Browsing by Author "Duguay, Claude R."

Now showing 1 - 2 of 2
  • Thumbnail Image
    Item
    Errata to “Impact of Spectral Resolution on Quantifying Cyanobacteria in Lakes and Reservoirs: A Machine-Learning Assessment”
    (IEEE, 2023-08) Zolfaghari, Kiana; Pahlevan, Nima; Binding, Caren; Gurlin, Daniela; Simis, Stefan G. H.; Verdú, Antonio Ruiz; Li, Lin; Crawford, Christopher J.; VanderWoude, Andrea; Errera, Reagan; Zastepa, Arthur; Duguay, Claude R.; Earth and Environmental Sciences, School of Science
    In the above article [1], the references in the following paragraph should be corrected as shown below. This excerpt appears in the first column on page 4 of the above article.
  • Thumbnail Image
    Item
    Impact of Spectral Resolution on Quantifying Cyanobacteria in Lakes and Reservoirs: A Machine-Learning Assessment
    (IEEE, 2022-10) Zolfaghari, Kiana; Pahlevan, Nima; Binding, Caren; Gurlin, Daniela; Simis, Stefan G. H.; Ruiz Verdú, Antonio; Li, Lin; Crawford, Christopher J.; VanderWoude, Andrea; Errera, Reagan; Zastepa, Arthur; Duguay, Claude R.; Earth Sciences, School of Science
    Cyanobacterial harmful algal blooms are an increasing threat to coastal and inland waters. These blooms can be detected using optical radiometers due to the presence of phycocyanin (PC) pigments. The spectral resolution of best-available multispectral sensors limits their ability to diagnostically detect PC in the presence of other photosynthetic pigments. To assess the role of spectral resolution in the determination of PC, a large ( N=905 ) database of colocated in situ radiometric spectra and PC are employed. We first examine the performance of selected widely used machine-learning (ML) models against that of benchmark algorithms for hyperspectral remote sensing reflectance ( Rrs ) spectra resampled to the spectral configuration of the Hyperspectral Imager for the Coastal Ocean (HICO) with a full-width at half-maximum (FWHM) of < 6 nm. Results show that the multilayer perceptron (MLP) neural network applied to HICO spectral configurations (median errors < 65%) outperforms other ML models. This model is subsequently applied to Rrs spectra resampled to the band configuration of existing satellite instruments and of the one proposed for the next Landsat sensor. These results confirm that employing MLP models to estimate PC from hyperspectral data delivers tangible improvements compared with retrievals from multispectral data and benchmark algorithms (with median errors between ∼73 % and 126%) and shows promise for developing a globally applicable cyanobacteria measurement approach.