A semi-continuous organic carbon-elemental carbon analyzer (Sunset Labs) will be deployed to measure aerosol organic carbon (OC) and elemental carbon (EC). The OCEC Analyzer will be operated on a 45-minute sampling cycle, which will provide a 30-min sample of aerosol OC and EC every 45 min, producing 32 OC and EC measurements per day. A PM2.5 cyclone will be used to sample particles smaller than 2.5 µm. A parallel plate carbon denuder will be placed upstream of the analyzer to minimize any artifacts from the adsorption of organic vapors to the sample filter. Nominal detection limits for the analyzer are ~0.4 µg-C m-3 OC and ~0.1 µg-C m-3 EC.