Unit 7: Energy and water - water shortages

Water shortages

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

Causes

Source: http://www.worldwildlife.org/

POLLUTION

Water pollution comes from many sources including pesticides and fertilizers that wash away from farms, untreated human waste water, and industrial waste. Even groundwater is not safe from pollution, as many pollutants can leach into underground aquifers. Some effects are immediate, as when harmful bacteria from human waste contaminate water and make it unfit to drink or swim in. In other instances—such as toxic substances from industrial processes—it may take years to build up in the environment and food chain before their effects are fully recognized.

AGRICULTURE

Agriculture uses 70% of the world’s accessible freshwater, but some 60% of this is wasted due to leaky irrigation systems, inefficient application methods as well as the cultivation of crops that are too thirsty for the environment in which they are grown. This wasteful use of water is drying out rivers, lakes and underground aquifers. Many countries that produce large amounts of food—including India, China, Australia, Spain and the United States—have reached or are close to reaching their water resource limits. Added to these thirsty crops are the fact that agriculture also generates considerable freshwater pollution – both through fertilizers as well as pesticides – all of which affect both humans and other species.

POPULATION GROWTH

In the last 50 years, the human population has more than doubled. This rapid growth— with its accompanying economic development and industrialization—has transformed water ecosystems around the world and resulted in a massive loss of biodiversity. Today, 41% of the world’s population lives in river basins that are under water stress. Concern about water availability grows as freshwater use continues at unsustainable levels. Furthermore, these new faces also need food, shelter, and clothing, thus resulting in additional pressure on freshwater through the production of commodities and energy.

CLIMATE CHANGE

As humans continue to pump more carbon dioxide and other greenhouse gases into the atmosphere, patterns of weather and water will change around the world. Droughts will become more common in some places, floods in others. Glaciers and snow packs will disappear in some areas, affecting the freshwater supplies to those downstream communities. These changes will combine to make less water available for agriculture, energy generation, cities and ecosystems around the world.

Source: http://www.worldwildlife.org/threats/water-scarcity

The impacts of lack of access to clean water

Source: https://www.youtube.com/watch?v=BCHhwxvQqxg