Journal of Oceanography

, Volume 54, Issue 4, pp 373–380 | Cite as

Preliminary results of in-situ XCTD/CTD comparison test

  • Keisuke Mizuno
  • Tomowo Watanabe
Short Contribution


The current status of XCTD manufactured by the Tsurumi Seiki Co. is described based on XCTD/CTD comparison tests conducted in the Pacific and Indian Ocean in November 1996 and January 1997 respectively. The falling rates of used probes are generally consistent and differences between individual probes stay within a small range of +/−5 m through the full depth range (0–1000 m), although the rate is slightly different from the depth-time equation provided by the manufacturer. Temperature and salinity accuracy is estimated to be better than 0.05°C and 0.05 psu respectively. Comparison of vertical temperature/salinity sections of XCTD/CTD constructed separately along a line on which XCTD stations locate midway of CTD stations. The hydrographic structures obtained are generally consistent, and the difference of surface dynamic height (referred to 1000 db) is 0.03 dyn m in RMS.


XCTD VOS depth-time equation measurement error Indian Ocean 


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Copyright information

© The Oceanographic Society of Japan 1998

Authors and Affiliations

  • Keisuke Mizuno
    • 1
  • Tomowo Watanabe
    • 1
  1. 1.National Research Institute of Far Seas FisheriesShimizuJapan

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