Accuracy limitations on Brillouin lidar measurements of temperature and sound speed in the ocean

Department of Physics, Texas A&M University, College Station, Texas 77843, USA.
Applied Optics (Impact Factor: 1.69). 10/1997; 36(27):6887-94. DOI: 10.1364/AO.36.006887
Source: PubMed

ABSTRACT There are five mutually dependent variables relevant to Brillouin lidar measurements of temperature and sound speed in the ocean; they are (1) the Brillouin shift, (2) the sound speed, (3) the index of refraction, (4) the temperature, and (5) the salinity. We use three well-known relations to analyze rigorously the interdependence of these five variables. Clearly, a Brillouin shift measurement does not provide a stand-alone determination of temperature or sound speed; one more variable or one more relation must be known. The use of mean values of salinity that have been obtained by an analysis of a large set of historical in situ data is considered for this additional relation.

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