and civilian aspects (Chellaney, 2007), a particular type of new
cross-border challenges and security threats. At the same time, political and
legal regimes for the functioning of transboundary water resources in crisis
zones are usually not well defined and are de
facto not observed by the parties concerned (Chellaney, 2007).
There are four
crisis zones, where a combination of various water problems generates
severe interstate conflicts predicted to worsen as the global water shortage
problem worsens (Kimenyi and Mbaku, 2016). In all four crisis zones, water
problems combine with the presence of many other threats and security
challenges:
1. A
complex of conflicts regarding the use of the Nile waters between Egypt and the
neighboring countries (Kimenyi and Mbaku, 2016).
2. A
complex of disagreements between the Central Asian countries over the use of
the Syr-Darya waters and, to a lesser extent, the Amu Darya (Kimenyi and Mbaku,
2016).
3. Serious
friction between Israel, Palestine, Syria, and Jordan over the use of the
waters of the Jordan River, constituting an essential element of the
Arab-Israeli conflict (Environment Conflict Cooperation Platform, 2018).
4. Conflicts
among Turkey, Syria, and Iraq over the use of the waters of the Euphrates
River. The implementation of the Turkish “irrigation project of South-Eastern
Anatolia” can reduce river flow to Syria by 50% (Al-Muqdadi et al. 2016).
Population growth
and further industrialization can be expected to put more demands on the
supply of clean water. As the global water shortage worsens, the formation of
new conflict zones is possible. At present, there are no international
organizations that can effectively influence the problems of transboundary
water conflicts (Al-Muqdadi et al. 2016). The reason is the close interlacing
of the above-described economic and security factors. These factors neutralize
all possible efforts of global political and economic, as well as regional,
organizations (Al-Muqdadi et al. 2016).
The possibility of forming a global water market and the
need for its international regulation present problems and opportunities that
further complicate the situation. In this connection, the creation of a new
governance body, preferably within the framework of the UN system, that could
regulate complex global water problems becomes urgent.
A negative impact on the situation may be imposed by
privatization activity in the sphere of water resources (Al-Muqdadi et al.
2016). According to the UN definition, water is considered common property, and
free access to water use belongs to the category of basic human needs, the area
of its natural rights (Purvis, 2017). As discussed below, when a resource is
shared without clear-cut ownership, the “tragedy of the commons” effect can
lead to over-use and under-investment.
In the twentieth century, the water services sector was
wholly provided with state structures for a long time. In most countries, there
is a state communal economy. However, the public sector often has low
efficiency, and its services are of poor quality and insufficient coverage. In
the second half of the 1980s, many countries began to attract private capital
to water management (Purvis, 2017). There was an opportunity to connect private
financial resources to expand the coverage of the population with services and
at the same time to ease budget expenditures (Purvis, 2017).
Today, the amount of services provided by the private
sector in the sphere of water consumption is estimated at $200 billion a year
and, according to the World Bank projections, by 2021 this figure will reach $1
trillion annually (World Bank, 2018). The private sector, in contemporary
discussions, often appears as a panacea that can solve the problem of lack of
fresh water. However, for the time being, the fact is that it provides only 7%
of the world population with water (World Bank, 2018).
Serious problems associated with privatization processes in
the water sector are the rising prices for consumed water and the growing dependence
of the population of developing countries on foreign sources of drinking water
supply (World Bank, 2018). It is possible that privatization will produce
investments and innovation that will lead to lowered water costs, but this is
speculative.
Privatization of the water supply system and the resulting
increase in water prices have repeatedly led to mass protests of the population
in Latin America and South Africa (World Bank, 2018). Therefore, the prospects
for privatization of water supply are unclear. However, the rivalry between the
public and private sectors, as well as competition between business
representatives, cannot be ignored in assessing the conflict potential of the
world’s water resources (World Bank, 2018).
WATER SHORTAGE AS A SIGNIFICANT GLOBAL RISK
Even when surrounded by source(s) of water, we can feel
thirsty. Almost three-quarters of the Earth’s surface is covered with water,
but fresh water on the planet is less than 3% of this, and only 1% of it is
easily accessible (W E Forum, 2016). We are all vitally dependent on this tiny
percentage.
