The Great Drought

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Chris Weigmann


Environmental Issues


EG-481


Tanya Gregg


03/31/2010


                                         The Great Drought


The planet is gradually getting hotter and dryer today than it has ever been before in history.

Scientists from the Intergovernmental Panel on Climate carrying out global warming research

have recently predicted that average global temperatures could increase between 1.4 and 5.8

degrees Celsius by the year 2100 (live science). The scientific consensus on climatic changes

related to global warming is that the average temperature of the earth has risen 0.4 and 0.8

degrees over the past 100 years (live science). The increased volumes of carbon dioxide and

other greenhouse gases released by the burning of fossil fuels, land clearing, agriculture, and

other human activities, are believed to be the primary sources of the global warming that has

occurred over the past 50 years (live science).


Global warming is the term used to describe a gradual increase in the average temperature of the

earth’s atmosphere and its oceans (live science). Changes resulting from global warming may

include rising sea levels due to the melting of the polar ice caps, as well as an increase in

occurrence and severity of storms and a major drought in several parts of the world. Of all the
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major effects of climate change that can occur drought is by far the most severe and most

damaging of all of these live science).


Although many scientists and people downplay or exaggerate the effects of a major drought, it is

fast becoming a reality for farmers around the world and can have a major impact on the

landscape, water supply and food supply that’s needed and used in peoples everyday lives. A

major drought can cause food shortages, increased food prices, loss of wildlife habitat,

environmental and social problems. To truly understand the effects drought has on the

environment and the world as a whole, one must understand what drought really is and the

climate forces that can cause it to occur (Bean).


There are many definitions of drought in terms of its outcome on society and the environment

but the generic definition of drought states that it is a persistent and abnormal moisture

deficiency having adverse impacts on vegetation, animals, or people. Declarations of droughts

are often triggered by specific and well defined conditions, such as a specific reservoir level on a

specific date. These drought triggers become the practical definition of drought for a particular

region and for specific issues (Motha). Drought refers to a shortage of water that occurs when

the available supply can’t meet the demand. There are also many contributors to drought like

weather and an increased demand for water or a change in water quality due to issues like

contamination (Bean).


There are four main types of drought:


      Meteorological drought is based on a specified time period with precipitation averaging

       below a critical threshold. This is determined by calculating the lack of precipitation from
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       normal amounts, as well as the length of the dry spell. Meteorological drought is the most

       common of all four types of drought.


      Agricultural drought refers to the lack of sufficient moisture available for crops, forests,

       rangelands, and livestock. Reduced ground water or reservoir levels can be responsible

       for causing this drought. Agricultural drought also looks at the different stages of crops

       and how a lack of water will affect them in a given stage.


      Hydrological drought is associated with water supply systems such as river drainage

       basins and aquifers. It usually occurs later than other types of drought since it takes

       longer for a lack of moisture to become evident in these water sources. Factors such as

       landscape or land use changes can also contribute to this type of drought.


      Societal drought is a complex interaction of the natural phenomenon, environmental

       degradation, and human impact. Its occurrence depends on the time and space processes

       of supply and demand to identify or classify droughts (Motha).


Drought can have a major impact on society and can occur anywhere in the world at any time.

Major droughts that have occurred in the last century are the Dust Bowl of the 1930’s in the

U.S., and the recurring droughts in West Africa between 1968 and 1973. Although these two

major drought episodes had disastrous consequences, drought conditions of varying severity and

magnitude occur around the world in almost any given year. Few areas are spared the natural

occurrence of drought and many areas have suffered from its impact. In the United States,

drought has occurred in various parts of the country on a routine basis. After the 1930’s major

drought episodes occurred in the Southern plains during the early 1950’s, in the Northeast in the
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early 1960’s in the far West during the mid 1970’s and again in the early 1980’s in the Midwest

and parts of the Southeast in 1988, and in Hawaii and the East in the late 1990’s (Motha).

Analysis’s at the National Drought Mitigation Center in Lincoln, Neb, figure that the dry spell

conditions in the U.S. spreads across 14 states along the East Coast and 14 more in a broad swath

that runs down the Rockies and spills into the Plains and the desert Southwest (Petit).


Causes of drought can vary from place to place. In West Africa’s case, excessive overgrazing

denuded a dwindling vegetation resource. In an effort to overcome the loss of water supplies, the

construction of deep wells to tap water inadvertently aggravated the situation by maintaining an

excessive carrying capacity of the land. The extremely delicate balance of nature can be

irreversibly upset by the combination of natural climate variability and mismanagement of the

land. Other causes of drought are:


      Global Warming (Petit)


      Sea changes- unusually warm and cold tracts of ocean water may have set the stage for

       the drought that has settled over parts of the U.S. (Petit).


