pycnocline

As nouns the difference between pycnocline and chemocline

is that pycnocline is a boundary layer in a body of water between areas of different temperature or salinity while chemocline is the interface between the mixolimnion and monimolimnion in a meromictic lake.

As nouns the difference between pycnocline and halocline

is that pycnocline is a boundary layer in a body of water between areas of different temperature or salinity while halocline is a strong, vertical salinity gradient; the (sometimes indistinct) border between layers of water that contain different amounts of salt.

As nouns the difference between thermocline and pycnocline

is that thermocline is a layer within a body of water or air where the temperature changes rapidly with depth while pycnocline is a boundary layer in a body of water between areas of different temperature or salinity.