Grantee Research Project Results
Anthropogenic Secondary Organic Particulate Matter: From Measurements to Models to MitigationEPA Grant Number: FP917186
Title: Anthropogenic Secondary Organic Particulate Matter: From Measurements to Models to Mitigation
Investigators: Hildebrandt, Lea
Institution: Carnegie Mellon University
EPA Project Officer: Lee, Sonja
Project Period: August 23, 2010 through August 22, 2013
Project Amount: $111,000
RFA: STAR Graduate Fellowships (2010) RFA Text | Recipients Lists
Research Category: Academic Fellowships , Fellowship - Clean Air
Submicron atmospheric particles are of interest because they adversely affect human health and regional visibility, and they have a highly uncertain effect on climate. Organic aerosol (OA) globally comprises 20-90% of the submicron particle mass, but a full understanding of its formation, evolution, and characteristics remains elusive. The goal of this research project is to better understand the processes governing the properties and concentrations of OA, facilitating the articulation of policy actions that lead to a reduction in atmospheric OA and its adverse effects.
Fine atmospheric particles adversely affect human health, and they have a highly uncertain effect on climate. OA globally comprises 20-90% of the fine particle mass, but a full understanding of its formation, evolution and characteristics remains elusive. The goal of this project is to improve air quality by better understanding OA, facilitating the articulation of policy actions that lead to a reduction in OA and its adverse effects on human health and the environment.
The main part of this project focuses on investigating OA through a series of laboratory experiments and ambient measurements. In particular, we measure the potential of individual gaseous precursors to form OA in laboratory experiments. We also explore the changes in OA (“aging”) in laboratory experiments by further oxidizing the OA after its initial formation. We observe the effects of OA aging in the atmosphere by measuring ambient OA at a remote location that is not influenced by fresh pollution. Finally, we investigate the interactions of different types of OA in the laboratory by forming them during the same experiment. We use isotopic labeling and a high-resolution aerosol mass spectrometer to distinguish between the different OA types.
The experiments and ambient measurements will provide insights into the formation, transformation, and interactions of organic aerosol (OA). Based on these new insights, we will develop improved model parameterizations and include them in the three-dimensional chemical transport model PMCAMx. We will then test the model against observations from ambient measurements. Finally, we will use the improved model to evaluate different emission control options for reducing OA concentrations and then make recommendations for regulatory efforts aimed at mitigating OA concentrations.
Potential to Further Environmental/Human Health Protection:
This project will enable the development of more effective policy actions aimed at reducing organic aerosol and total fine particle concentrations in the atmosphere. This will lead to decreased adverse effects from fine particles on human health and the environment.