Air was continuously pumped at 5 to 10 L/min through a plastic coated aluminum tubing (Dekoron) sample line that ran from the an inlet at the top of the aerosol sampling mast (18 m above sea level, forward of the ship’s bridge) to the analytical system at the forward end of the ship's main oceanographic laboratory. The analytical system was a PMEL built, automated GC system consisting of a mole sieve 5A chromatographic column and a Trace Analytical reduction gas detector. Every seven minutes a 5 ml sample of air from the sample line, air standard from a gas cylinder, or CO free air from a zero air generator was injected into the system. The air standards were dried, whole-air mixtures contained in aluminum cylinders and were calibrated by NOAA/CMDL. The sampling schedule was such that generally 3 air sample were analyzed per hour. The data presented on this server consist of one hour averages of the all CO measurements during that hour. There were several occasions when the ship was running downwind when it was obvious that ship exhaust was entering the air sample line; these data points were removed before averaging. There was a 2 day data gap during day-of-year 101-102 when the uv lamp in the detector was failing. The detector was fixed by the start of DOY 103.
Data can be downloaded in ACF format by following the ASCII link, or in binary netCDF file format by following the netCDF link