Prioritizing ocean colour channels by neural network input reflectance perturbation
Abstract:The radiative transfer model Hydrolight was used to produce 18?000 artificial reflectance spectra representing case 1 and case 2 water conditions. Remote sensing reflectances were generated at the MERIS wavebands 412, 442, 490, 510, 560, 620, 665 and 682?nm from randomly generated triplet combinations of chlorophyll a, non-chlorophyllous particles and coloured dissolved organic matter concentrations. These spectra were used to train multilayer perceptron neural network algorithms to perform the inversion from input reflectances to these three optically active substances. A method is proposed that establishes the neural network output error sensitivity towards changes in the individual input reflectance channels. From the output error produced for each reflectance change, a hypothesis about the importance of each band can be made. Results suggest a strong weight associated to the 620?nm band for the estimation of all three substances.
Document Type: Research Article
Affiliations: Sequoia Scientific, Inc, Westpark Technical Center, 15317 NE 90th Street, Redmond, WA 98052, USA
Publication date: March 1, 2005