The results of studies of metrological characteristics YSI CastAway-CTD profilograph
https://doi.org/10.36038/2307-3497-2021-184-125-139
Abstract
The results of laboratory experiments to study the metrological characteristics of the YSI CastAway-CTD profilograph are discussed. The factors determining the combined standard uncertainty (CSU) of the calibration of temperature and conductivity sensors are considered. Systematic deviations in CastAway-CTD sensor readings are determined and the temporal drift limits of their calibration characteristics are estimated. To eliminate the systematic effect in the temperature and conductivity data, correcting equations of the third order were used. Estimates of the expanded CSU after correcting the CTD data (the ranges: –1.6 ≤T≤ 30 °C and 27 ≤С≤ 57 mS/cm) did not exceed the values stated by the manufacturer. It is shown that the CastAway-CTD data is affected by the thermal inertia of its body (TIB), therefore TIB is an important metrological characteristic of the profilograph, which can distort the stratification of the studied water masses.
About the Authors
A. N. Ramazin
Russian Federal Research Institute of Fisheries and Oceanography (VNIRO)
Russian Federation
Russian Federation
Moscow
A. Yu. Lazaryuk
V. I. Il’ichev Pacific Oceanological Institute («POI FEB RAS»)
Russian Federation
Russian Federation
Vladivostok
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Review
For citations:
Ramazin A.N., Lazaryuk A.Yu. The results of studies of metrological characteristics YSI CastAway-CTD profilograph. Trudy VNIRO. 2021;184:125-139. (In Russ.) https://doi.org/10.36038/2307-3497-2021-184-125-139
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