Atmospheric Chemistry and Physics Discussions www.atmos-chem-phys-discuss.net 1680-7367 1680-7375 8 2 2008 10.5194/acpd-8-7085-2008 http://www.atmos-chem-phys-discuss.net/8/7085/2008/ http://www.atmos-chem-phys-discuss.net/8/7085/2008/acpd-8-7085-2008.html http://www.atmos-chem-phys-discuss.net/8/7085/2008/acpd-8-7085-2008.pdf 7085 7110 2008-04-10 A computationally-efficient secondary organic aerosol module for three-dimensional air quality models P. Liu Y. Zhang yzhang9@ncsu.edu Dept. of Marine, Earth, and Atmos. Sci., North Carolina State Univ., Raleigh, NC 27519, USA Accurately simulating secondary organic aerosols (SOA) in three-dimensional (3-D) air quality models is challenging due to the complexity of the physics and chemistry involved and the high computational demand required. A computationally-efficient yet accurate SOA module is necessary in 3-D applications for long-term simulations and real-time air quality forecasting. A coupled gas and aerosol box model (i.e., 0-D CMAQ-MADRID 2) is used to optimize relevant processes in order to develop such a SOA module. Solving the partitioning equations for condensable volatile organic compounds (VOCs) and calculating their activity coefficients in the multicomponent mixtures are identified to be the most computationally-expensive processes. The two processes can be speeded up by relaxing the error tolerance levels and reducing the maximum number of iterations of the numerical solver for the partitioning equations for organic species; turning on organic-inorganic interactions only when the water content associated with organic compounds is significant; and parameterizing the calculation of activity coefficients for organic mixtures in the hydrophilic module. The optimal speed-up method can reduce the total CPU cost by up to a factor of 29.7 with ±15% deviation from benchmark results. These speedup methods are applicable to other SOA modules that are based on partitioning theories. Andersson-Sköld, Y. and Simpson, D.: Secondary organic aerosol formation in northern Europe: a model study, J. Geophys. Res., 106(D7), 7357–7374, 2001. Ansari, A. S. and Pandis, S. N.: Water absorption by secondary organic aerosol and its effect on inorganic aerosol behavior, Environ. Sci. Technol., 34, 71–77, 2000. Aumont, B., Madronich, S., Bey, I., and Tyndall, G. S.: Contribution of secondary VOC to the composition of aqueous atmospheric particles: a modeling approach, J. Atmos. Chem., 35, 59–75, 2000. Barthelmie, R. J. and Pryor, S. C.: A model mechanism to describe oxidation of monoterpenes leading to secondary organic aerosol 1. $\alpha $-pinene and $\beta $-pinene, J. Geophys. Res., 104(D19), 23 657–23 670, 1999. Binkowski, F. S. and Roselle, S. J.: Models-3 Community Multiscale Air Quality (CMAQ) model aerosol component 1. Model description, J. Geophys. Res., 108 (D6), 4183, doi:10.1029/2001JD001409, 2003. Choi, M. Y. and Chan, C. K.: The effects of organic species on the hygroscopic behaviors of inorganic aerosols, Environ. Sci. Technol., 36, 2422–2428, 2003. Clegg, S. L., Seinfeld, J. H., and Brimblecombe, P.: Thermodynamic modeling of aqueous aerosols containing electrolytes and dissolved organic compounds, J. Aerosol Sci., 32, 713–738, 2001. Cruz, C. N. and Pandis, S. N.: Deliquescence and hygroscopic growth of mixed inorganic-organic atmospheric aerosol, Environ. Sci. Technol., 34, 4313–4319, 2000. Davidson, C. I., Phalen, R. F., and Solomon, P. A.: Airborne particulate matter and human health: a review, Aerosol Sci. Technol., 39, 737–749, 2005. Finlayson-Pitts, B. J. and Pitts Jr, J. N.: Atmospheric chemistry: Fundamentals and experimental techniques, John Wiley & Sons, Inc., USA, p. 368 and p. 983, 1986. Fredenslund, A., Gmehling, J., and Rasmussen, P.: