Tropospheric aerosol microphysics simulation with assimilated meteorology: model description and intermodel comparison

We implement the TwO-Moment Aerosol Sectional (TOMAS) microphysics module into GEOS-CHEM, a CTM driven by assimilated meteorology. TOMAS has 30 size sections covering 0.01–10 μm diameter with conservation equations for both aerosol mass and number. The implementation enables GEOS-CHEM to simulate aerosol microphysics, size distributions, mass and number concentrations. The model system is developed for sulfate and sea-salt aerosols, a year-long simulation has been performed, and results are compared to observations. Additionally model intercomparison was carried out involving global models with sectional microphysics: GISS GCM-II' and GLOMAP. Comparison with marine boundary layer observations of CN10 and CCN(0.2%) shows that all models perform well with average errors of 30–50%. However, all models underpredict CN10 by up to 42% between 15° S and 45° S while overpredicting CN10 up to 52% between 45° N and 60° N, which could be due to the sea-salt emission parameterization and the assumed size distribution of primary sulfate emission, in each case respectively. Model intercomparison at the surface shows that GISS GCM-II' and GLOMAP, each compared against GEOS-CHEM, both predict 40% higher CN10 and predict 20% and 30% higher CCN(0.2%) on average, respectively. Major discrepancies are due to different emission inventories and transport. Budget comparison shows GEOS-CHEM predicts the lowest global CCN(0.2%) due to microphysical growth being a factor of 2 lower than other models because of lower SO 2 availability. These findings stress the need for accurate meteorological inputs, updated emission inventories, and realistic clouds and oxidant fields when evaluating global aerosol microphysics models.

[1]  John H. Seinfeld,et al.  Formation and cycling of aerosols in the global troposphere , 2000 .

[2]  A. Clarke,et al.  An ultrafine sea-salt flux from breaking waves: Implications for cloud condensation nuclei in the remote marine atmosphere , 2006 .

[3]  L. Pirjola,et al.  Parameterizations for sulfuric acid/water nucleation rates , 1998 .

[4]  John H. Seinfeld,et al.  Predicting global aerosol size distributions in general circulation models , 2002 .

[5]  R. Turco,et al.  Modeling coagulation among particles of different composition and size , 1994 .

[6]  U. Lohmann,et al.  Sensitivity of sulphate aerosol size distributions and CCN concentrations over North America to SO x emissions and H2O2 concentrations , 2000 .

[7]  M. Jacobson.  Development and application of a new air pollution modeling system—II. Aerosol module structure and design , 1997 .

[8]  Shian‐Jiann Lin,et al.  Multidimensional Flux-Form Semi-Lagrangian Transport Schemes , 1996 .

[9]  B. Albrecht.  Aerosols, Cloud Microphysics, and Fractional Cloudiness , 1989, Science.

[10]  P. Woodward,et al.  The Piecewise Parabolic Method (PPM) for Gas Dynamical Simulations , 1984 .

[11]  Young-Joon Kim,et al.  An overview of ACE‐Asia: Strategies for quantifying the relationships between Asian aerosols and their climatic impacts , 2003 .

[12]  S. Gong,et al.  A parameterization of sea‐salt aerosol source function for sub‐ and super‐micron particles , 2003 .

[13]  Leiming Zhang,et al.  A size-segregated particle dry deposition scheme for an atmospheric aerosol module , 2001 .

[14]  U. Lohmann,et al.  The sulfate-CCN-cloud albedo effect: a sensitivity study with two general circulation models , 1996 .

[15]  M. Chin,et al.  Tropospheric sulfur simulation and sulfate direct radiative forcing in the Goddard Institute for Space Studies general circulation model , 1999 .

[16]  A. Clarke,et al.  The Pacific marine aerosol: Evidence for natural acid sulfates , 1987 .

[17]  S. Twomey.  Pollution and the Planetary Albedo , 1974 .

[18]  P. Adams,et al.  Global evaluation of CCN formation by direct emission of sea salt and growth of ultrafine sea salt , 2006 .

[19]  K. Carslaw,et al.  Evaluation of a global aerosol microphysics model against size-resolved particle statistics in the marine atmosphere , 2007 .

[20]  J. Coakley,et al.  Climate Forcing by Anthropogenic Aerosols , 1992, Science.

