An extended dry deposition model for aerosols onto broadleaf canopies

Abstract This paper presents a model to predict transport and dry deposition of aerosols in and to a canopy composed of plane leaves such as a grassland, a crop field or a broadleaf forest under conditions of neutral stability. This model is based on an approach detailed by Petroff et al. [2008b. Aerosol dry deposition on vegetative canopies. Part II: A new modeling approach and applications. Atmospheric Environment , 42 , 3654–3683]. Collection parameterizations specific to plane obstacles are derived here for the processes of Brownian diffusion, interception, inertial and turbulent impactions, and gravitational settling. For the process of interception, an original formulation is derived based on the potential flow theory applied to inclined plane surfaces. The validity of the model predictions is evaluated using existing experiments both on the scale of isolated obstacles such as inclined plates and broadleaf twigs, and on the scale of entire canopies of grass, moorland and forest. Under these different configurations, the model agrees reasonably with measurements. Moreover, this comparison emphasizes the strong influence of canopy and aerosol properties on deposition and explains, at least partly, the variability of existing measurement data sets obtained in similar aerodynamic conditions.

[1]  O. Stedman,et al.  DEPOSITION OF AIR‐BORNE LYCOPODIUM SPORES ON PLANE SURFACES , 1953 .

[2]  Rudolf B. Husar,et al.  An eddy-correlation measurement of particulate deposition from the atmosphere☆ , 1977 .

[3]  Dennis D. Baldocchi,et al.  Turbulence structure in a deciduous forest , 1988 .

[4]  Per Ambus,et al.  Field measurements of atmosphere-biosphere interactions in a Danish beech forest , 2003 .

[5]  Ü. Rannik,et al.  Measurements of aerosol particle dry deposition velocity using the relaxed eddy accumulation technique , 2007 .

[6]  Micrometeorological measurements of particle deposition velocities to moorland vegetation , 2002 .

[7]  M. Gallagher,et al.  Measurements of aerosol fluxes to Speulder forest using a micrometeorological technique , 1997 .

[8]  G. Csanady.  Turbulent Diffusion of Heavy Particles in the Atmosphere , 1963 .

[9]  W. Slinn,et al.  Predictions for particle deposition to vegetative canopies , 1982 .

[10]  D. Aylor,et al.  Modeling spore dispersal in a barley crop , 1982 .

[11]  J. R. Starr.  Inertial impaction of particulates upon bodies of simple geometry. , 1967, Annals of Occupational Hygiene.

[12]  Ü. Rannik,et al.  Effects of continental boundary layer evolution, convection, turbulence and entrainment, on aerosol formation , 2001 .

[13]  Christopher W. Fairall,et al.  Interpretation of eddy-correlation measurements of particulate deposition and aerosol flux , 1984 .

[14]  W. S. Clough.  The deposition of particles on moss and grass surfaces , 1975 .

[15]  B. Hicks,et al.  The Forest-Atmosphere Interaction , 1985 .

[16]  W. Massman.  Foliage distribution in old-growth coniferous tree canopies , 1982 .

[17]  H. Blasius.  Grenzschichten in Flüssigkeiten mit kleiner Reibung , 1907 .

[18]  J. Grace.  The turbulent boundary layer over a flapping Populus leaf , 1978 .

[19]  P. Little.  Deposition of 2.75, 5.0 and 8.5 μm particles to plant and soil surfaces , 1977 .

[20]  R. D. Wiffen,et al.  Emission and deposition of petrol engine exhaust Pb--I. Deposition of exhaust Pb to plant and soil surfaces. , 1977, Atmospheric environment.

[21]  A. C. Chamberlain,et al.  Transport of Lycopodium spores and other small particles to rough surfaces , 1967, Proceedings of the Royal Society of London. Series A. Mathematical and Physical Sciences.

[22]  Fabien Anselmet,et al.  Aerosol dry deposition on vegetative canopies. Part II: A new modelling approach and applications , 2008 .

[23]  R. E. Lawson,et al.  A “test of concept” comparison of aerodynamic and mechanical resuspension mechanisms for particles deposited on field rye grass (Secale cercele). Part 1. Relative particle flux rates , 2004 .

[24]  D. M. Gates,et al.  Wind-tunnel modelling of convection of heat between air and broad leaves of plants , 1968 .

[25]  U. KyawThaPaw,et al.  Experimental Evidence of the Importance of Rebound in Net Deposition of Particles , 1992 .

[26]  G. Langer.  Particle deposition on and reentrainment from coniferous trees , 1965 .

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

[28]  S. Larsen,et al.  Upward fluxes of particles over forests: when, where, why? , 2008 .

[29]  U. KyawThaPaw.  The rebound of particles from natural surfaces , 1983 .

[30]  R. Barthelmie,et al.  A review of measurement and modelling results of particle atmosphere–surface exchange , 2008 .

[31]  K. R. May,et al.  The Impaction of Aerosol Particles on Cylinders, Spheres, Ribbons and Discs , 1967 .

[32]  Cliff I. Davidson,et al.  The influence of surface structure on predicted particle dry deposition to natural grass canopies , 1982 .

[33]  D. Bache.  Analysing particulate deposition to plant canopies , 1981 .

[34]  K. W. Nicholson.  Wind tunnel experiments on the resuspension of particulate material , 1993 .

[35]  C. N. Davies,et al.  The Mechanics of Aerosols , 1964 .

[36]  Leiming Zhang,et al.  A review of current knowledge concerning size-dependent aerosol removal , 2006 .

