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Environment
The SWellEx test site has been extensively studied. An impressively detailed geoacoustic database and model exists for the region. In addition, a CTD survey was conducted during the SWellEx-96 Experiment to provide water column sound speed data.
Waveguide
For the waveguide, the water depth is assumed to be the water depth at the array for range-independent processing. The seafloor is composed first of a 23.5 m thick sediment layer with a density of 1.76 g/cm^3 and an compressional attenuation of 0.2 dB/kmHz. The top of the sediment layer has a compressional sound speed of 1572.368 m/s while the bottom of the sediment layer has a compressional sound speed of 1593.016 m/s. Below the sediment lay an 800 m thick mudstone layer with a density of 2.06 g/cm^3 and an attenuation of 0.06 dB/kmHz. The top and bottom sound speeds of the mudstone layer are 1881 m/s and 3245 m/s, respectively. The geoacoustic model is completed by a halfspace with a density of 2.66 g/cm^3, an attenuation of 0.020 dB/kmHz, and a compressional sound speed of 5200 m/s.
Water Column Sound Speed
The CTD data from the SWellEx-96 Experiment was salinity-despiked and depth-interpolated every 0.5 m, yielding 51 final CTD casts. Each CTD data file contains five columns: (1) depth [m], (2) temperature [Deg C], (3) salinity (PSU), (4) sound speed (m/sec), and (5) sigma-t.
Note: The times listed below are local times (GMT - 7 hours). Add 7 hours to the listed time to convert to GMT. For a tarball containing ASCII versions of the CTD information below as well as the CTD data, click here to download the file "ctds.tar.gz" (256 KB).
