Development of a low-cost bathymetric mapping system for tsunami inundation modeling | |
| Author | Layug, J. Elaine J. |
| Call Number | AIT Thesis no.RS-10-07 |
| Subject(s) | Bathymetric maps Tsunamis--Thailand--Bathymetric maps |
| Note | A thesis submitted in partial fulfilment of the requirements for the degree of Master of Science in Remote Sensing and Geographic Information System |
| Publisher | Asian Institute of Technology |
| Series Statement | Thesis ; no. RS-10-07 |
| Abstract | In light of the recent major disasters in the coastal areas, the need to acquire accurate and timely bathymetric data in shallow waters is vital to coastal and disaster management. Unfortunately, not all areas have complete and accurate bathymetric data. Herein lies the problem, since typical bathymetric surveys are expensive, it is impractical to update bathymetric data every time a disaster strikes, much less acquire sufficient data in developing countries located in the Indo-Pacific region. On the other hand, most nautical charts exist in small scale, the accuracy of which may not be acceptable for tsunami research. There is a need therefore to develop a methodology, inexpensive but accurate enough, to survey and generate bathymetric data for tsunami simulation and inundation modeling. In this study, several techniques to improve the accuracy of the bathymetric DEM have been evaluated. These are the selection of the best interpolation method and optimum boat survey route design, detection of local variation and conducting detailed bathymetric survey in these areas. The reference sonar data used for all accuracy assessment was acquired from the Hydrographic Department of the Royal Thai Navy. This study recommends the combination of the 500 m interval perpendicular to the shoreline with 100 m detailed interval parallel to the shoreline for the boat survey route. In addition, the Natural Neighbor interpolation method, which gave the least RMSE for all bathymetric conditions, should be used to generate the bathymetric DEM. More importantly, results show that the addition of detailed survey to the DEM without detailed survey has improved its accuracy by 73%. Cost also plays an important role in selection of the optimum methodology. Higher accuracy demands higher cost. But if the survey route is designed effectively, such as the addition of the detailed bathymetric survey in local variation areas, the accuracy can be normalized for all the routes and hence, selection of the best survey route design will be reduced to selection of the lowest cost. Results show that the recommended route has attained comparable accuracy with the reference sonar data but with a 70% reduction in survey cost. This proves that the methodology is effective in generating high accuracy but inexpensive bathymetric data for tsunami simulation and inundation modeling. |
| Year | 2010 |
| Corresponding Series Added Entry | Asian Institute of Technology. Thesis ; no. RS-10-07 |
| Type | Thesis |
| School | School of Engineering and Technology |
| Department | Department of Information and Communications Technologies (DICT) |
| Academic Program/FoS | Remote Sensing (RS) |
| Chairperson(s) | Honda, Kiyoshi |
| Examination Committee(s) | Souris, Marc;Sutat Weesakul |
| Scholarship Donor(s) | AIT Fellowship |
| Degree | Thesis (M.Sc.) - Asian Institute of Technology, 2010 |