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A new algorithm for estimating chlorophyll-a concentration from multi-spectral satellite data in case 2 waters: a simulation based on a controlled laboratory experiment / Y. Oyoma in International Journal of Remote Sensing IJRS, vol 28 n°7-8 (April 2007)  

Public [article]  inInternational Journal of Remote Sensing IJRS > vol 28 n°7-8 (April 2007) . - pp 1437 - 1753 Titre : A new algorithm for estimating chlorophyll-a concentration from multi-spectral satellite data in case 2 waters: a simulation based on a controlled laboratory experiment Type de document : Article/Communication Auteurs : Y. Oyoma, Auteur ; B. Matsushita, Auteur Année de publication : 2007 Article en page(s) : pp 1437 - 1753 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique [Termes IGN] chlorophylle [Termes IGN] image multibande [Termes IGN] Japon [Termes IGN] lac [Termes IGN] matière organique [Termes IGN] plancton Résumé : (Auteur) This paper presents the spectral decomposition algorithm (SDA), a new algorithm for estimating chlorophyll-a concentration in case II waters using multi-spectral satellite data, which is based on a simulation in a controlled laboratory experiment. The SDA is composed of two key steps. The first of these is to consider the mixed reflectance spectrum of a given pixel as a linear combination of three basic components: clear water, non phytoplankton suspended sediments (NPSS), and phytoplankton. The second step is to use a decomposition coefficient (Cp) obtained from the first step as an independent variable in the chlorophyll-a estimation model, instead of the single band reflectance, band ratio or arithmetic calculation of bands used in conventional methods. The simulated results for the Landsat TM data showed that bands 1, 3 and 4 are useful wavelengths for estimating chlorophyll-a concentrations. In the case of a water body with chlorophyll-a concentrations ranging from 0 to 105 ug1-1 and NPSS concentrations ranging from 0 to l00m g1-1, the RMSE of the estimation model of chlorophyll-a concentrations based on the SDA was 13.7 ug1-1, reduced by nearly half of that for conventional methods (the RMSE was 25.6 ug1-for the band ratio, and 25.5 ug1-for the arithmetic calculation of bands). The results of a two-factor ANOVA (without replication) highlight that the decomposition coefficient Cp contains information from phytoplankton far more than from NPSS. However, Cp values were still changed with the addition of NPSS, due mainly to the influence of the interaction of optical properties among phytoplankton, NPSS and water, which occurred in both horizontal and vertical directions in the water bodies. Considering the basic components as a nonlinear combination in a water area may reduce the effect of NPSS on Cp values from that of their linear combination. In addition, the influence of coloured dissolved organic matter (CDOM), which is generally considered as one of the optically active substances in case II waters, was ignored according to the practical conditions of our study area, Lake Kasumigaura, Japan in this paper. Users can set the basic components (or endmembers) freely according to the conditions of their own study area when the SDA is used (e.g. considering the CDOM as a basic component in the SDA). Copyright Taylor & Francis Numéro de notice : A2007-175 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/01431160600975295 En ligne : https://doi.org/10.1080/01431160600975295 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=28538 [article]

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080-07041	RAB	Revue	Centre de documentation	En réserve L003	Disponible

Atmospheric correction algorithm for MERIS above case-2 waters / Th. Schroeder in International Journal of Remote Sensing IJRS, vol 28 n°7-8 (April 2007)  

Public [article]  inInternational Journal of Remote Sensing IJRS > vol 28 n°7-8 (April 2007) . - pp 1469 - 1486 Titre : Atmospheric correction algorithm for MERIS above case-2 waters Type de document : Article/Communication Auteurs : Th. Schroeder, Auteur ; I. Behnert, Auteur ; et al., Auteur Année de publication : 2007 Article en page(s) : pp 1469 - 1486 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image [Termes IGN] aérosol [Termes IGN] classification par réseau neuronal [Termes IGN] correction atmosphérique [Termes IGN] image Envisat-MERIS [Termes IGN] modèle de transfert radiatif [Termes IGN] réflectance Résumé : (Auteur) The development and validation of an atmospheric correction algorithm designed for the Medium Resolution Imaging Spectrometer (MERIS) with special emphasis on case-2 waters is described. The algorithm is based on inverse modelling of radiative transfer (RT) calculations using artificial neural network (ANN) techniques. The presented correction scheme is implemented as a direct inversion of spectral top-of-atmosphere (TOA) radiances into spectral remote sensing reflectances at the bottom-of-atmosphere (BOA), with additional output of the aerosol optical thickness (AOT) at four wavelengths for validation purposes. The inversion algorithm was applied to 13 MERIS Level 1b data tracks of 2002-2003, covering the optically complex waters of the North and Baltic Sea region. A validation of the retrieved AOTs was performed with coincident in situ automatic sun-sky scanning radiometer measurements of the Aerosol Robotic Network (AERONET) from Helgoland Island located in the German Bight. The accuracy of the derived reflectances was validated with concurrent ship-borne reflectance measurements of the SIMBADA hand-held field radiometer. Compared to the MERIS Level2 standard reflectance product generated by the processor versions 3.55, 4.06 and 6.3, the results of the proposed algorithm show a significant improvement in accuracy, especially in the blue part of the spectrum, where the MERIS Level 2 reflectances result in errors up to 122% compared to only 19% with the proposed algorithm. The overall mean errors within the spectral range of 412.5-708.75 nm are calculated to be 46.2% and 18.9% for the MERIS Level2 product and the presented algorithm, respectively. Copyright Taylor & Francis Numéro de notice : A2007-176 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/01431160600962574 En ligne : https://doi.org/10.1080/01431160600962574 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=28539 [article]

Exemplaires(1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
080-07041	RAB	Revue	Centre de documentation	En réserve L003	Disponible

Mapping land cover from detailed aerial photography data using textural and neural network analysis / R. Cots-Folch in International Journal of Remote Sensing IJRS, vol 28 n°7-8 (April 2007)  

Public [article]  inInternational Journal of Remote Sensing IJRS > vol 28 n°7-8 (April 2007) . - pp 1625 - 1642 Titre : Mapping land cover from detailed aerial photography data using textural and neural network analysis Type de document : Article/Communication Auteurs : R. Cots-Folch, Auteur ; M.J. Aitkenhead, Auteur ; et al., Auteur Année de publication : 2007 Article en page(s) : pp 1625 - 1642 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image [Termes IGN] analyse texturale [Termes IGN] carte d'occupation du sol [Termes IGN] classification par réseau neuronal [Termes IGN] image aérienne [Termes IGN] paysage agricole [Termes IGN] photographie panchromatique [Termes IGN] utilisation du sol Résumé : (Auteur) Automated mapping of land cover using black and white aerial photographs, as an alternative method to traditional photo-interpretation, requires using methods other than spectral analysis classification. To this end, textural measurements have been shown to be useful indicators of land cover. In this work, a neural network model is proposed and tested to map historical land use/land cover (LUC) from very detailed panchromatic aerial photographs (5m resolution) using textural measurements. The method is used to identify different land use and management types (e.g. traditional versus mechanized vineyard systems). These have been tested with known ground reference data. The results show the potential of the methodology to obtain automatic, historic, and very detailed cartography information from a complex landscape such as the mountainous and Mediterranean region to which it is applied here, and the advantages that this method has over traditional methods. Copyright Taylor & Francis Numéro de notice : A2007-177 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/01431160600887722 En ligne : https://doi.org/10.1080/01431160600887722 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=28540 [article]

Exemplaires(1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
080-07041	RAB	Revue	Centre de documentation	En réserve L003	Disponible