Size-fractionated major and minor particle composition and concentration 
   U.S. GEOTRACES Arctic Cruise (GN01) in 2015 
  PI: Phoebe J. Lam (UC Santa Cruz) 
  Version date: 01-April-2020 
  NOTE: nd = missing data identifier ('no data'; sample lost or not collected);  
        NaN = not a number (failed pump with no volume filtered, so concentration undetermined)