Tidal effect is one of the primary factors that causes unwarranted variability in salt marsh reflectance characteristics and introduces errors in remote sensing based biophysical models. Tide induced variability is particularly worse in coarse resolution datasets such as Moderate-resolution Imaging Spectroradiometer (MODIS) 250m data where it is not possible to visually detect the affected pixels or scenes. This study presents a novel index, TAWI (Tide Adjusted Wetland Index) for identifying images with no tide or very low tide using temporally dense MODIS data. Logistics regression based TAWI was used to filter out flooded images from MODIS sensor. Overall phenology derived for 15 years pre- and post-TAWI showed that post-TAWI phenology was able to eliminate the noise due to tide influence. Eliminating flooded data from salt marsh phenology using TAWI will provide accurate remote estimation for numerous biophysical parameters including chlorophyll content, above and below ground biomass, and gross primary productivity.
