A Semi-Analytical Model for Remote Sensing Retrieval of Suspended Sediment Concentration in the Gulf of Bohai, China

Abstract

Suspended sediment concentration (SSC) is one of the most critical parameters in ocean ecological environment evaluation and it can be determined using ocean color remote sensing (RS). The purpose of this study is to develop a model that provides a reliable and sensitive evaluation of SSC retrieval using RS data. Data were acquired for and gathered from the Gulf of Bohai where SSC levels are relatively low with an average value below 30 mg·L −1. The study indicates that the most sensitive band to SSC levels in the study area is the NIR band of Landsat5 TM images. A quadratic polynomial semi-analytical model appears to be the best retrieval model based on the relationship between the inherent optical properties (IOPs) and apparent optical properties (AOPs) of water as described by the quasi-analytical algorithm (QAA). The model has a higher precision and effectiveness for SSC retrieval than data-driven statistical models, especially when SSC level is relatively high. The average relative error and the root mean square error (RMSE) are 12.32% and , respectively, while the correlation coefficient between observed and estimated SSC by the model is 0.95. Using the proposed retrieval model and TM data, SSC levels of the entire study region in the Gulf of Bohai were estimated. These estimates can serve as the baseline for efficient monitoring of the ocean environment in the future.

A Semi-Analytic Model for Estimating Total Suspended Sediment Concentration in Turbid Coastal Waters of Northern Western Australia Using MODIS-Aqua 250 m Data

“…For the case of the NIR region (>750 nm) there is no clear difference among Rrs spectra for TSS less than 13 mg/L, but for higher TSS there is a distinct increment in magnitude of Rrs with the NIR Rrs exhibiting an increasingly more distinct peak at ~810 nm. The selection of the red band and NIR bands for SASM are in agreement with [61] in considering band's responsiveness to TSS concentration in establishing a good retrieval model. In our spectral data, the reflectance at the red and NIR bands responds well with TSS concentration, as shown by the distinct increase in the magnitude of red band reflectance with increase in TSS concentration for all TSS concentrations, while the NIR band shows distinct increments for TSS concentrations greater than 13 mg/L.…”

“…The poor performance result for rrs(B2) may be because most of the available TSS measurements in our data set were lower. At low TSS concentrations and in the NIR wavelengths where the reflectance measurements are relatively low, results may be better modelled with a simple linear model which works well in low TSS The selection of the red band and NIR bands for SASM are in agreement with [61] in considering band's responsiveness to TSS concentration in establishing a good retrieval model. In our spectral data, the reflectance at the red and NIR bands responds well with TSS concentration, as shown by the distinct increase in the magnitude of red band reflectance with increase in TSS concentration for all TSS concentrations, while the NIR band shows distinct increments for TSS concentrations greater than 13 mg/L.…”

“…Semi-analytic TSS algorithms include model parameters that use in situ regional IOPs [54], averaged IOPs representative of wider geographical locations [60] or IOPs inverted from site specific satellite reflectance [61]. The site specific IOPs used in parameterizing these models are potentially the best for retrieving site-specific TSS.…”

Application of the Geostationary Ocean Color Imager to Mapping the Diurnal and Seasonal Variability of Surface Suspended Matter in a Macro-Tidal Estuary

“…Advances have been made in numerous studies in the development of algorithms for suspended solids after the introduction of ocean colour sensors, such as Gordon's semi-analytical algorithm, logarithm algorithm, power exponential algorithm and synthetic algorithm [35][36][37][38][39].…”

Preface: Remote Sensing of Water Resources

“…Kong et al [3] developed a semi-analytical model based on quasi analytical algorithm (QAA) to retrieve suspended sediment concentrations (SSC) for the Gulf of Bohai, China. Model comparisons revealed a higher accuracy and universality for the developed model.…”