In the list of the most significant global risks for
humanity compiled by the World Economic Forum for the next ten years, based on
the criterion of potential impact, the problem of shortage of drinking water
came out on top (W E Forum, 2016). Failed attempts to mitigate climate change
have left behind the possibility of increasingly extreme weather conditions, as
well as threats to food security. These risks are interrelated.
Four billion people, for at least one month of the year,
face a deficit of fresh water. According to a study published by Mekonnen and
Hoekstra (2016), almost half of these people live in India and China. The same
study concluded that 663 million people have a lack of drinking water, and
another 2.4 billion do not have standard sanitation conditions (Mekonnen and
Hoekstra, 2016).
There is no reason to look to the clean water future with
optimism; on the contrary, increasingly we are likely to see global problems in
the coming decades associated with water (W E Forum, 2016). Experts predict
that two-thirds of humanity will face a shortage of fresh water, while
ironically the number of people affected by floods will triple by the end of
the century (W E Forum, 2016).
WHAT FUELS THE SHORTAGE OF WATER RESOURCES?
Natural, uneven distribution of
water resources between regions of the planet
The most significant adverse effect of the lack of water
resources is experienced by the countries of tropical Africa, where the cost of
water determines the development of the economy of entire regions (McClelland,
2017). The consequences of predicted climate changes will exacerbate the
situation regarding water scarcity: these two factors negatively affect
agriculture, healthcare, and income of the population. According to the
forecasts of the World Bank, the GDP of several African countries may drop by 6%
by 2050 (McClelland, 2017). The situation is aggravated by the low level of
development of some nation states located to the south of the Sahara. To
achieve a satisfactory level of water supply and sanitation, the economies of
these countries will need investments of about 2.7% of GDP, or $7 billion a
year (McClelland, 2017).
The rapid growth of urbanization
increases the need for water
In addition to factors related to climate change, two other
megatrends are involved in the predicted shortage of water resources:
population growth and urbanization. More than half the world’s population
currently lives in cities, and by 2050, the percentage of the world population
that is urban will reach 66% (UNESCO, 2009). This means that another 2 billion
inhabitants will need fresh water for drinking, washing, and cooking.
According to the UN forecasts, about 90% of urban
population growth will be concentrated in Asia and Africa, where the problem of
water deficit is most pronounced (UNESCO, 2009). However, other regions,
regardless of the climatic zone and geographic zone, are not immune from
imminent problems with drinking water. For example, Brazil, the birthplace of
tropical forests and the storage of an eighth of the world’s freshwater
supplies, as a result of rapid urbanization has faced droughts that are more
typical of desert Iran (UNESCO, 2009).
Agriculture uses 70% of the
world’s freshwater resources
About 60% of this water volume is lost due to leaky
irrigation systems, inefficient technologies, drainage of marshy areas, and the
growing of crops that consume too much water (rice, for example) (UNESCO,
2009). Such a cavalier approach to water usage leads to the drying up of
rivers, lakes, and even underground waters (aquifers). Many countries producing
a multitude of food products, including India, China, Australia, Spain, and the
United States, have already reached, or are close to reaching, their water
reserves limits (UNESCO, 2009)
Water Pollution
Many factors lead to water pollution: pesticides and
fertilizers washed away from farmland, untreated sewage, and industrial waste.
Moreover, in the case of toxic wastes that industrial enterprises have
discarded, all the negative consequences on the environment and the food chain
may not immediately appear (UNESCO, 2009).
In general, pollution control is likely to raise the cost
of goods and services, thus becoming an economic and political issue.
Because of widespread public concern about water pollution,
the U.S. Clean Water Act of 1972 was passed, requiring the U.S. EPA to identify
and regulate point sources of water pollution and requiring factories and water
treatment plants to improve their pollution-control activities (Kallen, 2015).
In 1974, the U.S. Safe Drinking Water Act was passed to
improve the safety of United States tap water. Public water systems were
required to test for and achieve drastically reduced levels of contaminants in
drinking water (Kallen, 2015). In some cases, these regulations have forced
businesses to close their doors.
