Population size has been a key driving factor in water supply scarcity. The water consumption patterns across the global vary making the water scarcity and depletion of its sources worse. The world population is skyrocketing. This implies that there will be critical shortfalls of water resources translating into a greater misery for future generation.
Demographers conclude that the population transitions result from increasing material prosperity such as better nutrition, sanitation, higher literacy rates, the emancipation of women, and increasing access to contraceptives. The UN projects that the worlds total population will grow from the current 6 billion to 8 billion by the year 2025.
Regional population growth varies widely. For instance, Western Europes population will grow with a small margin, but China will grow by 16 per cent in the year 2025 while North America will grow by 12 per cent, and Africa will take the lead at 18 percent.
This uneven growth of population causes uneven demand for water supplies, both for human consumption and other uses. The world population is mainly high in urban centers. The implication is that as population size continues to grow, the demand for water also grows leading to depletion of natural water sources.
Global warming, particular consumption of fossil fuels and hydrocarbons, release a number of gases that impede the escape of heat from the surface of the earth into space. Concentrations of these gases increase the temperature of the surface of the planet. The earth relies on the naturally occurring greenhouse effects in order to sustain most of its life (Homer-Dixon, 1999).
The global mean surface temperature has risen up between 0.3 and 0.6 degrees Celsius. The decade of the year 2000 has experienced the warmest temperature in the records. Interestingly, scientists have begun to understand the positive counteracting effects on global warming. Human emissions of sulfate aerosols reflect some sunlight back into space particular in heavily industrialized regions.
Conversely, studies show noticeable human effects on global climate. The evidences gathered from analysis of ice-core, analysis of ocean circulation, sea temperature and earths temperature show that the earths surface temperature is on the increase around the world.
We must begin to wonder what effects of global warming might do in the next few decades to natural resources. Obviously, the sea levels will rise principally from thermal expansion of sea water. The seasonal temperatures differences in some areas will decrease. Subsequently, winter will become warm and abnormal hot days will be common. Finally, the water cycles will become more vigorous.
These changes will result into floods, droughts and heat waves, which will have severe effects on water supplies. Further, changes in global warming will have adverse effects on agricultural production in both developed and developing nations. Other effects may result into multiple critical impacts on agricultural resources such as depletion and degrading of freshwater and cropland supplies.
The ongoing climate talk in Durban, South Africa is focusing on serious issues of the global warming. The poor nations want the developed states to take responsibilities for emission of the large amount of hydrocarbons into the atmosphere. They simply want the Kyoto Protocol of 1997 renewed in order to combat global warming and protect the environment. Analysts see the solution to lies in the green sources of energy.
Tropical deforestation is causing severe consequences on water supplies. The records estimate that tropical forest area is about 1.2 billion hectares in the world. Tropical deforestation varies widely from region to region. The UN Food and Agricultural Organization (FAO) estimated that the high rate of tropical deforestation we experienced in the early 1980s is ever increasing. This action mainly affects easily accessible moist and deciduous forests and rain forests (Grover, 2006).
Human tendency of encroachments to clear forest areas for other purposes have created a situation of water scarcity. FAO estimates that between 1960 an 1990 Asia lost a third of its tropical forests, while Latin America and Africa lost a fifth of their tropical forests. The damages to tropical rainforest are more alarming than what statistics suggest.
This is because statistics do not account for widespread degradations and fragmentations that have negative impacts on the resilience and biodiversity of the tropical forest ecosystems. The scramble for forest resources showed Japan set up several factories in order to exploit forest resources. The log exporting companies did not take any initiatives of reforestation of the depleted forest cover. The point is tropical forests are the main sources of freshwater for human consumption. Any depletion results into water scarcity (Hassenzahl, Linda and Peter, 2008).
There are large disparities in water availability that exist in all societies. Freshwater scarcity is now one of the chief issues of 21st century. Water scarcity problem occurs as a result of rising demands. Further to this, water pollution and depletion are also becoming a source of critical concerns. The world population has been experiencing reduce water quality with its severe consequences directly on human health through waterborne diseases.
In the year 1999, the world population withdrew about 4,250 cubic kilometers of freshwater from its various sources and returned about 1,700 cubic kilometers to waters in its polluted forms. Water exists in great abundance in most regions. However, this water is either in its polluted form or too saline for human consumptions.
The current trends show that regions such as India, Europe, the US and China are depleting their local rivers runoff. In arid areas, rapid population increase is threatening water availability and supplies. The world is most likely to restrict water use in irrigated agricultural lands. At the same time, urban slums and squatters also have insufficient water supply for basic hygiene, while rural families trek long distances in search of water (Sergi and Barcelo, 2010).
Despite water scarcity, families in Middle East and Africa are still expanding their sizes rapidly, and freshwater is already a scarce resource. Water stress and chronic absence is rising around the world. Therefore, water has become a source of contention and conflicts among certain groups and societies in the world.
Scholars explain conflicts due to scarcity of resources under . They are interstate resource wars caused by national interests on shrinking natural resources. Water provides a significant example. In this case, river water has become a source of conflicts among many nations. This is because river water cross boundaries and its access can be marred by another nations actions.
The global water scarcity and stress are getting much worse. Downstream countries are highly dependent on river water for their national courses. This is the case of Egypt and River Nile. Ethiopia had threatened to restrict the flow of Nile water. Subsequently, Egypt was willing to defend that act with its military power to ensure an adequate supply of Nile water.
The Nile Treaty will resolve these conflicts. India has built a huge dam (Farakka Barrage) across Ganges with severe effects on the downstream Bangladeshs fisheries, agriculture and domestic use. Bangladesh is weak and more often pleads with India to release more water.
Historically, water wars are always internal affairs of states. For instance, the pastoral communities of Kenya fight for scarce water for their livestock. Rarely are there wars involving water across international borders, but there are great deals of water conflicts within states.
Governments build large dams in order to control water scarcity. This move results into problems of disruption and relocation. Therefore, conflicts occur between the government and affected people of the river banks (Evans, 2000).
The contribution of water reuse and treatment to water resources management is still extensively underdeveloped across the globe. The reasons for underdevelopment vary from technological, lack of long lasting regulations, resistance to change irrigation methods to economically water efficient applications. We must incorporate water reuse into global water resources management.
The world should adopt different strategies to deal with water scarcity. For instance, there are different strategies for safe use of saline water and treated wastewater. Irrigated lands should adopt supplemental irrigation with saline water in areas of high seasonal rainfall, and apply agricultural rotations in crop production with crops of different water quality tolerance. Alternatively, farmers can manage irrigation by applying frequency and amount controls in farmlands.