Feasibility of Elevation Mapping in Muddy Tidal Flats by Remotely Sensed Moisture (RSM) Method

Li, H.; Gong Z.; Dai, W.Q.; Lu, C.Z.; Zhang, X.Y; Cybele, S., and Guo, H.T., 2018. Feasibility of elevation mapping in muddy tidal flats by remotely sensed moisture (RSM) method. In: Shim, J.-S.; Chun, I., and Lim, H.S. (eds.), Proceedings from the International Coastal Symposium (ICS) 2018 (Busan, Republic of Korea). Journal of Coastal Research, Special Issue No. 85, pp. 291–295. Coconut Creek (Florida), ISSN 0749-0208. It is hard for traditional ways to measure muddy intertidal topography because of its difficult access and limitation of exposure time. As a result, this paper proposes a new way, called remotely sensed moisture (RSM) method, to retrieve elevation in muddy tidal flats. When the tide ebbs, the intertidal flat exposes gradually from the land to the sea, thus forming a phenomenon of ‘low moisture in high-lying areas and high moisture in low-lying areas’. It can be seen that there may exist the negative correlation between the moisture and elevation of intertidal flat. By means of TM Image at low tide, this paper retrieved the moisture of muddy intertidal flat and found out that there does exist the negative correlation, but relatively low (R2=0.55). Further analysis showed that the remnant water is a critical factor to affect the correlation. After excluding regions nearby waterlines, the correlation between moisture and elevation is improved significantly (R2=0.78). The research demonstrates that RSM method has a potential to map topography of muddy tidal flats.