Chapter 59
Evaluation of Seven Chemical Aging
Modeling Schemes with the 2D-VBS
Framework Against Ground
and Airborne PEGASOS Campaign
Measurements
Eleni Karnezi, Benjamin N. Murphy and Spyros N. Pandis
Abstract The 2D-VBS framework describing the organic aerosol (OA) distribution
as a function of its volatility and O:C is used in PMCAMx-Trj, a one–dimensional
Lagrangian chemical transport model. The model is used to simulate the atmospheric
OA during two PEGASOS campaigns in the Po Valley in Italy during 2012 and in
Hyytiälä, Finland during 2013. Po Valley is an area with many industrial and agricultural sources and Hyytiälä is characterized by high biogenic secondary OA (SOA)
levels. The simulations are evaluated with AMS measurements both at the ground
and aloft with a Zeppelin airship. There were seven aging schemes with different
assumptions about functionalization, biogenic SOA aging, and fragmentation that
succeeded in reproducing the AMS measurements within measurement error. For all
seven schemes, the assumed enthalpy of evaporation had a surprisingly small effect
on the diurnal and vertical profiles of O:C and OA concentration. Even if the seven
schemes have relatively different characteristics and assumptions, all provide a rather
similar picture about the different sources and processes contributing to the total OA
in these two very different areas.
E. Karnezi (B) · S. N. Pandis
Department of Chemical Engineering, Carnegie Mellon University,
Pittsburgh, PA 15213, USA
e-mail: ekarnezi@andrew.cmu.edu
S. N. Pandis
e-mail: spyros@chemeng.upatras.gr
B. N. Murphy
National Exposure Research Laboratory, United States Environmental Protection Agency,
Research Triangle Park, Durham, NC 27709, USA
e-mail: ben.n.murphy@gmail.com
S. N. Pandis
Department of Chemical Engineering, University of Patras, 26504 Patra, Greece
© Springer Nature Switzerland AG 2020
C. Mensink et al. (eds.), Air Pollution Modeling and its Application XXVI,
Springer Proceedings in Complexity,
https://doi.org/10.1007/978-3-030-22055-6_59
371
Evaluation of Seven Chemical Aging
Modeling Schemes with the 2D-VBS
Framework Against Ground
and Airborne PEGASOS Campaign
Measurements
Eleni Karnezi, Benjamin N. Murphy and Spyros N. Pandis
Abstract The 2D-VBS framework describing the organic aerosol (OA) distribution
as a function of its volatility and O:C is used in PMCAMx-Trj, a one–dimensional
Lagrangian chemical transport model. The model is used to simulate the atmospheric
OA during two PEGASOS campaigns in the Po Valley in Italy during 2012 and in
Hyytiälä, Finland during 2013. Po Valley is an area with many industrial and agricultural sources and Hyytiälä is characterized by high biogenic secondary OA (SOA)
levels. The simulations are evaluated with AMS measurements both at the ground
and aloft with a Zeppelin airship. There were seven aging schemes with different
assumptions about functionalization, biogenic SOA aging, and fragmentation that
succeeded in reproducing the AMS measurements within measurement error. For all
seven schemes, the assumed enthalpy of evaporation had a surprisingly small effect
on the diurnal and vertical profiles of O:C and OA concentration. Even if the seven
schemes have relatively different characteristics and assumptions, all provide a rather
similar picture about the different sources and processes contributing to the total OA
in these two very different areas.
E. Karnezi (B) · S. N. Pandis
Department of Chemical Engineering, Carnegie Mellon University,
Pittsburgh, PA 15213, USA
e-mail: ekarnezi@andrew.cmu.edu
S. N. Pandis
e-mail: spyros@chemeng.upatras.gr
B. N. Murphy
National Exposure Research Laboratory, United States Environmental Protection Agency,
Research Triangle Park, Durham, NC 27709, USA
e-mail: ben.n.murphy@gmail.com
S. N. Pandis
Department of Chemical Engineering, University of Patras, 26504 Patra, Greece
© Springer Nature Switzerland AG 2020
C. Mensink et al. (eds.), Air Pollution Modeling and its Application XXVI,
Springer Proceedings in Complexity,
https://doi.org/10.1007/978-3-030-22055-6_59
371