PRINCIPAL 



INVESTIGATOR(S) Julie La Roche 



Oceanographic and Atmospheric Sciences Division 

 Brookhaven National Laboratory 

 Upton, NY 11973 



PROJECT TITLE PARTICULATE INORGANIC CARBON 



AMOUNT OF FUNDING FY 1994: $0 K (BNL Laboratory Directed Research and 



Development (LDRD)) 



SUMMARY OF GOALS 



The goal of this project is to examine the distribution of particulate inorganic carbon 

 (PIC) and its role in the carbon cycle on the continental margin near Cape Hatteras. Effects of 

 PIC on alkalinity and pC0 2 will be studied. Laboratory experiments will be conducted in parallel 

 to identify the environmental factors favorable to calcification in the major calcifying 

 phytoplankter, Emiliania huxleii. The scientific objectives are as follows: 1) Quantify the 

 amount of particulate inorganic carbon (PIC) in the water column over a seasonal cycle. 2) 

 Assess the abundance of calcified and naked coccolithophorids, in particular Emiliania huxleii, 

 the dominant calcifying phytoplankton species in the study region. 3) Conduct laboratory 

 experiments to identify the environmental factors that promote calcification in coccolithophorids. 

 4) Survey images of water-leaving radiance from the coastal zone color scanner (CZCS) to 

 identify potential blooms of coccolithophorids. 



SPATIAL AND TEMPORAL SAMPLING SCALES 



Most of the research can be conducted from ships. Samples can be collected on most of 

 the OMP hydrographic and biological cruises, and either stored for lab analysis or processed at 

 sea. Proper coverage requires cross-shelf transects and seasonal distribution of the cruises, 

 including fall and winter sampling. 



METHODS AND PLATFORMS 



PIC will be measured from filtered seawater samples using a Gas chromatography 

 technique (GC-FID) which has a detection limit for C0 2 of the order of 10-10 moles. The filtered 

 samples will be rinsed, dried, acidified and the C0 2 captured for analysis. Using 0.2 pg of 

 carbon per coccolith and a minimum coccolith concentration of 10 4 1" 1 (non-bloom conditions), 

 there should be a background PIC of 10" 9 moles/1 so that even low PIC could be detected by 



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