[21]  P. Woodward,et al.  Application of the Piecewise Parabolic Method (PPM) to meteorological modeling , 1990 .

[22]  G. Mann,et al.  A global off-line model of size-resolved aerosol microphysics: II. Identification of key uncertainties , 2005 .

[23]  D. Jacob,et al.  Global modeling of tropospheric chemistry with assimilated meteorology : Model description and evaluation , 2001 .

[24]  M. Chin,et al.  Vertical distributions of sulfur species simulated by large scale atmospheric models in COSAM: Comparison with observations , 2001 .

[25]  O. Edenhofer,et al.  Mitigation from a cross-sectoral perspective , 2007 .

[26]  Axel Lauer,et al.  © Author(s) 2006. This work is licensed under a Creative Commons License. Atmospheric Chemistry and Physics Analysis and quantification of the diversities of aerosol life cycles , 2022 .

[27]  J. W. Fitzgerald,et al.  Marine aerosols: A review , 1991 .

[28]  M. Wesely.  Parameterization of surface resistances to gaseous dry deposition in regional-scale numerical models , 1989 .

[29]  Glenn E. Shaw,et al.  Indian Ocean Experiment: An integrated analysis of the climate forcing and effects of the great Indo-Asian haze , 2001 .

[30]  O. Boucher,et al.  The aerosol-climate model ECHAM5-HAM , 2004 .

[31]  Zong-ci Zhao,et al.  Climate change 2001, the scientific basis, chap. 8: model evaluation. Contribution of Working Group I to the Third Assessment Report of the Intergovernmental Panel on Climate Change IPCC , 2001 .

[32]  Barry J. Huebert,et al.  International Global Atmospheric Chemistry (IGAC) Project's First Aerosol Characterization Experiment (ACE 1): Overview , 1998 .

[33]  Martyn P. Chipperfield,et al.  Evaluation and intercomparison of global atmospheric transport models using 222Rn and other short-lived tracers , 1997 .

[34]  M. Chipperfield,et al.  A tropospheric chemical‐transport model: Development and validation of the model transport schemes , 1999 .

[35]  M. Chin,et al.  Natural and transboundary pollution influences on sulfate‐nitrate‐ammonium aerosols in the United States: Implications for policy , 2004 .

[36]  J. Wilson,et al.  A modeling study of global mixed aerosol fields , 2001 .

[37]  R. Dingenen,et al.  Size distribution and chemical composition of marine aerosols: a compilation and review , 2000 .

[38]  J. Lelieveld,et al.  Simulation of global sulfate distribution and the influence on effective cloud drop radii with a coupled photochemistry sulfur cycle model , 1998 .

[39]  J. Wilson,et al.  Emission-Induced Nonlinearities in the Global Aerosol System: Results from the ECHAM5-HAM Aerosol-Climate Model , 2006 .

[40]  Frank McGovern,et al.  The 2nd Aerosol Characterization Experiment (ACE-2): general overview and main results , 2000 .

[41]  Alfred Wiedensohler,et al.  Regional physical and chemical properties of the marine boundary layer aerosol across the Atlantic during Aerosols99: An overview , 2001 .

[42]  G. Feingold,et al.  An Efficient Numerical Solution to the Stochastic Collection Equation , 1987 .

[43]  William L. Chameides,et al.  Rainout lifetimes of highly soluble aerosols and gases as inferred from simulations with a general circulation model , 1986 .

[44]  D. Jacob,et al.  Sulfate Formation in Sea-Salt Aerosols: Constraints from Oxygen Isotopes , 2005 .

[45]  D. W. Johnson,et al.  The Measurement and Parameterization of Effective Radius of Droplets in Warm Stratocumulus Clouds , 1994 .

[46]  P. J. Rasch,et al.  Radiative forcing due to sulfate aerosols from simulations with the National Center for Atmospheric Research Community Climate Model, Version 3 , 2000 .

[47]  M. Andreae,et al.  Biogenic sulfur emissions and aerosols over the tropical South Atlantic: 3. Atmospheric dimethylsulfide, aerosols and cloud condensation nuclei , 1995 .

[48]  M. Chin,et al.  Analysis of regional budgets of sulfur species modeled for the COSAM exercise , 2001 .