[37]  Andrew P. Morse,et al.  Measurements of the Size Dependence of Cloud Droplet Deposition at a Hill Site , 1988 .

[38]  B. Hicks,et al.  A field investigation of sulfate fluxes to a deciduous forest , 1989 .

[39]  W. Tollmien,et al.  Über Flüssigkeitsbewegung bei sehr kleiner Reibung , 1961 .

[40]  P. Schuepp,et al.  Tansley Review No. 59 Leaf boundary layers. , 1993, The New phytologist.

[41]  A. Druilhet,et al.  The Landes experiment: Biosphere‐atmosphere exchanges of ozone and aerosol particles above a pine forest , 1994 .

[42]  J. Finnigan,et al.  Coherent eddies and turbulence in vegetation canopies: The mixing-layer analogy , 1996 .

[43]  Eiko Nemitz,et al.  An Eddy-Covariance System for the Measurement of Surface/Atmosphere Exchange Fluxes of Submicron Aerosol Chemical Species—First Application Above an Urban Area , 2008 .

[44]  J. Monteith,et al.  Principles of Environmental Physics , 2014 .

[45]  J. Finnigan,et al.  A wind tunnel study of air flow in waving wheat: Two-point velocity statistics , 1994 .

[46]  B. Legg,et al.  Spore dispersal in a barley crop: A mathematical model , 1979 .

[47]  A. C. Chamberlain,et al.  Transport of gases to and from grass and grass-like surfaces , 1966, Proceedings of the Royal Society of London. Series A. Mathematical and Physical Sciences.

[48]  T. Bouvet,et al.  An approximate analytical solution for the deposition of heavy particles released from an elevated line source , 2006 .

[49]  K. Peters,et al.  Modelling the dry deposition velocity of aerosol particles to a spruce forest , 1992 .

[50]  Ü. Rannik,et al.  Interpretation of aerosol particle fluxes over a pine forest: Dry deposition and random errors , 2003 .

[51]  R. A. Antonia,et al.  Rough-Wall Turbulent Boundary Layers , 1991 .

[52]  E. F. Bradley,et al.  Flux-Gradient Relationships in a Forest Canopy , 1985 .

[53]  E. Pohlhausen,et al.  Der Wärmeaustausch zwischen festen Körpern und Flüssigkeiten mit kleiner reibung und kleiner Wärmeleitung , 1921 .

[54]  F. Anselmet,et al.  Aerosol dry deposition on vegetative canopies. Part I: Review of present knowledge , 2008 .

[55]  Y. Belot,et al.  Uptake of small particles by tree canopies , 1994 .

[56]  Martin Gallagher,et al.  Measurements and parameterizations of small aerosol deposition velocities to grassland, arable crops, and forest: Influence of surface roughness length on deposition , 2002 .

[57]  R. Shaw,et al.  Aerodynamic roughness of a plant canopy: A numerical experiment , 1982 .

[58]  J. Landsberg,et al.  Surface exchange characteristics of leaves subject to mutual interference , 1973 .

[59]  S. Friedlander,et al.  Aerosol and gas deposition to fully rough surfaces: Filtration model for blade-shaped elements , 1982 .

[60]  Karl J. Niklas,et al.  Plant Biomechanics: An Engineering Approach to Plant Form and Function , 1993 .

[61]  M. Reeks.  The transport of discrete particles in inhomogeneous turbulence , 1983 .

[62]  D. Fowler,et al.  Measurements and parameterisations of small aerosol deposition velocities to grassland, arable crops and forest , 2002 .

[63]  Ü. Rannik,et al.  Vertical aerosol fluxes measured by the eddy covariance method and deposition of nucleation mode particles above a Scots pine forest in southern Finland , 2000 .

[64]  A. B. Hedley,et al.  particle deposition behaviour from turbulent flows , 1984 .

[65]  N. B. Wood.  A simple method for the calculation of turbulent deposition to smooth and rough surfaces , 1981 .

[66]  N. Goel,et al.  Two-Dimensional Leaf Orientation Distributions , 1985, IEEE Transactions on Geoscience and Remote Sensing.

[67]  Bruno Moulia,et al.  A frequency lock-in mechanism in the interaction between wind and crop canopies , 2006, Journal of Fluid Mechanics.

[68]  B. Wiman,et al.  Aerosol depletion and deposition in forests ― a model analysis , 1985 .

[69]  A. Guha.  Transport and Deposition of Particles in Turbulent and Laminar Flow , 2008 .

[70]  J. Grace,et al.  The Boundary Layer over a Populus Leaf , 1976 .

[71]  S. Larsen,et al.  Particle fluxes over forests: Analyses of flux methods and functional dependencies , 2007 .

[72]  M. Wesely,et al.  Measurements and parameterization of particulate sulfur dry deposition over grass , 1985 .

[73]  Patrick Meir,et al.  Light distribution and foliage structure in an oak canopy , 1999, Trees.

[74]  John S. Young,et al.  A theory of particle deposition in turbulent pipe flow , 1997, Journal of Fluid Mechanics.

[75]  A. Ibbetson,et al.  Boundary-layer resistances of artificial leaves in turbulent air: I. Leaves parallel to the mean flow , 1988 .

[76]  S. Pryor.  Size-resolved particle deposition velocities of sub-100 nm diameter particles over a forest , 2006 .

[77]  J. R. Garratt,et al.  Surface influence upon vertical profiles in the atmospheric near-surface layer , 1980 .

[78]  H. Schlichting.  Boundary Layer Theory , 1955 .