Previously, the best suited satellite sensor available for mapping bathymetry was Landsat 7, however with the advent of high resolution satellite sensors such as Quickbird and IKONOS in the last decade, far more accurate assessments could be made.
Since the launch of the Worldview 2 satellite by Digital Globe, a new era of bathymetric mapping has now commenced. The Worldview 2 satellite as an excellent spectral band conveniently placed between 400 and 450nm called Coastal Blue.
Because of the manner in which blue light is attenuated in water, and with a spatial resolution of 1.8m, has enabled accurate bathymetric measurement to be made to depth of more than 20m.
Below is an example is from Mandurah, Western Australia. Project aim was to not only map bathymetry in the Peel Inlet, but also monitor estuary vegetation types and their extent at various depths.
Worldview2 Bathymetry Mapping
Mandurah Normal Colour
Mandurah Algorithm Enhanced ‘Coastal Blue’
Several key factors still need to be determined before any bathymetric mapping project can commence:
- Targets
- Climate and date/s of imagery to be acquired
- Collection Nadir angle
- Sun angle
- Ground-truthed base points
- Sea condition
- Turbidity
Please don’t hesitate to contact Mr Trevor Marshall if you have further questions regarding using Remote Sensing for bathymetric mapping.
