title: Statistical analysis of absorption spectra of phytoplankton and of pigment concentrations observed during three POMME cruises using a neural network clustering method.
abstract: We present a neural network methodology for clustering large data sets into pertinent groups. We applied this methodology to analyze the phytoplankton absorption spectra data gathered by the Laboratoire d'Océanographie de Villefranche. We first partitioned the data into 100 classes by means of a self-organizing map (SOM) and then we clustered these classes into 6 significant groups. We focused our analysis on three POMME campaigns. We were able to interpret the absorption spectra of the samples taken in the first oceanic optical layer during these campaigns, in terms of seasonal variability. We showed that spectra from the PROSOPE Mediterranean campaign, which was conducted in a different region, were strongly similar to those of the POMME-3 campaign. This analysis led us to propose regional empirical relationships, linking phytoplankton absorption spectra to pigment concentrations, that perform better than the previously derived overall relation.
authors.affiliation: Laboratoire d'Océanographie et du Climat: Expérimentations et Approches Numériques (LOCEAN/IPSL), Paris, France. ayclod@locean-ipsl.upmc.fr
authors.forename: Aymeric
authors.initials: A
authors.lastname: Chazottes
authors.forename: Michel
authors.initials: M
authors.lastname: Crépon
authors.forename: Annick
authors.initials: A
authors.lastname: Bricaud
authors.forename: Joséphine
authors.initials: J
authors.lastname: Ras
authors.forename: Sylvie
authors.initials: S
authors.lastname: Thiria
mesh_terms: D000465:Algorithms; D016000:Cluster Analysis; D003627:Data Interpretation, Statistical; D015233:Models, Statistical; D016571:Neural Networks, Computer; D010363:Pattern Recognition, Automated; D010839:Phytoplankton / Q000378:metabolism*; D010858:Pigmentation; D012044:Regression Analysis; D015203:Reproducibility of Results; D012621:Seasons; D013053:Spectrophotometry; D014867:Water / Q000737:chemistry
chemical_list: D014867:Water