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MBT Bias Depth and Temperature Corrections
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Mechanical bathythermograph (MBT) measures temperature down to the depth of 250m from a slowly moving ship. The MBT data is shown to be biased due to systematic errors in depth (pressure) and temperature sensors. Following are a few studies that tried to estimate a correction to the bias in depth and temperature in the MBT measurements.

Ishii, M. and M. Kimoto, 2009: Reevaluation of historical ocean heat content variations with an XBT depth bias correction. J. Oceanogr. 65, 287299, doi:10.1007/s10872-009-0027-7. Ishii and Kimoto corrections.

Levitus, S, J. Antonov, T. Boyer, 2009: Global ocean heat content 1955-2007 in light of recently revealed instrumentation problems. Geophys. Res. Lett. , 36, L07608, doi:10.1029/2008GL037155. Levitus et al. corrections; July, 2019 corrections.

Gouretski, V. and F. Reseghetti, 2010: On depth and temperature biases in bathythermograph data: Development of a new correction scheme based on analysis of a global ocean database. Deep-Sea Research I, Vol. 57(6), pp. 812-834, doi:10.1016/j.dsr.2010.03.011. Gouretski and Reseghetti corrections, updated corrections.

Hamon, M., G. Reverdin, P-Y Le Traon, 2012: Empirical correction of XBT data. Journal of Atmospheric and Oceanic Technology, doi:10.1175/JTECH-D-11-00129.1, in press. Hamon et al. corrections.

A similar page on the XBT bias on temperature and depth corrections is available on XBT bias correction page.