Earth and Space Sciences Regents, August 2026, question 29
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What the figure shows
The passage says the Aral Sea in arid central Asia is fed by the Amu Darya and Syr Darya rivers, which were diverted for irrigation in the 1960s, so the sea shrank. The Kok-Aral Dam, completed in 2005, split it into the North Aral Sea and the South Aral Sea and was designed to keep water from flowing from the North Aral Sea to the South Aral Sea. Maps of 1960 and 2020 show the sea shrinking into several smaller water bodies, with the Kok Aral Dam at the south end of the North Aral Sea, near where the Syr Darya River enters. The question gives a statement with three blanks and a table of four rows: A is the change in water level of the North Aral Sea (a decrease or an increase), B is the change in sediment (an increase or a decrease), and C is deposition upstream or erosion downstream of the dam.
How to think about it
Fill the blanks in order. First use the passage to decide what holding water back with a dam does to the water level on the side that keeps the water. Then think about how a river's speed changes where it flows into deeper, still water, and what a change in speed does to the sediment the river carries.
Which row in the table below contains a set of terms that correctly completes the statement below? Construction of the Kok-Aral Dam in 2005 caused A in the water level of the North Aral Sea, causing B in sediment C of the dam by the river. Row A B C