The Use of Spatial Statistics in Hydrography
Abstract
This paper describes ongoing efforts by the Canadian Hydrographic Service to devise geostatistical techniques for optimizing the nominal line spacing used on bathymetric surveys. This survey planning parameter has a great impact on both the cost of a survey and the confidence that a mariner can have in the resulting chart. Current methodology establishes initial line spacing quite subjectively. The main advantage of the geostatistical method being implemented is that it can estimate both depths and an estimate of their variance for all points within the survey area, regardless of whether they lie on or between sounding profiles. The geostatistical software under development (called "Hydrostat") evaluates the roughness of local bathymetry using available data. It then computes and displays the additional sounding coverage required to map the area to any desired level of confidence. The ideal line spacing for each small zone within the survey area is computed after specifying a maximum allowable standard deviation for interpolated depths lying between the sounding profiles. Developing algorithms for estimating the standard deviation of interpolated depths and ground truthing their accuracy forms the bulk of the work being done. While conceptually identical to the age old rules of thumb used to select and examine shoals, the geostatistical routines being developed can lead to more objective data quality standards and a more efficient deployment of survey resources.Downloads
Published
How to Cite
Issue
Section
License
Copyright
Any permission needed to incorporate material published elsewhere is the responsibility of the authors and it will be assumed that such permission has been maintained.
Authors should also bear the following points in mind:
- The title should be concise and reflect the subject matter
- Long passages of text should be avoided by the appropriate use of sub-titles
- References, which should include only publications cited, should be referenced in the text, thus (Smith, 1988), and be listed alphabetically in the Reference section conforming to the Harvard style. Some typical examples follow:
(i) References from Journals:
Anders, F.J. and Byrnes, M.R.(1991). “Accuracy of shoreline change rates as determined from maps and aerial photographs”, Shore and Beach, 59, pp. 17-26.
(ii) References from Books:
Foley, J.D., van Dam, A., Feiner, S. K. and Hughes, J.F. (1990), Computer Graphics – Principles and Practice, 2nd ed., Addison-Wesley, Reading, MA.
(iii) References from the technical material or research literature:
Smith, A. (1988). Colour photomapping. Report NRC-01-512. National Research Centre. Ottawa, Canada.
(iv) References from a web site:
desJardins, M. (2005). How to succeed in postgraduate study, Applied Ecology Research Group, University of Canberra, viewed 26 April 2009, http://aerg.canberra.edu.au/jardins.t.htm.
Please note that articles will be returned to Authors who do not conform to the IHR referencing policy.
Certain articles, especially those dealing with historical aspects, may well have to quote unpublished, archival or 'cumbersome' material, some of which may require further explanation in note form. In such cases referred material can be cited using numbered superscripts in the text and the list of references thus replaced by a section headed 'Notes' in which explanation of the superscripts is given. Material which has been consulted but not specifically referred to in the text can be included in a separate 'Bibliography'.
Please note that references will not be checked by the Editor and the responsibility for the accuracy rests solely with the author(s).
