Sunday, March 15, 2015

Aral Sea Dust Storm - NASA Sattelite Images

Source: Earth Observatory NASA Aral Sea  Jeff Schmaltz

NASA image showing dust plumes  coming up from desiccated lakebed  of the Aral Sea. NASA’s Aqua satellite captured this true-color image using the MODIS (Moderate Resolution Imaging Spectro-Radiometer) on March 26, 2010.

The pale beige plume of dust blows from the sediments of the South Aral Sea toward the southeast, along the Kazakhstan-Uzbekistan border.

Once counted among the world’s largest inland lakes, the Aral Sea shrank dramatically in the second half of the twentieth century after the Soviet Union tapped the rivers feeding the sea for irrigation projects. As the Aral Sea’s decline continues and the water levels fell, the sea separated into the North Aral Sea and the South Aral Sea, and the southern portion further divided into eastern and western lobes.A dam has helped to partially restore the North Aral but the same project has led to continued decline of the South Aral Sea. The mottled appearance of the North Aral Sea in this image probably results from a coating of lingering winter ice.
 
The retreat has left behind large expanses of dry lakebed sediments prone to forming dust plumes. In addition, local sediments had become a repository for salt, fertilizers, and pesticides frequently used in irrigated farming. The increased frequency of dust storms combined with the chemicals contained in the lakebed sediments have raised concerns about the impact of Aral Sea dust storms on human health in the region.


Reference:

Wiggs, G.F., O’Hara, S.L., Wegerdt, J., Van der Meer, J., Small, I., Hubbard, R. (2003). The Dynamics and Characteristics of Aeolian Dust in Dryland Central Asia: Possible Impacts on Human Exposure and Respiratory Health in the Aral Sea Basin. The Geographical Journal, 169(2), 142–157.