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).
Similar content being viewed by others
References
Bailey, R., H. Phillips and G. Meyers (1989): Relevance to TOGA of systematic XBT errors. p. 775–784. In Proc. of the Western Pacific International Meeting and Workshop on TOGA COARE, ed. by J. Picaut and R. Lukas, Noumea.
Hanawa, K. and H. Yoritaka (1987): Detection of systematic errors in XBT data and their correction. J. Oceanogr. Soc. Japan, 43, 68–76.
Hanawa, K. and Y. Yoshikawa (1991): Reexamination of the depth error in XBT data. J. Atmos. Ocean. Tech., 8(3), 422–429.
Hanawa, K., P. Rual, R. Bailey, A. Sy and M. Szabados (1995): A new depth-time equation for Sippican or TSK T-7, T-6 and T-4 expendable bathythermographs (XBT). Deep-Sea Res., 42(8), 1423–1451.
Hanawa, K., Y. Yoshikawa and T. Taneda (1996): TOLEX-ADCP monitoring. Geophys. Res. Lett., 23(18), 2429–2432.
Kitagawa, S., T. Taira and T. Teramoto (1981): A digital data logger for the XBT. La mer, 19, 165–170 (in Japanese with English abstract and captions).
Kizu, S. and K. Hanawa (2002): Start-up transient of XBT measurement by three types of Japanese recorder system. Deep-Sea Res. (in press).
Roemmich, D. and B. Cornuelle (1987): Digitization and calibration of the expendable bathythermograph. Deep-Sea Res., 34(2), 299–307.
Thadathil, P., A. K. Ghosh, J. Pattanaik and L. Ratnakaran (1999): A quality-control procedure for surface temperature and surface layer inversion in the XBT data archive from the Indian Ocean. J. Atmos. Ocean. Tech., 16, 980–982.
UNESCO (1997): First Session of the Joint IOC-WMO IGOSS Ship-of-Opportunity Programme Implementation Panel. Cape Town, South Africa, 16–18 April 1997.
Wright, D. M. (1991): Field evaluation of the XBT bowing phenomenon. OOD Data Report 91–2, Ocean Observations Division/Office of Ocean Services, National Ocean Service, NOAA, 12 pp.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Kizu, S., Hanawa, K. Recorder-Dependent Temperature Error of Expendable Bathythermograph. Journal of Oceanography 58, 469–476 (2002). https://doi.org/10.1023/A:1021261214950
Published:
Issue Date:
DOI: https://doi.org/10.1023/A:1021261214950