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Chinese Journal of Oceanology and Limnology

, Volume 9, Issue 4, pp 375–385 | Cite as

Effects of surface waves and ship heave-and-roll on CTD data and processing method for CTD data

  • Zhang Aijun
Article

Abstract

The effects of surface waves and ship heave-and-roll on CTD data are discussed. The heave-and-roll produces spurious step-like structures in the CTD data. Derivation of a formula for calculating the probe's fall speed is discussed. Several current techniques for CTD sensor lag correction are analyzed and compared. It is shown the lag correction procedure presented here, which is based on the Giles-McDougall technique, can be employed to treat CTD data from regions with slow or fast T-S variations, for instance, in strong seasonal thermocline. False salinity spikes or humps in data corrected with this procedure are significantly reduced.

Keywords

Surface Wave Pressure Reading Ship Motion Conductivity Sensor Density Inversion 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

  1. Alexander, S. Y., 1985. An alternative editing technique for oceanographic data.Deep-Sea Res. 32 (12a): 1591–1599.Google Scholar
  2. Fang Xinhua, 1987. On the pretreatment of CTD pressure data.Marine Science Bulletin 6 (1): 86–87 (in Chinese)Google Scholar
  3. Fofonoff, N. P., S. P. Hayer and R. C. Millard, 1974. WHOI/Brown CTD Microprofile: Method of calibration and data handling.In: Woods Hole Oceanographic Institute Tech. Rep. WHOI-74-89. Woods Hole MA, USA 64 pp.Google Scholar
  4. Giles, A. B. and T. J. McDougall, 1986. Two methods for the reduction of salinity spiking of CTDs.Deep-Sea Res. 33 (9): 1253–1274.CrossRefGoogle Scholar
  5. Gregg, M. C., J. G. Schedvin, W. G. Hess and T. B. Meagher, 1982. Dynamic response calibration of the Neil Brown conductivity cell.Journal of Physical Oceanography 12: 720–742.CrossRefGoogle Scholar
  6. Gregg, M. C. and T. B. Meagher, 1980. The dynamic response of glass-rod thermistors.Journal of Geophysical 85: 2779–2786.CrossRefGoogle Scholar
  7. Grose, P. L., 1981. CTD data processing. Center for Environmental Assessment Services, NOAA, Washington DC., U.S.A. 28 pp.Google Scholar
  8. Horne, E. P. W., and J. M. Toole, 1980. Sensor response mismatches and lag correction techniques for temperature salinity profilers.J. Phys. Oc. 10: 1122–1130.CrossRefGoogle Scholar
  9. Pingree, R. D., 1971. Regularly spaced instrumental temperature and salinity structures.Deep-Sea Res. 18: 841–844.Google Scholar
  10. Trump, G. L., 1983. Effects of ships roll on the quality of precision CTD data.Deep-Sea Res. 30 (11a): 1173–1183.CrossRefGoogle Scholar
  11. UNESCO, 1988. The acquisition, calibration and analysis of CTD data. In UNESCO Technical Papers in Marine Science, the United Nations Educational, Scientific and Cultural Organization, Paris 93 ppGoogle Scholar

Copyright information

© Science Press 1991

Authors and Affiliations

  • Zhang Aijun
    • 1
  1. 1.National Marine Data and Information ServiceTianjin

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