The use of NOAA AVHRR satellite data for mapping sediment variability in the marine and coastal environment
Sediment-rich effluent from the Atchafalaya River (USA) flows into the clear waters of the Gulf of Mexico along the Louisiana Coast. The sediment, which serves as a material for shoreline progradation, is transported by near shore currents to various portions of the coastal zone. Satellite data from the National Oceanographic and Atmospheric Administration's (NOAA) Advanced Very High Resolution Radiometer (AVHRR), 1.1km resolution, atmospherically corrected channel 1 and 2, are used to map the suspended sediment transport in the Atchafalaya Bay region of the Louisiana coastal zone. The turbid water equation was solved with the Newton method of non-linear curve fitting using the suspended sediment concentration obtained from the field sample analysis and the satellite-derived Reflectance values for Rw. The values of the constants Fs and Gs are 0.66 and 32.86, respectively, with R2 = 0.8895 and the root mean square error for reflectance is 0.0089. Results based on four satellite images show that the suspended sediment plume transported along the shore, to the west is 10km wide on the average when southeast winds dominate. However, the suspended sediment transported to the deep sea in response to the passage of winter cold fronts could reach as far out to the sea as 70km when the northeast winds dominate. The area near Big Constance Lake, which has a persistently higher concentration of suspended sediment around the year, is a suspected non-depositional area. The southwest winds cause a circulation in the bay and thus periods of higher depositional rates.
Journal of Building and Land Development Vol. 13 (2) 2006: pp. 65-73