Aerosol model

Wexler, A. S., and J. H. Seinfeld, Second-Generation Inorganic Aerosol Model, Atmos. Environ., 25A, 2731-2748 (1991). 

Also special care should be taken to reduce uncertainties on emission data and measurements. The validation of an aerosol model requires the analysis of the aerosol chemical composition for the main particulate species (ammonium, sulphate, nitrate and secondary organic aerosol). To find data to perform this kind of more complete evaluation is not always easy. The same applies to emissions data. The lack of detailed information regarding the chemical composition of aerosols obliges modellers to use previously defined aerosols components distributions, which are found in the literature. Present knowledge in emission processes is yet lacunal, especially concerning suspension and resuspension of deposited particles [37]. 

Aksoyoglu S, Keller J, Barmpadimos I, Oderbolz D, Lanz VA, Prevot ASH, Baltensperger U (2011) Aerosol modelling in Europe with a focus on Switzerland during summer and winter episodes. Atmos Chem Phys 11 7355-7373... 

The submicron particle number size distribution controls many of the main climate effects of submicron aerosol populations. The data from harmonized particle number size distribution measurements from European field monitoring stations are presented and discussed. The results give a comprehensive overview of the European near surface aerosol particle number concentrations and number size distributions between 30 and 500 nm of dry particle diameter. Spatial and temporal distributions of aerosols in the particle sizes most important for climate applications are presented. Annual, weekly, and diurnal cycles of the aerosol number concentrations are shown and discussed. Emphasis is placed on the usability of results within the aerosol modeling community and several key points of model-measurement comparison of submicron aerosol particles are discussed along with typical concentration levels around European background. 

Giorgi F. Bi X. and Qian Y. (2003). Indirect and direct effects of anthropogenic sulfate on the climate of East Asia as simulated with a regional coupled climate-chemistry/aerosol model. Climatic Change, 58, 345-376. 

The quantum mechanical/molecular mechanical aerosol model was developed to describe the interaction between gas phase molecules and atmospheric particles. This method has been utilized for the calculation of interaction energies and... 

In a guinea pig/aerosol model, 6 x 10 spores of the vaccine anthrax strain STI were detected in the lungs 1 h after infection from a dose of 2.43 x 10 spores. Bacillus anthracis was not detectable in the tracheobronchial lymph nodes until 2 days post-infection. On day 36 post-infection, lung levels were down to 10 spores and tracheobronchial lymph nodes were again negative. 

MADRID secondary organic aerosol model (SORGAM) The model of aerosol dynamics, reaction, ionization, and dissolution... 

The NWP-CHEM gas-phase chemistry scheme (Korsholm 2009) was developed at the DMI for usage in online models. The scheme contains 17 advected gas-phase species and 20 reactions. Photolysis reaction rates are based on Poppe et al. (1996). A modal aerosol model with three log-normal modes, developed at DMI, will be used to treat aerosol physics (Goss and Baklanov 2004 Korsholm 2009). 

The choice of the chemical and aerosol models for using with or implementation into HIRLAM/HARMONIE depends on specific tasks (e.g. for atmospheric pollution or for improvement of NWP). Current ACTMs of HIRLAM institutes (e.g. DACFOS, EMEP, MATCH, SELAM, etc.) are problem-oriented (air quality) and not very flexible for simple modifications. In CAC and Enviro-HIRLAM different... 

Table 2 - Characteristic Values of the Parameters of Aerosol Model. a Two-Mode Arctic...

Kondratyev K. Ya and Pozdnyakov D.V., Aerosol models of the atmosphere. Moscow, Nauka Publ. House, 1981, 104 pp. (in Russian). 

Hand,. L., Mahowald, N. M., Chen, Y., Siefert, R. L., Luo, C., Subramaniam, A., and Fung, I. (2004). Estimates of atmospheric-processed soluble iron from observations and a global mineral aerosol model Biogeochemical implications. J. Geophys. Res. Atmos. 109, D17205. 

