14 DAY TRIAL // The Aral Sea, located between Kazakhstan and Uzbekistan, was once one of the four greatest lakes on Earth. Due to a series of irrigation projects undertaken by the Soviet Union in the 1970s, its surface has now declined to a mere fraction of its former glory. A new study shows that the sea may not dry out completely in the near future.
Over the past few decades, the four smaller lakes that were left behind as the sea retreated diminished in size, until one of them disappeared entirely. The Aral Sea once featured 1,534 islands, and covered a surface of 68,000 square kilometers (26,300 square miles)
As the rivers that fed it were diverted, the sea received constantly-diminishing amounts of water. The thriving fish industry that went on on its banks was annihilated, and experts say that the sea, or whatever is left of it, will soon disappear altogether.
The new investigation, based on data collected by NASA satellites, indicates that the Central Asian sea may have a brighter short-term future ahead than first estimated. In other words, it may take longer for it to dry off completely than initially calculated. The final outcome, however, will be the same.
After analyzing records from the NASA Tropical Rainfall Measuring Mission (TRMM) satellite, University of Toledo assistant professor Richard Becker and graduate student Kirk Zmijewski found no change in precipitation levels over the area since 2002.
Data from the NASA Gravity Recovery and Climate Experiment (GRACE) satellite indicate that the entire Aral Sea watershed is losing water at a rate of about 12 to 14 cubic kilometers (2.9 to 3.4 cubic miles) per year, a rate that is just half of that at which the sea itself is drying up.
“That means that roughly half the water lost from the Aral Sea has entirely left the watershed, by evaporation or agricultural uses, but half is upstream within the watershed,” Becker explains.
“Lake-effect precipitation downwind of the Aral Sea has decreased, but precipitation over the sea itself has increased, so that's not changing the whole system,” he adds. The research team published its discoveries in the January 31 issue of the journal Earth Interactions.