The use of multi‐temporal satellite images to estimate intertidal reef‐flat topography

Extracting waterlines under various water‐level conditions can provide topographic information on intertidal areas, because the waterlines can be regarded as contours. This waterline method was applied to two platform reefs in Australia. Waterlines extracted by Terra ASTER band 3 indicated emerged parts of the reef flats (a palaeo reef flat, cemented rubble/ pavement, and a high prominent ridge) successfully. Comparisons between positions of waterlines extracted and topographic profiles by Kench and Brander (2006) showed the horizontal errors of the positions were similar to those estimated previously. The results suggest the general applicability of the waterline method to coral reef environments.

Keywords:

• Intertidal reef flat topography
• Terra ASTER
• Warraber Island
• Lady Elliot Island