A portable temperature-chlorinity bridge for estuarine investigations and sea water analysis

Abstract

An instrument for the measurement of temperature and chlorinity of water in situ is described. A thermistor is used for temperature measurement, and an electrical conductivity cell, the temperature coefficient of which is compensated by means of the thermistor, is used for chlorinity. The instrument is direct reading, with ranges of 0-30° C for temperature and 0-16 p.p.t. (parts per thousand) and 16-20 p.p.t. for chlorinity. The accuracy is ±0.1° C for temperature, and ±0.05 p.p.t. for chlorinity on the higher range. When used in the laboratory as a transfer instrument, an accuracy of ±0.02 p.p.t. in chlorinity can be obtained.