Final answer:
The physical change in the Aral Sea is that the smaller, shallower, upper portion remains more intact after a dam was added between the north and south sections.
Step-by-step explanation:
One physical change that can be seen in the Aral Sea since humans altered the flow is the smaller, shallower, upper portion remains more intact after a dam was added between the north and south sections. This is true. Before the alteration, the Aral Sea was a large, deep body of water, but due to the redirection of rivers for irrigation purposes, the sea has shrunk significantly. The addition of a dam has further restricted the flow of water, causing the upper portion to appear relatively more intact compared to the heavily impacted southern part.
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