Examining CDOM fluorescence variability using principal component analysis: seasonal and regional modeling of three-dimensional fluorescence in the Gulf of Mexico

Alterations in colored dissolved organic matter (CDOM) characteristics were examined for an extensive fluorescence data set generated by excitation emission matrix spectroscopy (EEMS). Principal component analysis (PCA) was used to assess changes in fluorescence bandwidth and wavelength shifts of entire peak regions, enhancing previous CDOM characterization that was based on changes observed at a few excitation and emission wavelength pairs. Variability within the data set is expressed as a series of linear terms, which can be used to quantitatively evaluate changes in CDOM fluorescence within the perspective of a single cruise or a large geographic region. In this paper we will present PCA results from a comprehensive fluorescence data set examining seasonal and regional CDOM variability within the Gulf of Mexico.