Calculated Sound Speed

Calculating sound speed
from XBT temperature profiles

>> Climatology Assisted Calculated Sound Speed

vs

>> Conventional sound speed calculation

New Advanced
Climatology Assisted Calculated Sound Speed

Calculating sound speed from XBT temperatures is a standard procedure. This typically involves setting a particular fixed value of salinity to be used in the calculations, usually 35 psu. This assumes salinity deviation will not lead to unacceptable sound speed errors.

Turo XBT software uses advanced algorithms to extract a salinity profile from the climatology database - a salinity profile for the given latitude and longitude and for the given seasonal time of year. This salinity profile is then used with the XBT temperature profile to derive a sound speed profile.

Operator selectable options enable either climatology assisted or standard fixed value calculations.

The following clearly illustrates the potential improvements. In this example at 200 metres depth the standard method is improved upon by >1 m/sec and possible distortion is improved over the whole profile.

sound speed calculation uses salinity from climatology	sound speed calculation uses fixed salinity set to 35 psu	difference between between standard and climatology assisted methods