      Population growth- water scarcity due to the growing demand resulting from population

       increase.


      Food production- insufficient water available to ensure self sufficiency in food

       production. Demand for food increases with increases in population.


      Climatic change and variability- the effect will be to accentuate the extremes with more

       pronounced droughts and more severe flooding.
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      Land use- reduction of vegetation cover reduces ground water infiltration and the storage

       capacity of dams and lakes through siltation. The draining of large scale wetlands or large

       scale deforestation may change the micro climate of a region.


      Water quality- pollution of water supplies reduces the availability of water for use.

       Destruction of the river environment reduces the natural ability of the river to cope with

       pollution.


      Water demand- a growing and unmanaged demand for water will hasten the arrival of

       conditions of scarcity.


      Poverty and economic policy- poverty is a major factor in water scarcity and

       susceptibility to drought.


      Legislation and water resource management- poor or inadequate legislation can

       exacerbate the effects of water scarcity. If policies are inequitable, inefficient, or do not

       provide for at least the basic needs of all citizens, then a particular occurrence of water

       scarcity will result in conditions of drought (Abrahms).


Impacts of drought affect everyone and everything. Humans that are impacted are farmers,

ranchers, commercial fishermen, local businesses, small towns and villages, agricultural workers,

fire fighters, and everyone living in rural areas or along river basins. Drought also affects the

environment and other living or non living things like landscape, wildlife, aquatic species,

forests, crops, plants, organisms, water systems, rivers, lakes, livestock, and many other

economic, environmental and social resources like food, insects, jobs, recreational and tourism,

and energy sources. Drought can cause disease, insect infestation, food and water shortages,
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unemployment, fires, high food prices, inflation, damage to fisheries, increased desertification,

increased predation, increased stress to endangered species, wind and water erosion to soils, loss

of human life due to starvation, dehydration, suicides and violence, mental and physical stress

and political conflicts (Bean).


Drought can have major consequences to the environment and the economy if nothing is done.

At its most severe, drought could create vast, windblown dust bowls, eroding landscape,

damaging terrestrial and aquatic wildlife habitat, contributing to widespread wildfire, and

causing significant monetary losses. Drought may cause economic ruin to farmers and ranchers.

It brings hardship to water dependent enterprises such as commercial fishing. Drought can have a

devastating impact on agricultural workers and lead to difficult decisions regarding allocation of

water and stringent water use limitations. Drought puts drinking water supplies at risk and may

hamper rural fire fighting efforts. Drought creates or exacerbates conflicts over access to river

basins and water systems. Droughts impact is far reaching and damage to the ecosystem may be

irreversible (Motha).


There are several agencies, commissions and groups involved in monitoring, implementing and

developing laws and policies on drought and researching different ways to mitigate it. The

National Drought Policy Commission was created to advise Congress on how to develop a

comprehensive national policy to mitigate the impacts of drought, to improve public awareness,

and to achieve federal/non federal partnerships for better coordination and response to drought. It

also advises Congress on the formulation of a national drought policy based on preparedness,

mitigation, and risk management, and to integrate federal programs with state, local, and tribal

programs to ensure a coordinated approach to drought response. Other private entrepreneurs and
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non- profit groups with an interest in water management and environmental issues work with

governments to carry out drought education projects and water conservation initiatives. State,

local, and tribal governments must deal individually with each federal agency involved with

drought assistance. Although the federal government plays a major role in responding to drought

events, there is no single federal agency in a lead or coordinating position regarding drought. The

National Weather Service manages a cooperative observer network, the U.S. Department of

Agriculture operates an automated weather observing network and a much less dense network

the Soil Climate Analysis Network, in agricultural areas, the U.S. Forest Service operates its own

Remote Automated Weather stations network in the federally managed forest lands, and the U.S.

Geological Survey manages a stream gauging and ground water network for flood monitoring.

There are 39 networks with 33 in operation for less than 20 years, and 15 in existence for less

than 10 years. All these networks have some type of partnership with private industry or

universities. Many have some type of relationship with the public sector as well. Of the 39

networks, 12 indicated some type of arrangement at the federal or national level, and 15 have

some form of partnership with state, provincial, or municipal levels of government (Motha).


Voters, the private sector, and lobbying groups representing various interests influence

government representatives. Scientists also inform government decisions on drought research.

