Estimation of the spectral diffuse attenuation coefficient of downwelling irradiance in inland and coastal waters from hyperspectral remote sensing data: Validation with experimental data

Simon, Arthi; Shanmugam, Palanisamy

doi:10.1016/j.jag.2016.02.003

Cited by 25 publications

(18 citation statements)

References 28 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In clear waters, K d shows low attenuation coefficient values in blue and green wavelengths and increases exponentially in red and NIR spectral regions because of the increasing absorption of pure water at these wavelengths. 67,68 Generally, underwater habitats cannot be detected by wavelengths past 680 nm due to the great attenuation of pure water. 39 In our turbid coastal waters, the attenuation is high both in NIR and blue spectral regions because of the absorption of water and elevated levels of dissolved and particulate matters in the water column, respectively.…”

Section: Discussionmentioning

confidence: 99%

How much benthic information can be retrieved with hyperspectral sensor from the optically complex coastal waters?

Vahtmäe

Paavel

Kutser

2020

J. Appl. Rem. Sens.

View full text Add to dashboard Cite

The Baltic Sea represents an optically complex case 2 water type, where high concentrations of water column constituents limit acquisition of benthic information. Different preprocessing steps were applied to the hyperspectral compact airborne spectrographic imager (CASI) image to extract as much useful benthic information as possible. Atmospheric correction, minimum noise fraction transform, and sun-glint correction were performed to acquire water surface reflectance data. Additionally, a water column removal procedure was applied to acquire bottom reflectance data. Although retrieved CASI water surface reflectance spectra generally matched the magnitudes and shapes of in situ measured spectra, then the applied water column correction algorithm did not yield accurate bottom reflectance spectra. Therefore, both benthic habitat and bathymetry maps were retrieved from the CASI sea surface image data set. An image-based supervised classification method produced a good quality benthic habitat map from the shallow Pakri study area (depth < 3.0 m) with an overall accuracy of 80%. A site-specific algorithm was developed for the bathymetry retrieval utilizing a green-yellow CASI band ratio. Validation of the bathymetry map for depths shallower than 4.0 m revealed an R 2 value of 0.88 and a root-mean-square error of 0.32 m. The assessment of the benthic substrate detectability limits in the Baltic Sea revealed that, at the wavelength of deepest light penetration (near 570 nm), the depth restriction for CASI benthic substrate detection was 7.6 m for sand, 5.0 m for green macroalgae, 3.0 m for higher order vegetation, and 3.1 m for brown macroalgae. The depth limit to which bathymetric mapping is practical in our study site was estimated to be around 3.5 to 4.0 m. © The Authors. Published by SPIE under a Creative Commons Attribution 4.0 Unported License. Distribution or reproduction of this work in whole or in part requires full attribution of the original publication, including its DOI.

show abstract

Section: Discussionmentioning

confidence: 99%

How much benthic information can be retrieved with hyperspectral sensor from the optically complex coastal waters?

Vahtmäe

Paavel

Kutser

2020

J. Appl. Rem. Sens.

View full text Add to dashboard Cite

show abstract

“…Subsequent study of inland turbid bodies of water found that they strongly attenuate light (Kirk, 1981). More recently, heavy attenuation in turbid bodies of water has been determined by remote sensing of large bodies of water and also from direct measurements of highly attenuating estuarine habitats (Lawrenz et al, 2010;Simon and Shanmugam, 2016). Downwelling irradiance in desert ephemeral pools has not been assessed to date (Scholnick, 1994;Williams, 2005).…”

Section: Introductionmentioning

confidence: 99%

Multiple spectral channels in branchiopods. II. Role in light-dependent behavior and natural light environments

