1. A system for mapping a thermocline in a body of fluid, comprising: at least one thermocline detection and monitoring module (TDMM); a persistent data storage module; and a plurality of distributed sensors, including intelligent sensors, connected with the at least one thermocline detection and monitoring module and the persistent data storage module by one or more control-level programming and communication methods, wherein the at least one thermocline detection and monitoring module monitors the thermocline by collecting measurement data from the plurality of sensors at sampling intervals, fuses measurement data to capture thermocline changes as events, correlates measurement data and events, stores measurement data in the persistent data storage module along with previously acquired measurement data for comparison and tracking, characterizes the thermocline as a function of spatial location, depth, and time, creates and maintains reports that describe the thermocline characteristics, status, trends, and provides multimodal notifications of events to different users.