NOAA PMEL Station Chemistry Data

Except for Barrow, submicron samples are collected on a daily basis and Supermicron samples are collected on a weekly basis. At Barrow sample periods change with season and aerosol loading. The submicron - supermicron split is made with a Berner-type cascade impactor having a D50,aero of 1.0 um at the RH of the sample stream. Hence, the submicron data is for particle sizes < 1.0 um and the supermicron data is for particle sizes > 1.0 um and < 10 um. The RH of the sampled aerosol is < 40% at all stations. All samples have been analyzed by ion chromatography for Cl-, NO3-, SO4-2, Na+, NH4+, K+, Mg2+, and Ca+2. Recently, the analysis of MSA-, Br-, and oxalate has been added to some stations. Samples also are analyzed for total mass by gravimetric analysis at 55 +/- 5% RH. All ion and mass concentrations are given as ug/m3 at STP. More details of the sampling and analysis methods can be found in Quinn et al., J. Geophys. Res., 105, 6785 - 6805, 2000. There are two separate files of data for each station: one for submicron data and one for supermicron data.