Wide-area pollutant sources still contribute substantially
to water pollution, an example being agricultural facilities. Important among
these are “concentrated animal feeding operations.” In one case, such an
operation produced 1½ times the water pollutants produced by the people in the
Pennsylvania city of Philadelphia (Kallen, 2015).
The recently developed fracking oil-recovery technique that
allows for increasing the recovery of oil from wells has placed more demands on
water supplies in areas using this technology. The degree to which the fracking
fluids can penetrate the generally impervious rock layers between the oil
fields and the aquifers is a matter of dispute. Often fracking occurs not far
from human habitations. Many other countries have adopted fracking technology,
too.
Of course, the U.S. is not the only major country with
water pollution problems. As with air pollution, water pollution is a major
problem in China. In 2013, the Chinese minister of environmental policy said
that at least one-quarter of his country’s rivers were too contaminated to use
for drinking or crops and even for industrial applications (Kallen, 2015).
Agriculture is so important to China that it must continue its water usage
despite concerns for the purity of the water in use. Chinese activists recently
produced an Internet campaign to call attention to the need for improved
pollution control.
IMPROPER HANDLING OF WATER RESOURCES CAN HAVE
CATASTROPHIC CONSEQUENCES
The most obvious catastrophic example is the Aral Sea,
located in Central Asia. Once, it was the fourth-largest freshwater lake in the
world. But in just three decades, as a result of ill-considered actions to
flood the region, the surface area of
the Aral Sea has decreased by 90% (Qobil, 2015). And because of
pollution and leakage of water intended for irrigation and power generation,
the salinity of that water has increased by seven times. Drying out, the Aral
Sea has left the land contaminated (Qobil, 2015). This human-made environmental
disaster led to a shortage of food, an increase in infant mortality, and a
decrease in the life expectancy of the local population (Qobil, 2015). The
local climate even seems to have changed: in summer it is hotter and drier, and
in winter it is colder.
The growth of the Earth’s population, increased water
consumption, and destruction of natural ecosystems have meant that by the
beginning of the 21st century, drinking and technical water had become one of
the most important types of resources needed not only for global economic
growth but even for the mere survival of humankind (UNESCO, 2009).
Water resources are the second most important natural
resource for national development, after oil and gas. No less than for
drinking, clean water is essential for agriculture, hydro-power, biofuel
production, as well as in various water-intensive industries and in public
services (UNESCO, 2009).
Annually, about 6 million hectares of land turn into
desert. Every day, world-wide, about 6000 people die due to unsatisfactory
hygienic conditions caused by water shortages (UNESCO, 2009). On more than 20%
of the Earth’s land area, anthropogenic activity has exceeded the limits of the
capacity of natural ecosystems that serve to meet human needs but now have been
fundamentally changed.
Water quality continues to deteriorate. Each year, 160
billion cubic meters are taken from the groundwater, and up to 95% of the
liquid industrial waste is discharged into the reservoirs uncontrolled (UNESCO,
2009).
Many countries are over-pumping their aquifers, withdrawing
more water than is being replaced by rainfall; rainfall becomes divided into
surface water, groundwater, and evaporation.
India faces severe water shortages, with 16% of the world’s
population but only 4% of its freshwater. It has no restrictions on the
agricultural use of water; it has produced record harvests, but this cannot
continue (Kallen, 2015). Even so, one newspaper in India estimated that half
the childhood deaths were due to malnutrition. You might think that the yearly
monsoons would provide India with enough water, and they could, but better
water capture and conservation methods must be adopted. One expert estimated
that 80% of the difference between the supply of water and the demand could be
handled by increased efficiency of water capture and use in India.
WATER WASTE
About seven billion gallons a day of clean water go down
the drain just from leaking faucets (Kallen, 2015).The U.S. has about a million
miles of water pipes, and the American Society of Civil Engineers estimates a
quarter-million of these water mains break each year. To replace the entire
system would cost roughly $1 trillion, the ASCE estimates (Kallen, 2015).
Rooftop gardens and water-catchment systems can help reduce
the waste of rainwater, but these require investment and maintenance.
The purpose of our work is to analyze the problem of a
possible shortage of clean water in part of the United States, the Colorado
River Basin, as well as the development of recommendations to solve this
problem.
CAUSES OF THE WATER CRISIS
The lack of water resources is often the result of human
activity. The reasons for this situation are numerous. We will consider the
most significant.
