Simulation and analysis of secondary organic aerosol dynamics in the South Coast Air Basin of California
نویسندگان
چکیده
[1] The dynamics of secondary organic aerosol (SOA) formation are analyzed using a species-resolved SOA model for the South Coast Air Basin of California (SoCAB). Updated versions of the Caltech Atmospheric Chemistry Mechanism (CACM) and the Model to Predict the Multiphase Partitioning of Organics (MPMPO) are integrated with the CIT airshed model. The simulations are performed using input data from the 8–9 September 1993 episode. Results show that urban areas with major volatile organic compound (VOC) emission sites experience peaks in SOA levels during morning hours. Downwind locations, such as Azusa and Claremont, experience sustained levels of high SOA concentrations in comparison with coastal areas such as central Los Angeles and Long Beach. Concentrations of condensible organics are higher in inland locations compared to those in coastal locations because of high oxidation capacity and transport of pollutants. Furthermore, SOA constitutes up to 30% of simulated organic particulate matter at inland locations, with maximum contributions occurring during afternoon hours. Anthropogenic sources contribute over 90% of simulated SOA at most locations in the basin. Oxidation products of aromatic compounds from anthropogenic sources constitute over 70% of total simulated SOA. Sensitivity runs indicate strong dependence of SOA on VOC emissions and temperature. Overall, model predictions are in qualitative agreement with recent observations in the SoCAB.
منابع مشابه
Calculations of incremental secondary organic aerosol reactivity.
The incremental secondary organic aerosol reactivity (ISOAR) of a species j is defined as the relative incremental change in secondary organic aerosol (SOA) formed per relative incremental change in the amount of species jemitted. The California Institute of Technology three-dimensional air quality model is used in conjunction with the Caltech Atmospheric Chemistry Mechanism (CACM) and the Mode...
متن کاملSecondary organic aerosol formation from naphthalene roadway emissions in the South Coast Air Basin of California
متن کامل
Secondary organic aerosol 3. Urban/regional scale model of size and compositionresolved aerosols
[1] The California Institute of Technology (CIT) three-dimensional urban/regional atmospheric model is used to perform comprehensive gasand aerosol-phase simulations of the 8 September 1993 smog episode in the South Coast Air Basin of California (SoCAB) using the atmospheric chemical mechanism of part 1 [Griffin et al., 2002] and the thermodynamic module of part 2 [Pun et al., 2002]. This paper...
متن کاملNOx and VOC Control and Its Effects on the Formation of Aerosols
This research analyzes thequalitative and quantitative behavior of aerosol dynamics resulting from the control of nitrogen oxide (NOx) and volatile organic compound (VOC) emissions by calculating detailed pollutant isopleths. Several emission scenarios are evaluated using various norms to study the nonlinear impact of control strategies. The modeling episode studied is the Southern California A...
متن کاملMulti-generational oxidation model to simulate secondary organic aerosol in a 3-D air quality model
Multi-generational gas-phase oxidation of organic vapors can influence the abundance, composition and properties of secondary organic aerosol (SOA). Only recently have SOA models been developed that explicitly represent multigenerational SOA formation. In this work, we integrated the statistical oxidation model (SOM) into SAPRC-11 to simulate the multi-generational oxidation and gas/particle pa...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 2006