Fig. 7

Bellhop model predicts transmission loss and ray propagation on a DOY 250 (summer stratified conditions) with transmitter sitting at 11 m, b DOY 250 with transmitter sitting at 50 m, c DOY 300 (fall isothermal conditions) with transmitter sitting at 11 m, and d DOY 300 with transmitter sitting at 50 m. Two thresholds of transmission loss of 63 dB and 68 dB are indicated with grey line and black line, respectively. The faint dashed lines are a selection of the trajectories of acoustic rays used by the Bellhop model—the key feature is they are straight lines in isothermal conditions and they bend in stratified conditions, and that they reflect from boundaries