Hyperspectral analysis tools for the multiparameter inversion of water quality factors in coastal regions

Abstract

A major modeling effort has been undertaken to develop and refine tools for extracting water quality parameters from remotely-sensed hyperspectral imagery. An outgrowth of this work is HydroMod, a new tool for calculating radiance distributions using realistic environmental conditions for studies involving remote sensing of water quality. HydroMod mates two established premier codes, MODTRAN and HYDROLIGHT. The idea is to simulate the water-leaving spectral. radiance above and below the surface for varying inputs of water quality parameters. Spectral measurements can then be compared with this family of model predicted water-leaving spectral radiance vectors to find a best match and subsequently the associated water quality parameters that were used to generate the matching curve. The scope of the modeling analysis has been limited to the water-leaving radiance in the vicinity of the surface instead of the radiance reaching the sensor. Once the modeling technique using HydroMod has been refined, the atmospheric correction problem over water can be addressed with greater probability of success and fewer sources of uncertainty. This paper will describe the preliminary results from the model-based approach applied to AVIRIS data of a littoral zone and plans for future refinements in the modeling physics.

Retrieval of color producing agents in Case 2 waters using Landsat 8

“…The retrieval process described in this work was first introduced by Concha & Schott (2014b) and Concha (2015) and is based on previous work done by Raqueño et al (2000), , Pahlevan et al (2012) and Gerace et al (2013). A flow diagram of the process is illustrated in Figure 2.…”

“…At this point the R rs spectra of water pixels in the scene with unknown CPAs concentrations are compared with a LUT of R rs spectra with known CPA concentrations. This comparison is made by using a spectrum-matching technique (Raqueño et al, 2000;Mobley et al, 2005) that calculates the root mean squared error (RMSE) to find the closest match in the LUT. The end products are maps of CPAs concentrations (see Figure 2).…”

“…This C a was determined in lab by a spectrophotometric method as well. For the chlorophyll-a scattering properties, the same massspecific scattering coefficient data used in Raqueño et al (2000) and Raqueño (2003) were utilized.…”

“…The SM mass-specific absorption coefficients are shown in Figure 8.(e). The SM mass-specific scattering coefficients are the same used by Raqueño et al (2000) and Raqueño (2003) for the same area of study and are shown in Figure 8.(f). An FF phase function with backscatter fraction 0.010 was selected as the scattering phase function for the SM.…”

Megacollect 2004: hyperspectral collection experiment over the waters of the Rochester Embayment

“…2 Figure 1 shows an overview of the AVIRIS flight lines and images collected in 1999. These bays and ponds are of particular interest because they represent a diverse and easily accessible set of compartmented aquatic systems that have a varied range of chlorophyll, suspended sediment, and gelbstoff (yellowing organics or colored dissolved organic matter -CDOM) concentrations.…”