Published: 23 July 2013

Organic aerosol (OA, i.e., the organic fraction of particles) accounts for 10–90% of the fine aerosol mass globally and is a key determinant of aerosol radiative forcing. But atmospheric OA is poorly characterized and its life cycle insufficiently represented in models. As a result, current models are unable to simulate OA concentrations and properties. This deficiency represents a large source of uncertainty in the quantification of aerosol direct and indirect effects and the prediction of future climate change.

The Organic Aerosol Component (OACOMP) value-added product (VAP) uses organic mass spectral matrix data collected by the aerosol chemical speciation monitor (ACSM) and multivariate analysis to obtain an estimate of the types of organic aerosols. Currently, time series of biomass burning organic aerosol (BBOA) and two types of secondary organic aerosol (SOA) (less-oxidated organic aerosol, LOOA, and more-oxidized organic aerosol, MOOA) are produced. These data are needed to assess the performance of aerosol models and determine whether the total organic aerosols are being simulated for the right reasons. For the convenience of users, OACOMP also includes the time series of total organic matter, sulfate, nitrate, ammonium, and chloride that is measured by the ACSM.

OACOMP is currently in evaluation mode, and any comments on the data set are welcome. The evaluation data are available for January 2011 through March 2012 from the Southern Great Plains (SGP) site. This VAP will run autonomously when the evaluation is complete. More information is available at the VAP web page.

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