The Aral Sea has shrunk to less than half its size since 1985. It receives little water (sometimes none) from the two major rivers that empty into it—the Syr Darya and Amu Darya. Instead, the river water is diverted to support irrigation for the region’s extensive cotton fields. Recently, water scarcity has increased due to a prolonged drought in Central Asia. As the Aral Sea recedes, its former seabed is exposed. The Aral’s sea bed is composed of fine sediments—including fertilizers and other agricultural chemicals—that are easily picked up by the region’s strong winds, creating thick dust storms. The International Space Station crew observed and recorded a large dust storm blowing eastward from the Aral Sea in late June 2001. This image illustrates the strong coupling between human activities (water diversions and irrigation), and rapidly changing land, sea and atmospheric processes—the winds blow across the Sea and pick up dust (former sea bottom sediments) as soon as the blowing air masses hit land.
Published Dec 30, 2001
The shrinking of this once-vast inland lake means winds more frequently pick up dust from the exposed lakebed.
Published Mar 25, 2020
stronauts aboard the International Space Station (ISS) took this image of a major dust storm (image center and right) along the east side of the Aral Sea while passing over central Asia in the spring of 2007. The white, irregular lines along the bottom of the image are salt and clay deposits on the present coastline. The day that the ISS crew shot the image, winds were blowing from the west (lower left).
Published Nov 5, 2007
In the past few centuries, a river in northwestern Canada stopped wandering and assumed a more direct route to the sea.
Published Sep 4, 2012
A satellite image offers inky evidence of the organic-rich freshwater that the Suwannee River delivers to the Gulf of Mexico.
Published Oct 27, 2018
Acquired April 2, 2011, and February 27, 2011, these natural-color images show rising waters on the Kuiseb River, which flowed all the way to the Atlantic Ocean for the first time in decades.
Published Apr 12, 2011
The Ural River is one of the two major rivers (the other is the Volga) that empty into the northern coast of the Caspian Sea, creating extensive wetlands. This image shows details of the Ural’s tree-like (or “digitate”) delta. This type of delta forms naturally when wave action is low, and sediment content in the river is high. New distributary channels form in the delta when the river breaches natural levees created by sediment deposition. The long main channel of the river in this image and several of the distibutary channels are too regular to be entirely natural, however. Like the famous Mississippi River delta in the United States, the Ural River delta has been significantly modified to reduce flooding and divert water.
Published Jun 6, 2005
