Hydrologic Conditions in the Santa Anna and Franz Victoria Troughs

摘要

The optimal source depth for transarctic transmissions and acoustic thermometry over transarctic paths, depends on the sound speed profile at the transmitting site. Furthermore, for analysis and interpretation of acoustic data in the experiment, it is necessary to have information on long-term variations of the sound speed profile in the vicinity of the source. Such variations, like seasonal changes, tidal and internal waves, and intrusions, disturb the modal eigenfunctions and hence the excitation coefficients, which can lead to considerable fluctuations in the modal amplitudes at the receiving site. If these fluctuations are considerable, they may complicate the detection of climatic changes in the mean ice thickness reflected in variations of the sound speed also lead to variations in the modal propagation times, which produce noise in the measurements of climate and basin-scale changes in Arctic water.