Can Raymarine fishfinding products display thermoclines?

[Chuck - Raymarine - Moderator]

Can Raymarine fishfinding products display thermoclines?

In temperature terms, oceans and lakes can be thought of in different layers; a mixed layer and a colder deep layer, separated by a thermocline layer, where there is an abrupt change in temperature. The thermocline attracts additional marine life and small particles of debris, reducing the accuracy of fishfinder sonars, as shown below. Configuring a fishfinder to permit manual adjustment to Gain an then increasing the Gain level may permit thermoclines to be more easlily located. Should a thermocline reflect sufficient sonar energy, then a fishfinder or depth instrument may report the depth of the thermocline instead of the actual depth to the bottom. Should a fishfinder be configured for automatic depth ranging, then the fishfinder's depth range will be adjusted to position the thermocline near the bottom of the fishfinder plot. Should this condition occur, then the fishfinder may be configured for manual depth ranging. The depth range would be configured to a depth range which is slightly greater than the charted depth for the location in which the vessel is operating.




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