Continuously sensing of water temperature in a lake using acoustic tomography method

Continuously sensing of water temperature is of critical importance to water environment, fluid dynamic and water resources researches. Coastal acoustic tomography (CAT) is a remote sensing technique in spatial temperature distribution estimating and has been widely used in many coastal regions. Continuous observations of water temperature in small-scale waters with distance less than 1 km are seldom conducted, as it is difficult to get high-resolution observation results. Here, a horizontal temperature field within 300 m distance was mapped in a sound transmission experiment with three 50 kHz CAT systems. The maximum inversion error temperature for the horizontal temperature field was 0.09°C. The root-mean-square error between the CAT-observed and range-averaged temperature that were calculated from one-way travel time data along three transmission paths were 0.03°C, 0.028°C and 0.043°C, respectively. The obtained results confirmed that CAT can be used in recovering the horizontal distributions of water temperature fields in lake.