Breakout Summary Report
ARM/ASR User and PI Meeting
13 - 17 March 2017
16 March 2017
10:45 AM - 12:45 PM
30
John Shilling, Joel Thornton, Scot Martin
Breakout Description
The guiding philosophy for cooperative science in the secondary organic aerosol (SOA) focus group, both for incorporating knowledge into models and identifying new and important emerging topics for study, is to focus on process-level details of SOA formation and aging that are missing in global earth system models and have large potential implications on radiative forcing. The goals of the session were to share and discuss the latest results of Atmospheric System Research (ASR)-funded SOA research including laboratory, field, and modeling efforts, and to plan for future collaborative efforts and emphases. We also updated participants on the status of the manuscript submitted to Reviews of Geophysics based on the SOA workshop report discussed at the ASR meeting last year.Main Discussion
The session consisted of two parts: an update from principal investigators on research progress and a discussion of strategies for bridging the gap between process-level measurements and information and models.
In the first part of the session, Alla Zelenyuk, Jose Jimenez, Joel Thornton, Qi Zhang, Markus Petters, Rahul Zaveri, Scot Martin, and John Shilling gave three- to five-slide presentations updating the group on key findings from their research linked with ASR or the Atmospheric Radiation Measurement (ARM) Climate Research Facility. Scot Martin presented new results on the uptake of organic vapors onto SOA as a function of relative humidity. Alla Zelenyuk showed results on the uptake of ammonia by SOA both at low and high relative humidity. Rahul Zaveri presented results on modeling growth kinetics of bi-modal externally mixed SOA and seed particles during competitive growth experiments. Marcus Petters presented a description of work on the SOA phase diagram in terms of viscosity as a function of temperature and relative humidity. Jose Jimenez posed a question of whether gas-particle partitioning can be studied in a chamber, given that vapor wall loss can be important. Qi Zhang showed formation and aging of biomass burning organic aerosol in the context of the Biomass Burning Observation Project (BBOP) campaign. Joel Thornton showed results from the Biogenic Aerosols – Effects on Clouds and Climate (BAECC) campaign and a chamber study (SOA Formation from Forest Emissions Experiment, or SOAFFEE) on the importance of organic nitrates in nighttime oxidation of a-pinene in the presence of nitrogen oxide—a potential anthropogenic enhancement of SOA. John Shilling advertised a special opportunity for proposing to use capabilities of the Environmental Molecular Sciences Laboratory, a U.S. Department of Energy national scientific user facility.
The second part of the discussion revolved around the merits of holding a workshop/meeting to develop a mechanism for incorporating SOA process studies into models. The general concept is to provide a community resource that could be used by individual principal investigators to incorporate process-level details into a model where it could be evaluated for impact. This resource would allow for evaluation of process-level details by non-expert users (e.g., a graduate student with modest programming skills) before those details were fully vetted for inclusion in an earth system model. There was general support for this type of community resource, though there was considerable uncertainty regarding the details of what type of model was necessary (e.g., box, regional) and the exact vision for the resource. A proposal was put forward to organize a meeting in which principal investigators would meet to present intentionally different visions for the resource with the goal of fleshing out the details and coming to a consensus. The group supported the proposal to organize such a meeting, and a small committee of volunteers was organized to prepare a short white paper describing the workshop/meeting proposal. The white paper would be circulated to the SOA group after being drafted by the committee.