closed lake

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June 24, 2026

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A closed lake is a body of water that has no outlets, either above or below the surface. Water is only lost from these lakes through evaporation. This process can lead to an increase in the lake's salinity, especially if the incoming water is less saline than the lake itself.1

Closed lakes are most common in semiarid regions where the balance between water input (precipitation and inflows) and output (evaporation and seepage) favors evaporation. Examples of closed lakes include the Aral Sea, which has significantly shrunk due to water diversion for irrigation, leading to increased salinity and environmental changes.23

While lakes play a small quantitative role in the global hydrologic cycle, freshwater lakes hold over 98% of the surface water available for use. Major lakes like Baikal, Tanganyika, and Superior contain vast amounts of water.3

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sedimentary rock
Nonmarine environment
…the nonmarine environment occurs in closed lakes—i.e., those without outlet—in arid and semiarid regions. Such lakes form in closed interior basins or shallow depressions on land where drainage is internal and runoff does not reach the sea. If water depths are shallow or, more typically, somewhat ephemeral, the term playa…
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…the nonmarine environment occurs in closed lakes—i.e., those without outlet—in arid and semiarid regions. Such lakes form in closed interior basins or shallow depressions on land where drainage is internal and runoff does not reach the sea. If water depths are shallow or, more typically, somewhat ephemeral, the term playa…
Read More