Thermoclines

Thermoclines are layers in the water of distinct temperature. They are especially relevant depth sounders as thermoclines can create a Sonar reflections due to the density of the differing water temperatures. Typically a thermocline will appear as a continuous band across the display at some distance above the seabed or river bottom.

Thermoclines are of interest to anglers because Fish will suspend above or below the thermocline as they seek out optimum temperature and oxygen levels.