Governmental representatives and agencies formulate policy that aims to address social

problems, including environmental impacts from drought. The Intergovernmental Panel on

Climate Change issues reports on climate change, future trends in temperature, precipitation

patterns, sea levels, storm intensity, and other factors relating to drought. The United Nations,

the World Bank, the European Union and the World Trade Organizations also support and
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provide research and policies regarding drought and its impacts on society and the environment

in order to minimize its effects (Withgott).


There are many environmental policies out there to address drought in the world both

internationally and here in the U.S. Some of the International policies are the National Water

Policy in South Africa and the Water Services Bill which addresses the issue of water usage and

water supply by the people and government of South Africa. It provides for contingency action

to be taken in the event of emergencies and for the Minister or his/her representative to take over

the running of local functions. The document also emphasizes the need to protect and care for the

country’s water resources and the need for demand management to be exercised. The current

policy is mostly directed at increasing the supply of water to the people of South Africa

(Abrahms).


Another International Policy is the International Food Policy in Sudan, which is particularly

concerned with quantitatively tracing the drought production-consumption-nutrition linkages

under famine conditions at the household level in order to identify effective means of alleviating

and preventing famine during a drought (Tesfaye).


The U.S. passed a policy addressing drought and its effects on parts of the country in 1998 called

the National Drought Policy Act. This Act is based on preparedness and mitigation to reduce the

need for emergency relief. It also created the National Drought Policy Commission to advise

Congress on how to develop such a comprehensive national policy to mitigate the impacts of

drought, to improve public awareness, and to achieve federal, non federal partnerships for better

coordination and response to drought. It also directs the Commission to conduct a thorough study

of ongoing drought programs, to present a strategy that shifts form ad hoc federal action toward a
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systematic process similar to those for other natural disasters, and to integrate federal programs

with state, local, and tribal programs to ensure a coordinated approach to drought response

(Motha).


There were several tried solutions to solving the drought problem in the world but many of them

turned out to be unsuccessful. One of the solutions that were tried was in South Africa. The

farmers there tried reducing the vegetation cover on their land in order to produce greater run off.

But instead it reduced groundwater infiltration and the storage capacity of dams and lakes

through siltation. This draining of large scale deforestation caused a change in the mico-climate

of the region (Abrahms). Another tried solution was in West Africa during the recurring droughts

between 1968 and 1973. Excessive overgrazing denuded a dwindling vegetation resource during

those drought years. In an effort to overcome the loss of water supplies, the construction of deep

wells to tap water inadvertently aggravated the situation by maintaining an excessive carrying

capacity of the land (Abrahms). Still another tried and failed solution to drought planning came

in 1965 during the height of a serious drought in the northeastern United States. New York City

stopped releases from its Delaware River reservoirs to maintain its withdrawal rate. With less

fresh water flowing past the city of Philadelphia, there was a risk that salt water would be drawn

into Philadelphia’s water supply system. This led to President Lyndon Johnson convening a

special meeting of governors and mayors from the Delaware Basin that led to emergency

measures for managing the Delaware River (Motha).


There are no real solutions to preventing a major drought from occurring anywhere in the world,

but there are several ways of minimizing and lessoning the impact that they could have on

society and the environment. One major recommendation focuses on improved collaboration
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among scientists and managers to enhance the effectiveness of observation networks,

monitoring, prediction, information delivery, and applied research and to foster public

understanding of and preparedness for drought. Preparedness is the foundation for such a

solution. Another solution is to incorporate planning, implementation of plans and proactive

mitigation measures, risk management, resource stewardship, environmental considerations, and

public education as the key elements of effective national drought policy. Develop and

incorporate comprehensive insurance and financial strategies into drought preparedness plans,

maintain a safety net of emergency relief that emphasizes sound stewardship of natural resources

and self help, and coordinate drought programs and respond effectively, efficiently, and in a

customer oriented manner are a few more recommendations for establishing a drought

management plan and to minimize the effects of drought on the environment and society

(Motha).


To establish an effective national drought information delivery system, a coordinated effort must

be undertaken to bring more systematic data networks to rural and tribal areas. These networks

must be integrated into a national program through partnerships between federal and non federal

entities. A comprehensive information gateway must be established to provide users with free

and open access to observational network data and drought monitoring, prediction, impact,

assessment, preparedness, and mitigation measures. Links among federal and non federal sources

are critical to ensure a comprehensive and collaborative system of data information. These

drought products can then be used by planners and decision makers in a vast array of measures to

cope with this natural disaster. (Motha).


Possible solutions or strategies for drought mitigation include:
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      Desalination of sea water for irrigation or consumption


      Drought monitoring-careful monitoring of moisture levels can also help predict increased

       risk for wildfires.


