 |
Desertification
As warmer temperatures affect the earth, areas away from the arctic region that were once able to support agriculture, or natural vegetation, are turning into desert. The harshest effects are found in West Africa, particularly the sub-Saharan regions. Rainfall is becoming scarcer, sometimes years separate the appearance of rain, and soil which is already poor becomes less able to support agriculture. Many of the countries affected do not have the resources to reverse this effect on the soil.
Desertification is a more widespread problem than sub-Saharan Africa alone. It is estimated that up to 50% of the world’s land surfaces are suffering from this process (look at the map to the different levels of vulnerability to desertification). Places such as the Mediterranean coast are also feeling the effects. Countries like Israel and Greece, on the easterly shores of the Mediterranean Sea are suffering from water shortages. Sorting out these shortages is a much bigger problem than one country alone can solve.
As the earth’s population rises, and demand for water increases, the water shortage will obviously get worse as demand outstrips supply. This is being made worse in some parts of the world by problems caused by disputes about who has the right to use water from certain rivers or lakes. Many rivers actually mark the border between one country and another, or a river may run through one country into another. Disputes arise over who has the right to the water in these situations. What if one country upstream of another blocks the supply, to create reservoirs for its own use - what about the supply to the downstream country?
The decline of the Aral Sea
The Aral Sea is landlocked, and found between Kazakhstan and Uzbekistan in Central Asia. Over 50 years ago, when the Aral Sea was in the Soviet Union, water rivers flowing into the Aral Sea began to be diverted, to irrigate the land to allow agriculture to develop. This reduced the amount of water entering the Sea, and so over time it has shrunk, as less water enters it each year than is lost through evaporation.
Today it is less than a quarter of the size it was in the 1960s. In 15 to 20 years it might have vanished altogether. Although the problem of the disappearing sea began when people started diverting water from flowing into it, global climate change has also caused more evaporation, and less rainfall, making the problem worse. However, it is human misuse of natural resources that is the major factor of the Sea’s decline.
|
|
 Top |
|
|
|
|
|
 | How would you try to solve a dispute between countries over a water supply? |
|
| How would water shortages affect your community? |
|
| How could you make a positive contribution towards reducing your / your community’s water usage? |
|
|
|
|
|