The primary sources of fresh water are rivers, lakes,
aquifers, and marshes. Unfortunately, the natural distribution of resources is
uneven across the globe (IAEA, 2011). For example, Europe has 20% of the
inhabitants of the entire planet, but only 7% of its water reserves (IAEA,
2011). The number of people on Earth is growing every day, and with them grows
the need for drinking water (IAEA, 2011). For example, if the annual increase
in people is 84 million people, then the necessary increase in water resources
should be at least 60 million cubic meters per year (IAEA, 2011).
Misuse of natural resources leads to their rapid decrease.
Furthermore, groundwater recovers very slowly – about 1% per year (IAEA, 2011).
Also important is the pollution of water sources due to industrial effluents
and the flushing of fertilizers from fields (IAEA, 2011). For example, in
America (e.g., the Colorado/Utah mine spill), 37% of rivers and lakes are so
polluted that it is not even possible to swim in them safely (IAEA, 2011).
Colorado has more than 20,000 abandoned sub-surface mines, most of them now
filled with water, which, when it leaches out, contaminates other water it
contacts. (Owen, 2017)
Even the positive factor of development of agriculture
around the world also contributes to water pollution. Agricultural uses make up
85% of the total (IAEA, 2011). The price of agricultural products is made more
expensive when it is necessary to irrigate to produce them (IAEA, 2011). In the
U.S., drought conditions between 2010 and 2013 influenced many farmers to
change from growing wheat and corn to sorghum, requiring less water, and to
change their irrigation systems to “trickle” systems from wasteful spray
systems.
GLOBAL WARMING
One of the future global challenges is the warming of the
Earth’s atmosphere due to the greenhouse effect, as more gases like carbon
dioxide are emitted into the atmosphere. The Earth’s climate may be changing
yearly, perhaps evidenced by unusual weather such as snowfall in countries with
hot climates and unnatural frosts in countries such as Italy and Spain (IAEA,
2011), consequences of the redistribution of precipitation.
Predictions of climate change raise more issues. The United
Nations panel on climate change concluded that the United States has seen an
average temperature increase of 2° F since 1960, something hard to notice but
capable of producing climate problems. Some climate scientists believe that
such an increase can create drought in the U.S. and in Africa. However, it is
also true that some of the most powerful rainfalls have occurred in the recent
past.
A recent article in the Wall
Street Journal by Michaels and Maue (June 21, 2018)
[https://www.wsj.com/articles/thirty-years-on-how-welldo-global-warming-predictions-stand-up-1529623442]
compared current temperatures with those predicted by former NASA scientist
James E. Hansen in U.S. congressional testimony 30 years ago. The atmosphere
has heated barely at all, less than his predictions, and about half those
predicted by the U.N. Intergovernmental Panel on Climate Change (UNIPCC).
Modeling that better accounts for the counteracting action of atmospheric
aerosol particles also predicts the diminished heating effect. Doubling the
level of carbon dioxide in the atmosphere is predicted to raise the average
temperature 2 to 4 oC.
80% of the world’s fresh water is tied up in the ice in
Antarctica. If there is appreciable warming, some of this ice will melt. This
freshwater melt is not in a convenient location for use by humans. However, it
may cause the seas to rise dangerously. A warmer climate should have more
rainfall and evaporation, changing the water situation in various areas, likely
causing more floods and droughts. Earlier melting of ice cover on lakes and the
oceans will lead to more evaporation; higher temperatures give higher
evaporation rates, and eventually this water must precipitate as rain or snow.
(Kallen, 2015) Increases in moisture in the atmosphere will increase cloud
cover, which tends to produce warmer nights and cooler days.
A Bloomberg News
article by Christopher Flavelle posted on January 22, 2019
[https://www.bloomberg.com/news/articles/2019-01-22/
muggy-disney-parks-downed-at-t-towers-firms-tally-climate-
risk?srnd=premium] confirms the adage that it is an ill
wind that blows nobody any good. Flavelle’s article has the headline “Climate
Changed:
Corporate America Is Getting Ready to Monetize Climate
Change.”