      Land use-carefully planned crop rotation can help minimize erosion and allow farmers to

       plant less water dependent crops in drier years.


      Rainfall harvesting-collection and storage of rainwater from roofs or other suitable

       catchments.


      Recycled water-former wastewater that has been treated and purified for reuse.


      Transvasement-building canals or redirecting rivers as massive attempts at irrigation in

       drought prone areas.


      Water restrictions-water use may be regulated. This may involve regulating the use of

       sprinklers, hoses or buckets on outdoor plants, the washing of motor vehicles or other

       outdoor hard surfaces, topping up of swimming pools, and also the fitting of water

       conservation devices inside the home (new world).


A possible new solution or solutions could be cloud seeding or a geoengineering scheme that

would inject sulfate particles into Earth’s upper atmosphere to fight global warming. In this

scheme, scientists would scatter light reflecting sulfate particles in the atmosphere as a way to

mitigate climate change. Paul J. Crutzen, winner of the 1995 Nobel Prize in Chemistry for his

work on the hole in the ozone layer, has said that injecting sulfur into the atmosphere could slow

global warming by reflecting solar radiation back into space. This would result in aerosol
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surfaces that would greatly enhance future polar ozone depletion. Although there currently are no

laws regulating this proposed solution, researchers writhing in the journal Science, say this plan

could damage the ozone layer over the Arctic and Antarctic. They say that the ozone layer is

important because it blocks dangerous ultraviolet radiation from the sun. A study by Simone

Tilmes of the National Center for Atmospheric Research warns that regular infections of sulfates

over the next few decades would destroy between one and three quarters of the ozone layer

above the Arctic. Meanwhile, in the Antarctic, this geoengineering scheme could delay the

expected recovery of the current ozone hole by 30 to 70 years (mongabay).


Research indicates that trying to artificially cool off the planet could have perilous effects. More

research is therefore required to determine the full implications of geoengineering before

considering the injection of sulfate aerosols into the stratosphere says co-author Rolf Moeller of

the Jolich Research Center in Germany. The authors said that the loss of ozone could be more

severe if a major volcanic eruption occurred during the geoengineering scheme. Similarly, Ken

Caldeira of the Carnegie Institutions Department of Global Ecology has shown that even if a sun

block solution to solar radiation proved successful, it would not address acidification of the

world’s oceans and other problems caused by higher carbon dioxide concentrations (mongabay).


Cloud seeding on the other hand is the attempt to change the amount or type of precipitation that

falls from the clouds by dispersing substances into the air that serve as cloud condensation. The

usual intent is to increase precipitation, and, in some circumstances, to suppress hail. Silver

iodide and dry ice are the most commonly used substances in cloud seeding. While not a new

technique, cloud seeding for enhancement of rainfall in warm clouds is enjoying a revival based

on some positive indications from research in South Africa, Mexico, and the U.S. It is postulated
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that cloud seeding causes the droplet size spectrum in clouds to become more maritime and less

continental, stimulating rainfall through coalescence. The hygroscopic material most commonly

used is salt (new world).


Seeding of clouds requires that they contain super cooled liquid water colder than zero degrees

Celsius. Introduction of a substance such as silver iodide which has a crystalline structure similar

to that of ice will induce freezing. Dry ice or propane expansion cools the air to such an extent

that ice crystals can nucleate spontaneously from the vapor phase. When ice particles form in

super cooled clouds, this fact allows the ice particles to grow at the expense of liquid droplets. If

there is sufficient growth, the particles become heavy enough to fall as snow or rain from clouds

that otherwise would produce no precipitation. Seeding of warm season 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. For release by aircraft,

silver iodide flares are ignited and dispersed as an aircraft flies through a cloud. When released

by devices on the ground, the fine particles are downwind and upwards by air currents after

release (new world).


Many countries have used and seen success with cloud seeding. The largest seeding system in

the world is that of the Peoples Republic of China, which believes that it increases the amount of

rain over several increasingly arid regions by firing silver iodide rockets into the sky where water

is desired. In the United States, cloud seeding is used to increase precipitation in areas

experiencing drought. Cloud seeding is also occasionally used by major ski resorts to induce
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snowfall. A number of commercial companies offer weather modification services centered on

cloud seeding. Cloud seeding has also been used in Australia where rainfall was increased by 30

percent in autumn (new world).


