Expendable bathythermograph (XBT)

ICDC Project


RESTRICTED only accessable in CEN/MPI net or via CliSAP login  What does that mean?

Data access via file system: /data/icdc/ocean/xbt



Expendable bathyhermograph (XBT) measures temperature down to the depth of about 800 m from a moving ship. Since the late 1960s XBTs contributed the majority of the subsurface temperature measurements in the ocean. However the XBT sample depth is not measured but calculated from the estimated fall-rate. The uncertainties in the fall-rate and the malfunctioning of the acquisition system cause XBT temperatures to be biased. This bias was shown to be comparable in magnitude with the typical decadal-scale temperature variability , so that neglecting this bias can seriously distort our estimates of global ocean climate change. Using original XBT data from the World ocean database WOD09 (Boyer et al., 2009) we provide a data product which includes depth- and temperature-corrected XBT profiles. The correction method is based on the recent study by Gouretski and Reseghetti (2010).


To top


<b>Name</b> <b>Unit</b>
Depth m
Temperature °C

To top

Coverage, temporal and spatial resolution

Period and temporal resolution:

  • 1997 until 2008
  • Daily, different number of profiles of different length obtained during various measurement campaigns

Coverage and spatial resolution:

  • Global (see figure on top of page)
  • Spatial resolution: None, sampling along the cruise tracks depends on measurement campaign
  • Geographic Latitude: -90°N to 90°N
  • Geographic Longitude: 0°E to 360°E
  • Dimension: 1 column x 1 row x N measurements along the vertical profile
  • Altitude: N depths, vertical profiles



To top

Data quality

See Gouretski and Reseghetti, 2010.


To top


Viktor Gouretski

ICDC / CEN / University of Hamburg

email: viktor.gouretski (at) uni-hamburg.de

To top

Data citation

Contact Viktor Gouretski

To top

###BACKLINK###     ###TOPLINK###