World Library  


Add to Book Shelf
Flag as Inappropriate
Email this Book

Modeling Natural Emissions in the Community Multiscale Air Quality (Cmaq) Model – Part 2: Modifications for Simulating Natural Emissions : Volume 10, Issue 6 (28/06/2010)

By Mueller, S. F.

Click here to view

Book Id: WPLBN0003995454
Format Type: PDF Article :
File Size: Pages 74
Reproduction Date: 2015

Title: Modeling Natural Emissions in the Community Multiscale Air Quality (Cmaq) Model – Part 2: Modifications for Simulating Natural Emissions : Volume 10, Issue 6 (28/06/2010)  
Author: Mueller, S. F.
Volume: Vol. 10, Issue 6
Language: English
Subject: Science, Atmospheric, Chemistry
Collections: Periodicals: Journal and Magazine Collection, Copernicus GmbH
Historic
Publication Date:
2010
Publisher: Copernicus Gmbh, Göttingen, Germany
Member Page: Copernicus Publications

Citation

APA MLA Chicago

Mao, Q., Mallard, J. W., & Mueller, S. F. (2010). Modeling Natural Emissions in the Community Multiscale Air Quality (Cmaq) Model – Part 2: Modifications for Simulating Natural Emissions : Volume 10, Issue 6 (28/06/2010). Retrieved from http://worldlibrary.in/


Description
Description: Tennessee Valley Authority, P.O. Box 1010, Muscle Shoals, Alabama 35662-1010, USA. A recent version (4.6) of the Community Multiscale Air Quality (CMAQ) model was used as the basis for testing model revisions for including reactions involving chlorine (HCl, ClNO2) and reduced sulfur (dimethylsulfide, or DMS, and H2S) species not normally treated in the CB05 gas chemical mechanism and cloud chemistry module. Model chemistry revisions were based on published reaction kinetic data and a recent cloud chemistry model that includes heterogeneous reactions of organic sulfur compounds. Testing of the revised model was conducted using a recently enhanced data base of natural emissions that includes ocean and continental sources of DMS, H2S, chlorinated gases and lightning NOx for the continental United States and surrounding regions. Results using 2002 meteorology and emissions indicated that most simulated chemical and aerosol species exhibit the expected seasonal variations in grid-average surface concentrations. Ozone exhibits a winter and early spring maximum – reasonably consistent with ozone data and model results produced by others – in a pattern that reflects the influences of atmospheric dynamics and pollutant background levels imposed on the CMAQ simulation by boundary conditions derived from a global model. A series of experimental model simulations reveals that the addition of gas phase organic sulfur chemistry leads to sulfate aerosol increases over most of the continental United States. Modifications to the cloud chemistry module result in widespread decreases in SO2 across the modeling domain and a mix of sulfate increases and decreases. Most cloud-mediated sulfate increases occurred over the Pacific Ocean (up to about 0.1 μg m-3) and at slightly lesser amounts over and downwind from the Gulf of Mexico (including portions of the Eastern US). Variations in the chemical response are due to the link between DMS/H2S and their byproduct SO2, the heterogeneity of cloud cover and precipitation (precipitating clouds act as net sinks for SO2 and sulfate), and the persistence of cloud cover (the largest relative sulfate increases occurred over the persistently cloudy Gulf of Mexico and western Atlantic Ocean). Overall, the addition of organic sulfur chemistry increased surface hourly sulfate levels by as much as 1–2 μg m-3 in selected grid cells. The added chemistry produced significantly less sulfate in the vicinity of high SO2 emissions (e.g., wildfires), perhaps in response to lower OH from competing reactions with DMS and its derivatives. Simulated surface levels of DMS compare favorably with published observations made in the marine boundary layer. However, DMS derivatives are lower than observed implying either less chemical reactivity in the model or a low bias in the boundary conditions for DMS derivatives such as dimethylsulfoxide. The sensitivity of sulfate to cloud cover and the aqueous sulfate radical is also explored. This revised version of CMAQ provides a tool for more realistically evaluating the influence of natural emissions on air quality.