Although cloud seeding has been shown to be effective in altering cloud structure and size, and

converting cloud water to ice particles, it is more controversial whether cloud seeding increases

the amount of precipitation to reach the ground. Part of the problem is that it is difficult to

discern how much precipitation would have occurred had the cloud not been seeded. The

American Meteorological Society states that there is statistical evidence for seasonal

precipitation increases of about 10 percent with cloud seeding (new world).


Overall the best solution for mitigating drought and minimizing its impacts on the environment

and the economy is to educate the public on how to conserve water in areas of extreme heat and

dry conditions with little rain or snowfall and to continue to use limited or non-renewable

resources responsibly and sustainably. By clearing less forest countries lessen the risk of

desertification and poor soil quality. By conserving water by not overwatering plants or water

logging farm fields the soil will not erode and cause seeds or soil nutrients to wash or blow away

or evaporate causing farmers to abandon farmland which leaves vast areas of dry, uncultivatable

fields open to dust bowl like conditions. And by not polluting waterways, rivers and the ground

with chemicals, pesticides, and non decomposing waste, the environment, ecosystems and

natural habitats of living and non living organisms will flourish and not be destroyed or cause

long lasting consequences that can affect both humans and plants, animals and organisms. By

using non-renewable resources sustainably there will be less fossil fuel polluting the air and
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water, less garbage in landfills and sewer systems, and less poverty and hunger in the world all

leading to less chance of a major drought.


Drought mitigation needs the support of world government, environmental agencies like the EPA

and USDA, scientists, biologists, environmentalists, conservationists like the NWF and U.S.

Forest Service, geologists, and most of all the general consumer. All of these groups, agencies

and individuals need to work together to protect the environment and conserve water and use

limited resources in a responsible way in order to keep the earth from drying up and to prevent

massive droughts. Ultimately the responsibility lies with the government to pass policies and

enforce laws regarding water conservation, pollution, farming practices, deforestation, global

warming and transportation regulations. Without these policies and regulations in place

likelihood of a massive drought or droughts occurring in several regions on earth is almost

guaranteed. Plans need to be put in place by legislation and federal, state, and local agencies that

monitor, assess, and mitigate the risks of droughts occurring and the impacts they will have on

the environment and the economy if they occur. These plans need to include educating the

consumer and businesses on how to better use resources, conserve water and reduce the planets

ecological footprint. They need to address energy conservation, alternative transportation

methods and environmentally safe chemicals for farming and industry. The government overall

must implement these policies and laws but it is up to consumers and businesses to comply with

them and take measures to protect the environment from unsustainable practices that could cause

massive droughts in the future.


In conclusion, even if all these laws, regulations, plans, policies and acts are implemented and

even if governments, agencies, businesses and consumers act responsibly and sustainably in
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protecting the environment, consuming less resources, conserve energy and water and preserve

our wetlands, natural forests and wildlife habitats, one thing is still certain, the issue of drought

and how to mitigate it and minimize its impact on the environment and the economy will be

debated for decades to come. There is no real solution to this natural occurrence and the problem

runs deeper than politics or research. There have been many opinions and suggestions by many

brilliant minds on what to do to mitigate this occurrence and how to lessen its impact on human

and non human lives but in the end it might just come down to Mother Nature to decide if and

when this phenomena will end. In the meantime the world will simply need to find better ways to

deal with Drought.
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DOCUMENT INFO
Description: The planet is gradually getting hotter and dryer today than it has ever been before in history. Scientists from the Intergovernmental Panel on Climate carrying out global warming research have recently predicted that average global temperatures could increase between 1.4 and 5.8 degrees Celsius by the year 2100 (live science). The scientific consensus on climatic changes related to global warming is that the average temperature of the earth has risen 0.4 and 0.8 degrees over the past 100 years (live science). The increased volumes of carbon dioxide and other greenhouse gases released by the burning of fossil fuels, land clearing, agriculture, and other human activities, are believed to be the primary sources of the global warming that has occurred over the past 50 years (live science). Global warming is the term used to describe a gradual increase in the average temperature of the earth’s atmosphere and its oceans (live science). Changes resulting from global warming may include rising sea levels due to the melting of the polar ice caps, as well as an increase in occurrence and severity of storms and a major drought in several parts of the world. Of all the major effects of climate change that can occur drought is by far the most severe and most damaging of all of these live science). Although many scientists and people downplay or exaggerate the effects of a major drought, it is fast becoming a reality for farmers around the world and can have a major impact on the landscape, water supply and food supply that’s needed and used in peoples everyday lives. A major drought can cause food shortages, increased food prices, loss of wildlife habitat, environmental and social problems. To truly understand the effects drought has on the environment and the world as a whole, one must understand what drought really is and the climate forces that can cause it to occur (Bean).