Development of a Geo-spatial Analysis Methodology for Assessing the Adequacy of Hydrographic Surveys and Nautical Charts
IHO Publication C-55 (Status of Hydrographic Surveying and Nautical Charting Worldwide) contains information about the progress of hydrographic surveying and nautical charting for a country with navigable waters under its jurisdiction. Listed primarily as percent coverage, it is difficult to use this information to determine: 1) if the current level of surveying or charting is adequate or in need of action, or 2) can be used to compare different locations. An analysis and assessment methodology has been developed to assess the adequacy of hydrographic surveying and nautical charting coverage. Indications of chart adequacy and completeness as depicted on current charts or sailing directions are spatially correlated with significant maritime sites/areas associated with social, environmental and economic factors. Areas within the charts were prioritized low, medium and high priority areas for survey. However, analysis based solely on these datasets is limited to data available at the time of last survey. Publically-available, multi-spectral satellite imagery and published algorithms can be used to derive estimates of the relative bathymetry in shallow, clear waters. The potential of this method was evaluated in terms of supplementing the priority procedure in assessing the adequacy hydrographic surveying and nautical charting coverage. Preliminary results show that multi-spectral satellite remote sensing can be a beneficial reconnaissance tool prior to conducting a hydrographic acoustic survey and for marine spatial planning. Both procedures were developed in a GIS environment for Belize and Nigeria.
Chukwuma Azuike is a hydrographer with the Nigerian Hydrographic Office. A 2000 graduate of the Nigerian Defense Academy, he has served in a variety of naval positions in the Nigerian Navy. In 2010, he began a MS Degree program at the Center for Coastal and Ocean Mapping at the University of New Hampshire.