Summary
Modeling natural emissions in the Community Multiscale Air Quality (CMAQ) model – Part 2: Modifications for simulating natural emissions

Excerpt
Atkinson, R., Baulch, D. L., Cox, R. A., Crowley, J. N., Hampson, R. F., Hynes, R. G., Jenkin, M. E., Rossi, M. J., and Troe, J.: Evaluated kinetic and photochemical data for atmospheric chemistry: Volume I - gas phase reactions of \chem{O_x}, HOx, NOx and \chem{SO_x} species, Atmos. Chem. Phys., 4, 1461–1738, doi:10.5194/acp-4-1461-2004, 2004.; Atkinson, R., Baulch, D. L., Cox, R. A., Crowley, J. N., Hampson, R. F., Hynes, R. G., Jenkin, M. E., Rossi, M. J., Troe, J., and IUPAC Subcommittee: Evaluated kinetic and photochemical data for atmospheric chemistry: Volume II �- gas phase reactions of organic species, Atmos. Chem. Phys., 6, 3625–4055, doi:10.5194/acp-6-3625-2006, 2006.; Atkinson, R., Baulch, D. L., Cox, R. A., Crowley, J. N., Hampson, R. F., Hynes, R. G., Jenkin, M. E., Rossi, M. J., and Troe, J.: Evaluated kinetic and photochemical data for atmospheric chemistry: Volume III – gas phase reactions of inorganic halogens, Atmos. Chem. Phys., 7, 981–1191, doi:10.5194/acp-7-981-2007, 2007.; Ayers, G. P. and Gillett, R. W.: DMS and its oxidation products in the remote marine atmosphere: implications for climate and atmospheric chemistry, J. Sea Res., 43, 275–286, 2000.; Behnke, W., George, C., Scheer, V., and Zetzsch, C.: Production and decay of ClNO2 from the reaction of gaseous N2O5 with NaCl solution: bulk and aerosol experiments, J. Geophys. Res., 102, 3795–3804, 1997.; Berntsen, T. K. and Isaksen, I. S. A.: A global 3-D chemical transport model for the troposphere: model description and CO and O3 results, J. Geophys. Res., 102, 21239–21280, 1997.; Berntsen, T. K., Karlsdóttir, S., and Jaffe, D. A.: Influence of Asian emissions on the composition of air reaching the north western United States, Geophys. Res. Lett., 26, 2171–2174, 1999.; Bonifacic, M., Mockel, H., Bahnemann, D., and Asmus, K. D.: Formation of positive-ions and other primary species in oxidation of sulfides by hydroxyl radicals, J. Chem. Soc. Perk. T., 2(7), 675–685, 1975.; Byers, H. R.: Elements of Cloud Physics, The University of Chicago Press, Chicago, 142–146, 1965.; Hoffman, M. R.: On the kinetics and mechanism of oxidation of aquated sulfur-dioxide by ozone, Atmos. Environ., 20, 1145–1154, 1986.; Chawla, O. P. and Fessenden, R. W.: Electron-spin resonance and pulse-radiolysis studies of some reactions of \chem{SO_{4}^{-}}, J. Phys. Chem., 79, 2693–2700, 1975.; De Valk, J. P. J.M.M. and van der Hage, J. C. H.: A model for cloud chemistry processes suitable for use in long range transport models: a sensitivity study, Atmos. Environ., 28, 1653–1663, 1994.; EPA: Guidance for Tracking Progress under the Regional Haze Rule, Office of Air Quality Planning and Standards, Research Triangle Park, NC, EPA-454/B-03–004, 2003.; EPA: Review of the National Ambient Air Quality Standards for Particulate Matter: Policy Assessment of Scientific and Technical Information, Office of Air Quality Planning and Standards, Research Triangle Park, NC, EPA-452/R-05–005, 2005.; Erickson, D. J. III, Seuzaret, C., Keene, W. C., and Gong, S. L.: A general circulation model based calculation of HCl and ClNO2 production from sea salt dechlorination: reactive chlorine emissions inventory, J. Geophys. Res., 104, 8347–8372, 1999.; Ervens, B., Carlton, A. G., Turpin, B. J., Altieri, K. E., Kreid

 

Click To View

Additional Books


  • Sensitivity of Cloud Condensation Nuclei... (by )
  • Uptake of Hypobromous Acid (Hobr) by Aqu... (by )
  • The Scout-o3 Darwin Aircraft Campaign: R... (by )
  • The Travel-related Carbon Dioxide Emissi... (by )
  • Dependence of Aerosol-precipitation Inte... (by )
  • Reactive Nitrogen Partitioning and Its R... (by )
  • Effects of Relative Humidity on Aerosol ... (by )
  • Frequency of Deep Convective Clouds in t... (by )
  • Envisat Mipas Measurements of Cfc-11: Re... (by )
  • Secondary Organic Material Formed by Met... (by )
  • Influence of Aerosol Acidity on the Chem... (by )
  • Improvement of Climate Predictions and R... (by )
Scroll Left
Scroll Right

 



Copyright © World Library Foundation. All rights reserved. eBooks from World Library are sponsored by the World Library Foundation,
a 501c(4) Member's Support Non-Profit Organization, and is NOT affiliated with any governmental agency or department.