Poster Session 3, Wednesday, October 5, 16:00–18:00
Characterizing the physical properties and carbon content of suspended particles along a vulnerable coastline using IOPs retrieved from imaging spectroscopy
The quantification of suspended-particle fluxes in nearshore coastal systems is essential to understanding carbon sequestration and coastline vulnerability. To accurately model these processes, it is critical to quantify particle biogeochemical and physical characteristics that influence the fate of suspended particles. Inherent optical properties (IOPs) can act as proxies for particle concentration and characteristics, facilitating the quantification of these parameters across spatially and temporally heterogeneous coastal systems. In optically complex coastal waters, imaging spectroscopy (hyperspectral imagery) offers significant advantages for distinguishing contributions from different constituents and retrieving IOPs. As part of the NASA Delta-X project, we characterized suspended particle properties at more than 170 stations across contrasting waters in the Mississippi River Delta in Louisiana, USA. These field measurements included remote-sensing reflectance (Rrs), Particulate organic carbon (POC) concentration, particle absorption spectra (ap , aphi , ad), total suspended sediment concentration, grain size distribution (LISST-200X), and backscattering (bb). Using this dataset, we developed relationships between specific IOPs and particle physical and biogeochemical properties. We are also developing a novel semi-analytical algorithm, utilizing remote imaging spectroscopy, that retrieves IOPs in order to infer POC concentration and particle characteristics in complex coastal waters. Applying this algorithm to simultaneously collected high spectral resolution imagery from NASA’s AVIRIS-NG instrument, we will quantify differences in POC and particle characteristics across contrasting basins with stable and eroding coastal marshes. New capabilities for retrieving particle properties are particularly exciting in the context of upcoming imagers (e.g. GLIMR and SBG) that will provide unprecedented hyperspectral imagery of nearshore coastal systems.
Nilotpal Ghosh, Boston University, [email protected]
Matthew Weiser, Boston University, [email protected]
David Thompson, Jet Propulsion Laboratory, California Institute of Technology, [email protected]
Xiaohui Zhu, Boston University, [email protected]
Cédric Fichot, Boston University, [email protected]