Lessios

Rutowski

Cohen

2018

Journal of Experimental Biology

View full text Add to dashboard Cite

Light is a primary environmental factor used by aquatic invertebrates for depth selection behavior. Many branchiopod crustaceans live in ephemeral aquatic habitats. All branchiopod crustaceans studied to date express four or more visual opsins in their compound eyes. We asked whether two branchiopods, and, use multiple spectral channels to regulate their position in the water column. At the lowest intensities that elicited photonegative behavior, both species had broad spectral bandwidths, suggesting they use multiple spectral photoreceptor classes. Male were more likely to maintain a vertical position 8.0-12.0 cm below the surface than females, independently of whether females were present. Male photopositive behavior at low intensity was restricted to a narrow bandwidth centered at 532 nm, suggesting a single photoreceptor class is used to maintain position above females. We compared ephemeral pools from two regions in Arizona and found that diffuse light attenuation coefficients were two orders of magnitude greater than the most heavily attenuating coastal waters. At less than 1 m of depth, pools were often dimmer than terrestrial habitats under starlight. Soil particle size distribution in each region affected spectral light environments, and behavioral responses of field-caught shrimp were adapted to the spectral properties of their region. The results suggest that branchiopods predominantly use luminance vision summed from multiple spectral photoreceptor classes for depth selection in dim, spectrally variable environments. The neuroanatomical basis for summation is described in a companion paper.

show abstract

“…Particularly, spectral unmixing is a significant step of HSI data processing [3,4], and it correlates closely with realistic applications including land cover mapping [5], mine exploration [6], precision agriculture [7] and marine monitoring [8] and so on. The phenomenon of spectral mixture mainly results from limited spatial resolutions of imaging spectrometer (<30 m) and homogeneous mixture of distinct materials, and it refers to that the observed spectral reflectance at each pixel is physically a spectral mixture of several pure materials or called endmembers [9,10].…”

Section: Introductionmentioning

confidence: 89%

“…Careful initialization of variable B is proven to promote the convergence speeds of Equation (8). In this paper, we implement the two-stage algorithm [48] to initialize the endmember set M (0) and estimate the initial coefficient matrices A (0) and B (0) .…”

Section: The Solution Of Pwaa-emd Modelmentioning

confidence: 99%

See 1 more Smart Citation

A Probabilistic Weighted Archetypal Analysis Method with Earth Mover’s Distance for Endmember Extraction from Hyperspectral Imagery

Sun

Zhang

et al. 2017

Remote Sensing

View full text Add to dashboard Cite

Abstract:A Probabilistic Weighted Archetypal Analysis method with Earth Mover's Distance (PWAA-EMD) is proposed to extract endmembers from hyperspectral imagery (HSI). The PWAA-EMD first utilizes the EMD dissimilarity matrix to weight the coefficient matrix in the regular Archetypal Analysis (AA). The EMD metric considers manifold structures of spectral signatures in the HSI data and could better quantify the dissimilarity features among pairwise pixels. Second, the PWAA-EMD adopts the Bayesian framework and formulates the improved AA into a probabilistic inference problem by maximizing a joint posterior density. Third, the optimization problem is solved by the iterative multiplicative update scheme, with a careful initialization from the two-stage algorithm and the proper endmembers are finally obtained. The synthetic and real Cuprite Hyperspectral datasets are utilized to verify the performance of PWAA-EMD and five popular methods are implemented to make comparisons. The results show that PWAA-EMD surpasses all the five methods in the average results of spectral angle distance (SAD) and root-mean-square-error (RMSE). Especially, the PWAA-EMD obtains more accurate estimation than AA in almost all the classes of endmembers including two similar ones. Therefore, the PWAA-EMD could be an alternative choice for endmember extraction on the hyperspectral data.

show abstract

Estimation of the spectral diffuse attenuation coefficient of downwelling irradiance in inland and coastal waters from hyperspectral remote sensing data: Validation with experimental data

Cited by 25 publications

References 28 publications

How much benthic information can be retrieved with hyperspectral sensor from the optically complex coastal waters?

How much benthic information can be retrieved with hyperspectral sensor from the optically complex coastal waters?

Multiple spectral channels in branchiopods. II. Role in light-dependent behavior and natural light environments

A Probabilistic Weighted Archetypal Analysis Method with Earth Mover’s Distance for Endmember Extraction from Hyperspectral Imagery

Contact Info

Product

Resources

About