On the Accuracy of Distance Estimates Based on Sound Signal Propagation Time on the Arctic Shelf.

Applying numerical modelling approach the accuracy in determining the distance between underwater sound sources and receivers is assessed at a range of several kilometers from each other in the Kara Sea in autumn. It is suggested that the main source of errors in determining the distance is the lack of accurate data on the vertical sound speed profile along the acoustic signal propagation path. Data from September and November were analyzed, in the interval between which significant changes in the profile take place, when the vertical sound speed gradient changes from negative to positive. Characteristic values of sound speed variations were obtained by statistical processing of hydrological data taken from the World Ocean Database. The results are important for analyzing the capabilities of underwater acoustic navigation. [ABSTRACT FROM AUTHOR]