Vapor–Liquid equilibria using UNIFAC: a group-contribution method, Elsevier Scientific Publishing, New York, 1977. Griffin, R. J., Dabdub, D., Kleeman, M. J., Fraser, M. P., Cass, G. R., and Seinfeld, J. H.: Secondary organic aerosol 3. Urban/regional scale model of size- and composition-resolved aerosols, J. Geophys. Res., 107(D17), 4334, doi:10.1029/2001JD000544, 2002a. Griffin, R. J., Dabdub, D., and Seinfeld, J. H.: Secondary organic aerosol 1. Atmospheric chemical mechanism for production of molecular constituents, J. Geophys. Res., 107(D17), 4332, doi:10.1029/2001JD000541, 2002b. Griffin, R. J., Nguyen, K., Dabdub, D., and Seinfeld, J. H.: A coupled hydrophobic-hydrophilic model for predicting secondary organic aerosol formation, J. Atmos. Chem., 44, 171–190, 2003. Griffin, R. J., Cocker III, D. R., Flagan, R. C., and Seinfeld, J. H.: Organic aerosol formation from the oxidation of biogenic hydrocarbons, J. Geophys. Res., 104(D3), 3555–3567, 1999. Hertel, O., Berkowicz, R., Christensen, J., and Hov, Ø.: Test of two numerical schemes for use in atmospheric transport-chemistry models, Atmos. Environ., 27A, 2591–2611, 1993. Hesstvedt, E., Hov, Ö., and Isaksen, I. S. A.: Quasi-steady-state approximations in air pollution modeling: a comparison of two numerical schemes for oxidant prediction, Int. J. Chem. Kinet., 10, 971–994, 1978. Hu, X.-M. and Zhang, Y.: Implementation and testing of a new aerosol module in WRF/Chem. Proceedings of the 86$^th$ AMS Annual Meeting/the 8$^th$ Conference on atmospheric chemistry, Atlanta, 2006. Huang, H.-C. and Chang, J. S.: On the performance of numerical solvers for a chemistry submodel in three-dimensional air quality models: 1. Box model simulations, J. Geophys. Res., 106(D17), 20 175–20 188, 2001. IPCC: Intergovernmental panel on climate change, Fourth assessment report, Cambrisge University Press, Cambridge, 2007. Jacobson, M. Z. and Turco, R. P.: SMVGEAR: A sparse-matrix, vectorized Gear code for atmospheric models, Atmos. Environ., 28, 273–284, 1994. Marlow, W. H.: Aerosol microphysics, I: particle interaction, Springer-Verlag, New York, 1980. Nenes, A., Pandis, S. N., and Pilinis, C.: Continued development and testing of a new thermodynamic aerosol module for urban and regional air quality models, Atmos. Environ., 33, 1553–1560, 1999. Odum, J. R., Jungkamp, T. P. W., Griffin, R. J., Forstner, H. J. L., Flagan, R. C., and Seinfeld, J. H.: Aromatics, reformulated gasoline, and atmospheric organic aerosol formation, Environ. Sci. Technol., 31, 1890–1897, 1997. Pankow, J. F.: An absorption model of the gas/aerosol partitioning involved in the formation of secondary organic aerosol, Atmos. Environ, 28, 189–193, 1994. Pun, B., Karamchandani, P., Vijayaraghavan, K., Chen, S.-Y., and Seigneur, C.: Models-3/Community Multiscale Air Quality Model (CMAQ) user's guide to alternative modules: Model of Aerosol Dynamics, Reaction, Ionization, and Dissolution (MADRID), Mercury (Hg), and Advanced Plume Treatment (APT), Electric Power Research Institute, Palo Alto, California, CP194-05-1, 2005. Pun, B. K., Griffin, R. J., Seigneur, C., and Seinfeld, J. H.: Secondary organic aerosol, 2. Thermodynamic model for gas/particle partitioning of molecular constituents, J. Geophys. Res., 107(D17), 4333, doi:10.1029/2001JD000542, 2002. Pun, B. K., Wu, S.