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Armin Aulinger, Volker Matthias, and Markus Quante

conditions The boundary conditions for the inner domain were derived from simulation results of the outer domain, whereas the boundary conditions of the large grid were set to be near zero. We currently have no exact cognition about the boundary conditions of the outer domain. At the same time, the most significant PAH and particle sources are situated south and east of the model domain while the predominant wind direction is west. Tests showed that boundary conditions for the outer domain do not

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Edith Gégo, P. Steven Porter, Alice Gilliland, and S. Trivikrama Rao

of the Acid Rain Program on ozone are considerably less than those of the SIP Call (4% reduction resulting from the Acid Rain Program vs 10% resulting from the SIP Call), our results represent the effect of all emission changes that have occurred from 1997 to 2004, not those solely due to the implementation of the SIP Call. Because meteorological conditions greatly affect ozone formation and accumulation, it is important to moderate their influence on ozone concentrations prior to assessing the

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Ho-Chun Huang, Xin-Zhong Liang, Kenneth E. Kunkel, Michael Caughey, and Allen Williams

FDDA is not ideal. The only possible input data for the FDDA technique is from climate “projections” of a general circulation model (GCM), the use of which would incorporate all of the regional climate biases of the GCM into the MMM simulation. Most RCMs are driven by lateral boundary conditions (LBCs) at their domain edges for the entire period ( Liang et al. 2001 ; Bouchet et al. 1999a , b ). These LBCs are provided either by global reanalysis data for validation/evaluation purposes or by GCM

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John S. Irwin, William B. Petersen, and Steven C. Howard

1. Introduction Implicit in current air quality models, and in the discussion of this paper, is the assumption that the temporal and spatial variations in observed hourly concentration values can be envisioned as being partly deterministic and partly stochastic. For specified boundary conditions, the deterministic part of the concentration variations in time and space are the ensemble-average hourly concentrations to be seen at each location in the modeling domain. What we observe at any given

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M. Talat Odman, Yongtao Hu, Alper Unal, Armistead G. Russell, and James W. Boylan

2018-OTW includes the clean air interstate rule. It was assumed that any potential feedback of future land use and emissions on the meteorology would be negligible. Therefore meteorological inputs developed for the July 2001 and January 2002 periods were also used for the 2018 simulations. Biogenic emissions were also assumed to remain constant in the future. Initial and boundary conditions were derived from a 36-km resolution simulation of 2018 over North America. A two-day ramp-up period was used

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Jesse O. Bash, Patricia Bresnahan, and David R. Miller

emission modeling work Several natural mercury emissions models have been developed recently for use with AQMs. A summary of recent natural emissions modeling efforts is presented in Table 1 . In these models, natural mercury emissions from vegetation, soil, and surface waters are modeled as lower boundary conditions for the San Joaquin Valley Air Quality Study and Atmospheric Utility Signatures, Prediction, and Experiments Regional Modeling Adaptation Project (SARMAP) Air Quality Model (SAQM) and

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George Kallos, Marina Astitha, Petros Katsafados, and Chris Spyrou

. Impacts of synoptic/regional circulation patterns on transport and transformation processes of PM are discussed thoroughly in this work. b. Regional climatological description The Mediterranean Sea is closed from all sides and is surrounded by high peninsulas and important mountain barriers. The gaps between these major mountainous regions act as channels for the airmass transport toward the GMR. The climatic conditions in the GMR can be roughly divided into cold and warm periods ( Maheras et al. 1999

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Golam Sarwar and Prakash V. Bhave

using the Meteorology–Chemistry Interface Program, version 2.3. The predefined clean air vertical profiles for initial and boundary concentrations provided in the CMAQ modeling system were used in this study. The model was spun up for 7 days to minimize the effect of initial conditions on model predictions. Two model simulations were performed with the following two mechanisms for July 2001: 1) the Carbon Bond (CB05) mechanism, and 2) the combined CB05 and chlorine mechanism. The CB05 mechanism

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