Accurate representation of these processes must treat particle size, morphology, and composition. This requirement contrasts with the present situation in which large-scale aerosol models for the most part treat the particle composition as uniform, with properties corresponding to spherical particles having a uniform composition and single effective radius. Studies of individual particles show particles are more complex and that these assumptions are too approximate (e.g., Buseck and Posfai, 1999 Buseck et al., 2002). In practice, much of the information required to represent aerosol evolution is not known. However, levels of accuracy must be balanced against feasibility and complexity of model appropriate to the problem at hand. 

A major complexity in aerosol modeling is representation of the size and composition distributions and their temporal evolution. Continuous, sectional, modal, moment-based, and hybrid approaches have been used. 

Despite concerns over assumptions and approximations, size-resolved, multicomponent aerosol models are being employed at a variety of scales. An example at the scale of an urban air-shed is the study of Meng et al. (1998), which examined aerosol composition and size distribution for the South Coast Air Basin of California. Modeled aerosol substances included SO , NOf, NHJ, Na, CP, and secondary organics. Gas-phase... 

Wilck M. and Stratmann F. (1997) A 2-D multicomponent modal aerosol model and its application to laminar flow reactors. J. Aerosol. Sci. 28, 959-972. 

These parameters are some of the most important needed for developing an aerosol model, but by no means all of them. Most likely, temperature of the sea surface and air, height of the mixing layer, and sea surface roughness also need to be known. 

The aerosol toxicity of ricin has been documented in several laboratory animals, including rhesus (Wilhelmsen and Pitt, 1996) and African green monkeys, but it remains unclear which, if any, of these effectively model the human response to ricin. Is it necessary to conduct animal trials with medical countermeasures for ricin in an NHP aerosol model, or will other animal models suffice to predict the human response The unexpected appearance of VLS in human clinical trials underscores the difficulty in extrapolating from animal models. Data addressing these questions will be critical in devising practical and effective strategies for coping with ricin as a toxin weapon. 

Middleton, P., and C. S. Kiang (1978). A kinetic aerosol model for the formation and growth of secondary sulfuric and acid particles. J. Aerosol Sci. 9, 359-385. 

Solution of (10.96) for a given temperature requires calculation of the corresponding molalities. These concentrations depend not only on the aerosol nitrate and ammonium but also on the amount of water in the aerosol phase. Therefore calculation of the aerosol solution composition requires estimation of the aerosol water content. As we have seen in Section 10.2.1, the water activity will be equal to the relative humidity (expressed in the 0-1 scale). While this is very useful information, it is not sufficient for the water calculation. One needs to relate the tendency of the aerosol components to absorb moisture with their availability and the availability of water given by the relative humidity. In atmospheric aerosol models (Hanel and Zankl 1979 Cohen et al. 1987 Pilinis and Seinfeld 1987 Wexler and Seinfeld 1991) the water content of aerosols is usually predicted using the ZSR relationship (Zdanovskii 1948 Stokes and Robinson 1966)... 

Wexler, A., and Hasegawa, S. (1954) Relative humidity-temperature relationships of some unsaturated salt solutions in the temperature range 0 to 50°C, J. Res. Nat. Bur. Std. 53, 19-26. Wexler, A. S., and Seinfeld, J. H. (1991) Second-generation inorganic aerosol model, Atmos. Environ. 25A, 2731-2748. 

Pilinis, C., and Seinfeld, J. H. (1988) Development and evaluation of an Eulerian photochemical gas-aerosol model, Atmos. Environ. 22, 1985-2001. 

Brown, D.P., Rubin, S.G., and Biswas, P. (1995). Development and Demonstration of a Two/Three Dimensional Coupled Flow and Aerosol Model, In Proceedings of the I3lh AIAA Applied Aerodynamics Conference, American Institute of Aeronautics and Astronautics. 

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