Journal of Oceanography

, Volume 58, Issue 3, pp 469–476 | Cite as

Recorder-Dependent Temperature Error of Expendable Bathythermograph

  • Shoichi Kizu
  • Kimio Hanawa

Abstract

The accuracy of temperature measurement by the expendable bathythermograph (XBT) is examined for five types of recorders by comparison with co-located CTD measurements and statistical analysis of temperature profiles including an isothermal layer. A positive temperature error increasing downward is occasionally detected for two types of Japanese recorder which have been commonly used among Japanese oceanographic institutions and marine observatories. This error resembles to that reported by Bailey et al. (1989) and Wright (1991) for a different type of recorders, although its cause is not clearly understood. The irregular occurrence of the error suggests that the problem is not solely due to the recorders but rather by some inconsistency of the whole measuring system including them, an XBT probe and sea water. The error is estimated to increase at a rate of O (0.1°C/100 m), and it could be close to 1°C at the deepest part of the profiles (760 m for Tsurumi T-7).

Expendable bathythermograph XBT temperature measurement VOS monitoring 

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Copyright information

© The Oceanographic Society of Japan 2002

Authors and Affiliations

  • Shoichi Kizu
    • 1
  • Kimio Hanawa
    • 1
  1. 1.Department of Geophysics, Graduate School of ScienceTohoku UniversitySendaiJapan

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