Which term describes a layer where temperature changes rapidly with depth?

Which term describes a layer where temperature changes rapidly with depth?

• A. Surface zone
• B. Mixed layer
• C. Thermocline
• D. Deep zone

Answer: (C)

A layer where temperature changes rapidly with depth is the thermocline. This zone sits between the warm, well-mixed surface layer and the deeper, colder waters. The surface layer is stirred by wind and waves, so its temperature stays nearly uniform with depth, while the deep zone remains consistently cold with only small changes as you go deeper. In tropical oceans the thermocline is especially pronounced, forming a sharp transition between these layers; in polar regions it can be much weaker or absent.

A layer where temperature changes rapidly with depth is the thermocline. This zone sits between the warm, well-mixed surface layer and the deeper, colder waters. The surface layer is stirred by wind and waves, so its temperature stays nearly uniform with depth, while the deep zone remains consistently cold with only small changes as you go deeper. In tropical oceans the thermocline is especially pronounced, forming a sharp transition between these layers; in polar regions it can be much weaker or absent.