Size fractionation for total Chl a within the surface layer and calculated size distribution of total Chl a from discrete bottle samples collected during CCE LTER process cruises in the CCE region, 2006 - 2024 (ongoing).

Water for size fractionation of chlorophyll a is sampled from ~10m depth (surface layer) in the CCE study area. The size distribution of total chlorophyll a is determined by filtering water though filters of differing pore sizes. These are then extracted in acetone and analyzed fluorometrically with Turner Designs 10-AU Fluorometer on CCE Process cruises (since 2006, ongoing). Chlorophyll a and taxon-specific pigments (chlorophylls and carotenoids) are qualitatively and quantitatively characterized in the lab onshore by several size fractions (< 1µm to > 20µm) utilizing High Performance Liquid Chromatography (HPLC) analysis. The samples analyzed within the CCE region are used to develop a metric for phytoplankton community structure that can be used to monitor its state and changes thereof over time.