-Y., Seigneur, C., Seinfeld, J. H., Griffin, R. J., and Pandis, S. N.: Uncertainties in modeling secondary organic aerosols: Three-dimensional modeling studies in Nashville/Western Tennessee, Environ. Sci. Technol., 37, 3647–3661, 2003. Press, W. H., Teukolsky, S. A., Vetterling, W. T., and Flannery, B. P.: Numerical recipes in C: the art of scientific computing, Cambridge University Press, New York, 1997. Sandu, A., Verwer, J. G., Loon, M. V., Carmichael, G. R., Potra, F. A., Dabdub, D., and Seinfeld, J. H.: Benchmarking stiff ODE solvers for atmospheric chemistry problems-I. Implicit vs explicit, Atmos. Environ., 31, 3151–3166, 1997a. Sandu, A., Verwer, J. G., Blom, J. G., Spee, E. J., Carmichael, G. R., and Potra, F. A.: Benchmarking stiff ODE solvers for atmospheric chemistry problems-II. Rosenbrock solvers, Atmos. Environ., 31, 3459–3472, 1997b. Saxena, P. and Hildemann, L.: Water-soluble organics in atmospheric particles: a critical review of the literature and application of thermodynamics to identify candidate compounds, J. Atmos. Chem., 24, 57–109, 1996. Saxena, P. and Hildemann, L. M.: Water absorption by organics: survey of laboratory evidence and evaluation of UNIFAC for estimating water activity, Environ. Sci. Technol., 31, 3318–3324, 1997. Saxena, P., HildemannL, L. ., McMurry, P. H., and Seinfeld, J. H.: Organics alter hygroscopic behavior of atmospheric particles, J. Geophys. Res., 100(D9), 18 755–18 770, 1995. Schell, B., Ackermann, I. J., Hass, H., Binkowski, F. S., and Ebel, A.: Modeling the formation of secondary organic aerosol within a comprehensive air quality model system, J. Geophys. Res., 106(D22), 28 275–28 294, 2001. Seinfeld, J. H. and Pandis, S. N.: Atmospheric Chemistry and Physics: From Air Pollution to Climate Change, John Wiley & Sons, Inc., New York, 1998. Stokes, R. H. and Robinson, R. A.: Interactions in aqueous nonelectrolyte solutions. I. Solute-solvent equilibria, J. Phys. Chem., 70, 2126–2131, 1966. Strader, R., Lurmann, F., and Pandis, S. N.: Evaluation of secondary organic aerosol formation in winter, Atmos. Environ., 33, 4849–4863, 1999. Tulet, P., Grini, A., Griffin, R. J., and Petitcol, S.: ORILAM-SOA: A computationally efficient model for predicting secondary organic aerosols in three-dimensional atmospheric models, J. Geophys. Res., 111, D23208, doi:10.1029/2006JD007152, 2006. Turpin, B. J., Saxena, P., and Andrews, E.: Measuring and simulating particulate organics in the atmosphere: problems and prospects, Atmos. Environ., 34, 2983–3013, 2000. Watson, J. G.: Visibility: science and regulation, J. Air Waste Manage., 52, 628–713, 2002. US Environmental Protection Agency: CHEM_SOLVER_NOTES. CMAQ release notes, Research Triangle Park, NC, 2004. Zhang, Q, Jimenez, J. L., Canagaratna, M. R., Allan, J. D., Coe, H., Ulbrich, I., Alfarra, M. R., Takami, A., Middlebrook, A. M., Sun, Y. L., Dzepina, K., Dunlea, E., Docherty, K., DeCarlo, P. F., Salcedo, D., Onasch, T., Jayne, J. T., Miyoshi, T., Shimono, A., Hatakeyama, S., Takegawa, N., Kondo, Y., Schneider, J., Drewnick, F., Borrmann, S., Weimer, S., Demerjian, K., Williams, P., Bower, K., Bahreini, R., Cottrell, L., Griffin, R. J., Rautiainen, J., Sun, J. Y., Zhang, Y. M., and Worsnop, D. R.: Ubiquity and dominance of oxygenated species in organic aerosols in anthropogenically-influenced Northern Hemisphere midlatitude, Geophy. Res. Lett., 34, L13801, doi:10.1029/2007GL029979, 2007. Zhang, Y., Bischof, C. H., Easter, R. C., and Wu, P.-T.: Sensitivity analysis of a mixed-phase chemical mechanism using automatic differentiation, J. Geophys. Res., 103(D15), 18 593–18 980, 1998. Zhang, Y., Hu, X.-M., Howell, G. W., Sills, E., Fast, J. D., Gustafson Jr., W. I., Zaveri, R. A., Grell, G. A., Peckham, S. E., and McKeen, S. A.: Modeling atmospheric aerosols in WRF/CHEM, Proceeding of the 2005 Joint WRF/MM5 User's Workshop, Boulder, 27–30 June, 2005. Zhang, Y., Pun, B. K., Vijayaraghavan, K., Wu, S.-Y., Seigneur, C., Pandis, S. N., Jacobson, M., Nenes, A., and Seinfeld, J. H.: Development and application of the Model of Aerosol Dynamics, Reaction, Ionization, and Dissolution (MADRID), J. Geophys. Res., 109, D01202, doi:10.1029/2003JD003501, 2004.