Despite its headline, the article primarily lists risks
that the companies have shown concerns them, publishing through required SEC
statements or in responding to queries from the Carbon Disclosure Project
(CDP):
•
Bank of America: more mortgage defaults due to
flooding,
•
Walt Disney Company: weather uncomfortable in
theme parks,
•
AT&T: fires and floods damage
infrastructure,
•
Coca-Cola: loss of water supplies near bottlers,
•
Intel and other semiconductor manufacturers:
less water, • Visa: more pandemics and
water conflicts, discouraging travel.
“The disclosures were collected
by CDP, a U.K.-based nonprofit that asks companies to report their
environmental impact, including the risks and opportunities they believe
climate change presents for their businesses. More than 7,000 companies
worldwide filed reports for 2018, including more than 1,800 from the U.S.” The
CDP website describes the organization: “CDP is a not-for-profit charity that
runs the global disclosure system for investors, companies, cities, states and
regions to manage their environmental impacts. Over the past 15 years we have
created a system that has resulted in unparalleled engagement on environmental
issues worldwide.”
Returning to the Flavelle (2019) article, we note that some
may gain. What benefits? From near the end of the piece:
“Climate change isn’t all
downside for the largest U.S. companies. Many of those that filed reports with
CDP said they believe climate change can bolster demand for their products.
“For one thing, more people
will get sick. ‘As the climate changes, there will be expanded markets for
products for tropical and weather-related diseases including waterborne
illness,’ wrote Merck & Co. The company didn’t respond to a request for
comment.
“More disasters will make iPhones
even more vital to people’s lives, Apple predicted.”
Despite the Flavelle article’s headline, its content
indicates more commercial worry than confidence.
Three months earlier, again in Bloomberg News [https://www.bloomberg.com/businessweek, October 8,
2018], the same author wrote about climate change and investment opportunities:
“Climate Change Will Get Worse. These Investors Are Betting on It: If electric
cars and clean energy aren’t enough to prevent rising oceans, then there’s
money to be made in sea walls, indoor agriculture, and emergency housing. Sea
levels are predicted to rise, putting at risk some of the 40% of Americans who
live by its coasts.”
Favelle (2018) writes, “Consider what might happen to food
production. As precipitation patterns change and oceans become more acidic,
outdoor environments will become less reliable and ‘more and more intolerant
for crops or fish,’ according to Liqian Ma, managing director at Cambridge
Associates in Boston. Demand will increase for technologies that allow indoor
agriculture and even aquaculture.” One entrepreneur took advantage of a
hurricane’s predicted path to invest in housing in nearby, but safe, areas.
Insurance companies are developing policies that allow investors to take both
sides of the risk expectations. Municipal bond valuations should reflect
climate risk, and some do already.
An important part of the water cycle is the formation of
snow packs and glaciers in the mountainous regions of the Earth. These snow and
ice formations serve as natural reservoirs for fresh water. In the summer,
these melt and feed the streams that flow eventually to the oceans, some of
which rivers and streams are interrupted by artificial and natural holding
areas, reservoirs. For example, snowpack in the Rocky Mountains is the source
of water for some 70,000,000 people in the American Southwest and provides water
for farms in California (Kallen, 2015).
As the world warms, fresh water will become even more
precious. This will be particularly notable in the American Southwest. Asia
will experience significant changes, too. The Tibetan plateau in the Himalayan
Mountains has over 1000 glaciers, which serve as fresh water sources for much
of the Asian continent, helping to fill the major rivers. Over a billion people
are dependent upon these rivers, and the inhabitants constitute roughly 1/6 of
the world’s population. There is concern that these glaciers are melting at an
accelerating rate, leading to questions of future advocacy of water supplies
for these people. China has 20% of the earth’s population and only about 7% of
its fresh water (Kallen, 2015).
Climate change can produce local droughts, and it is
estimated that in Africa there are two million human deaths per year due to
starvation, partly caused by droughts. In the Middle East, by the Tigris and
Euphrates Rivers, it is estimated that between 2006 and 2010, the nation of
Syria lost 1.5 million people from farming due to drought conditions (Kallen,
2015).
Our monograph will focus below on the Colorado River Basin
of the United States, a hydrological area of great significance, one expected
to experience major changes in the coming decades.
