Laboratory and Field Studies of Secondary Aerosol Formation and Aging Using a Flow Reactor

EPA Grant Number: F13B10165
Title: Laboratory and Field Studies of Secondary Aerosol Formation and Aging Using a Flow Reactor
Investigators: Palm, Brett Brian
Institution: University of Colorado at Boulder
EPA Project Officer: Lee, Sonja
Project Period: August 1, 2014 through August 1, 2016
Project Amount: $84,000
RFA: STAR Graduate Fellowships (2013) RFA Text |  Recipients Lists
Research Category: Academic Fellowships , Fellowship - Atmospheric Chemistry

Objective:

The sources, formation and aging of secondary organic aerosol (SOA) in the atmosphere are not well constrained, yet this information is critical for regional and global models. This research aims to evaluate the current knowledge of SOA sources (biogenic and anthropogenic) and to quantify the amount and chemistry of SOA formation as a function of oxidant exposure.

Approach:

Ambient air at several internationally collaborative field campaigns will be oxidized in the Potential Aerosol Mass (PAM) oxidation flow reactor and analyzed using a broad suite of gas- and particle-phase instrumentation. In a mass closure experiment, the amount of SOA formed from oxidation of ambient air will be compared to the amount of SOA predicted using laboratory-derived aerosol yields of the known aerosol precursor gases measured in the ambient air. Also, the chemical properties of SOA (e.g., atomic O:C ratio) will be investigated as a function of oxidant exposure.

Expected Results:

The measurements of real-time SOA formation in the flow reactor provide a bridge between the information obtained from the various particlephase and gas-phase measurements that take place at collaborative field campaigns. This abundance of information will be leveraged to explain or identify gaps in knowledge about which gases form SOA and in what yields. By comparing SOA formation from ambient air with and without anthropogenic influence, this research will shed light on how human activity is influencing the chemistry of the atmosphere.

Potential to Further Environmental/Human Health Protection

The ability of models to predict future climate and the impact on air quality of aerosols depends critically on the ability to set parameters for the underlying chemistry of SOA formation, as well as spatial knowledge of SOA sources. This research aims to provide better constraints to these models, so that policy experts can use them to design well-informed, effective climate change mitigation strategies.

Supplemental Keywords:

field campaign, organic aerosol, oxidation flow reactor

Progress and Final Reports:

  • 2015
  • Final