The Organic Aerosol Composition (OACOMP) value-added product for the ARM Data Archive
Poster PDF
Authors
Qi Zhang — University of California, Davis
Timothy R. Shippert — Pacific Northwest National Laboratory
Jerome D Fast — Pacific Northwest National Laboratory
Chitra Sivaraman — Pacific Northwest National Laboratory
Fan Mei — Pacific Northwest National Laboratory
Alison Tilp — Brookhaven National Laboratory
Category
Infrastructure & Outreach
Description
Secondary organic aerosols (SOA) comprise a large fraction of the aerosol mass in the atmosphere at many locations; however, the formation of SOA is poorly understood and represented by atmospheric models. This deficiency represents a large source of uncertainty in quantification of aerosol effects on radiation and clouds and consequently the prediction of future climate. Evaluation and development of aerosol process modules require data products generated from field observations. Aerosol mass spectrometers (AMS) have been frequently used in DOE-supported field campaigns for characterizing aerosol composition and elucidating aerosol sources and processes. In addition, three units of Aerosol Chemical Speciation Monitor (ACSM) were recently added to the TWP and SGP long-term measurement sites and mobile aerosol observing system (MAOS). The ACSM is a “mini” version of the AMS developed for continuous, low-maintenance operation. The typical time resolution of AMS measurements is 2–5 minutes at fixed sites and 30 seconds or less on mobile platforms (e.g., aircraft), while the time resolution of ACSM is generally 30 minutes. Code is currently being adapted that takes measurements of total organic matter and other spectra information from the ACSM and derives the primary and secondary fractions of organic matter. The code will be run operationally within ARM’s Data Management Facility, and the new data product, called the Organic Aerosol Composition (OACOMP) value-added product, will eventually be made available on the ARM Data Archive. This presentation will describe the motivation for OACOMP, quality assurance (QA) procedures, how the organic aerosol components are derived, progress that has been made including preliminary results, as well as anticipated operational implementation. Information on the primary and secondary components will be valuable for modelers when evaluating new treatments of organic matter.
