Access to safe water and food is linked to global, regional and local climate changes. In some areas, swift changes have entailed serious health-related consequences. An alarming example is found in the Aral Sea area of Central Asia.
The Aral Sea area, located on the border between Kazakhstan and Uzbekistan, was once the fourth largest inland sea in the world. Since the 1960s, water volume has been reduced by a factor of fourteen. Tributary water to the Aral Sea derives from the rivers the Amu Darya originating in Tajikistan, and the Syr Darya originating in Kyrgyzstan. Early in the 20th-century demand for river water to supply local agriculture, primarily the cotton industry led to the construction of irrigation systems.
A highly inefficient system for water allocation combined with excessive resource exploration was the result. Subsequent failure to maintain infrastructure, in tandem with large emissions of pollutants have had serious consequences for people inhabiting the areas around the Aral Sea.
After the Soviet Union created collective farms in 1929, water usage increased and the Aral Sea started shrinking. By 1987, the lake had split into two separate parts. Water distribution was complicated by the collapse of the Soviet Union in 1991, creating several new countries with separate water policies.
Uzbekistan is today one of the world’s largest cotton producers and needs large amounts of water to sustain production. A simultaneous population increase complicates the severe water shortage in the area and contributes to the environmental disaster, evident by the disappearance of the Aral Sea. Its role as an important food source is impaired due to increased salinity.
In 1983 more than 20 different fish species were declared extinct. River deltas have been replaced by desert, mediating a replacement of the original flora with hardier plants. Local climate change has occurred simultaneously with the disappearance of water. Formerly hot, humid regions are acquiring a cold, dry desert climate.
No rivers flow out of the Aral Sea; water disappears through evaporation. Before construction of the excessive irrigation systems, the water level was kept stable by inflow from the Amu Darya and the Syr Darya. As human use of river water has increased, the composition of lake water has changed. Salt concentration has increased tenfold and local groundwater has a salt concentration reaching 6 g/L.
This is six times higher than the concentration considered safe by WHO. Naturally, local inhabitants are exposed to saline water and in 2000 only 32 % had access to safe drinking water. An increased frequency of storms carries 43 million tons of dust and sand from the dried-out sea floor through the air yearly
With the disappearance of rivers flowing into the Aral Sea area, drinking water is a highly valuable resource. Water shortage and contamination of stored drinking water are important causes of faecal-oral transmission of disease in Aral Sea area households. Accordingly, hepatitis A and diarrhoeal disease are frequently reported.
At the turn of the century, the infant death rate due to diarrhoea was twice that of bordering areas. Parasitic infections and tuberculosis are also a challenge. Some claim that the high incidence of disease, including tuberculosis, is related to increased poverty, resulting in poorer personal hygiene and malnutrition. Indeed, multi-drug resistant tuberculosis presents a significant challenge in this region.
An alarming signal
As we have seen, global, regional and local climate change can have negative consequences for human health. The Aral Sea disaster shows the result of the short-sighted human exploitation of nature and is an alarming signal, indicating that all human activities with potential climate effects must be carefully thought through.