[49]  John C. Gille,et al.  Transport and Chemical Evolution over the Pacific (TRACE-P) aircraft mission: Design, execution, and first results , 2003 .

[50]  J. Hales,et al.  Statistical aspects of the washout of polydisperse aerosols , 1976 .

[51]  M. Jacobson.  Numerical Techniques to Solve Condensational and Dissolutional Growth Equations When Growth is Coupled to Reversible Reactions , 1997 .

[52]  C. Land,et al.  A comparison of large-scale atmospheric sulphate aerosol models (COSAM): overview and highlights , 2001 .

[53]  Xindi Bian,et al.  MIRAGE: Model description and evaluation of aerosols and trace gases , 2004 .

[54]  M. Chin,et al.  Vertical distributions of sulfur species simulated by large scale atmospheric models in COSAM: Comparison with observations: Atmospheric models in COSAM , 2001 .

[55]  Global simulation of tropospheric O3-NOx-hydrocarbon chemistry: 1. Model formulation , 1998 .

[56]  P. Adams,et al.  Efficiency of cloud condensation nuclei formation from ultrafine particles , 2006 .

[57]  J. Seinfeld,et al.  Dynamics of Tropospheric Aerosols , 1995 .

[58]  Richard B. Rood,et al.  Three-dimensional radon 222 calculations using assimilated meteorological data and a convective mixing algorithm , 1996 .

[59]  A. Jaecker-Voirol,et al.  Heteromolecular nucleation in the sulfuric acid-water system , 1989 .

[60]  D. E. Spiel,et al.  A Model of Marine Aerosol Generation Via Whitecaps and Wave Disruption , 1986 .

[61]  J. Lerner,et al.  Use of on-line tracers as a diagnostic tool in general circulation model development 1. Horizontal and vertical transport in the troposphere , 1996 .

[62]  G. Mann,et al.  The contribution of boundary layer nucleation events to total particle concentrations on regional and global scales , 2006 .

[63]  D. Weisenstein,et al.  A dynamic aerosol module for global chemical transport models: Model description , 2004 .

[64]  James G. Hudson,et al.  Evaluation of aerosol direct radiative forcing in MIRAGE , 2001 .

[65]  Olivier Boucher,et al.  The sulfate‐CCN‐cloud albedo effect , 1995 .

[66]  S. Twomey.  The Influence of Pollution on the Shortwave Albedo of Clouds , 1977 .

[67]  B. Stevens,et al.  Elements of the microphysical structure of numerically simulated nonprecipitating stratocumulus , 1996 .

[68]  D. L. Roberts,et al.  A climate model study of indirect radiative forcing by anthropogenic sulphate aerosols , 1994, Nature.

[69]  P. Quinn,et al.  Physical properties of marine boundary layer aerosol particles of the mid-Pacific in relation to sources and meteorological transport , 1996 .

[70]  Anthony S. Wexler,et al.  Modelling urban and regional aerosols—I. model development , 1994 .

[71]  M. Chin,et al.  Analysis of regional budgets of sulfur species modeled for the COSAM exercise: Sulfur species modeled for the COSAM exercise , 2001 .

[72]  J. Seinfeld,et al.  Disproportionate impact of particulate emissions on global cloud condensation nuclei concentrations , 2003 .

[73]  W. C. Graustein,et al.  Vertical transport of tropospheric aerosols as indicated by 7Be and 210Pb in a chemical tracer model , 1996 .

[74]  Zev Levin,et al.  The Evolution of Raindrop Spectra. Part II: Collisional Collection/Breakup and Evaporation in a Rainshaft , 1989 .

[75]  Vincent R. Gray.  Climate Change 2007: The Physical Science Basis Summary for Policymakers , 2007 .

[76]  Martyn P. Chipperfield,et al.  A global off-line model of size-resolved aerosol microphysics: I. Model development and prediction of aerosol properties , 2005 .

[77]  D. Jacob,et al.  A simulation of the Transpacific Transport of Mineral Dust from Asia During Spring 2001: Evaluation of Results from GEOS-CHEM with Ground-based, Aircraft and Satellite Measurements , 2004 .

[78]  D. Jacob,et al.  Constraints from 210Pb and 7Be on wet deposition and transport in a global three‐dimensional chemical tracer model driven by assimilated meteorological fields , 2001 .