Transport meteorological bases

The multimedia urban model (MUM) is a fugacity-based mass balance model that treats the movement of POPs in an urban environment and links emissions to ambient chemical concentrations, and thus outdoor exposure (Diamond et al., 2001). MUM considers longterm, average conditions of chemical transport and transformation among six environmental compartments in urban areas (air, soil, surface water, sediment, vegetation and surface film see Figure 6.1) shows a concepmal version of the model). The model does not estimate event-specihc processes as do meteorological-based air or stormwater models. 

The ozone balance in the stratosphere is determined through complex interactions of solar radiation, meteorological movements within the stratosphere, transport to and from the troposphere, and the concentration of species based on elements other than oxygen that enter the stratosphere by natural or artificial means (such as flight of aircraft). 

Dose Projections A computed estimate of the potential dose to individuals at a given location. The projection is based upon the amount of pollutant released from a source or multiple sources and prevailing meteorological transport and dispersion parameters. 

A thorough analysis of atmospheric transport and deposition to the Great Lakes has been carried out using the HYSPLIT model developed by the US National Atmospheric and Oceanic Administration (NOAA) [28,29]. An emissions inventory of PCDD/Fs for North America in 1996 was used as input to the model. Factors considered in the fate and distribution were meteorological data, vapor-particle partitioning, aerosol characteristics, reaction with hydroxyl radicals, photolysis, and dry and wet deposition. The model was generally satisfactory at estimating fluxes, except for HpCDD and OCDD, which appeared to be underestimated by about a factor of four. The model output was summarized as 2378-TeCDD toxic equivalent concentrations (TEQs) based on the WHO mammalian 2378-TeCDD toxic equivalent factors (TEFs) [30]. Since HpCDD and OCDD were estimated to contribute only 2% of TEQs, the model was considered to be valid for the purpose intended. 

Enviro-HIRLAM is an online coupled meteorological, chemical transport and dispersion model. It is based on a previous version HlRLAM-tracer and at its core lies DMI-HIRLAM, version 6.3.7 employed for limited area short range operational weather forecasting at DM1 (Chenevez et al. 2004). Eor a detailed description of the features in HIRLAM the reader is referred to the HIRLAM reference guide (Unden et al. 2002). 

The meteorological input required in the Unified EMEP model are the 3D horizontal and vertical wind fields, specific humidity, potential temperature cloud cover, and precipitation. The transferred surface 2D fields for use in the chemical transport model are surface pressure, 2 m temperature, surface flux of momentum, sensible and latent heat, and surface stress. All variables are given in 3-h interval. Table 13.1 lists the variables and their main purposes in the EMEP model. Inside the model different boundary layer parameters like the stability, eddy diffusion, and mixing height are calculated based on MOST. 

The Atmospheric Chemistry Transport modelling system used is based on the off-line coupled CAMx and HIRLAM models has been developed to simulate particulate and gas-phase air pollution on different scales. It has been used to simulate short and longterm releases of different chemical species and air pollution episodes. At present it is run in a pre-operational mode 4 times per day based on 3D meteorological fields produced by the HIRLAM NWP model. Currently this modelling system is setup to perform chemical weather forecasts for a series of chemical species (such as O3, NO, NO2, CO and SO2) and forecasted 2D fields at surface are available for each model as well as an ensemble of models (based on 12 European regional air quality models). The simulated output is publicly available and it is placed at the ECMWF website (http //gems.ecmwf.int/d/products/raq/forecasts/) of the EC FP6 GEMS project. 

As far as I can tell by talking with contemporary thermo-dynamicists, especially those who grew up with the traditions of classical thermodynamics, these revolutionary ideas have had very little effect on them. But the impacts of the Shannon and Jaynes papers on others has been most dramatic. A few months ago I ordered a computer search of one particular data base. We looked for all papers published between 1970 and 1975 in which Shannon or Jaynes or both appeared as references. There were over 400 literature citations in such fields as systems theory, biology, neurology, meteorology, statistical mechanics, thermodynamics, irreversible processes, reliability, geology, psychiatry, communications theory and even urban studies, transportation and architecture. 

The other component is directed toward estimation of the capacity of the region to accept industrial development—the regional carrying capacity—based on the meteorological characteristics of the region. More specific needs are (1) more accurate atmospheric models to predict the transport and dispersion of atmospheric pollutants, (2) determining rates at which pollutants are removed from the atmosphere, and (3) quantitative information on the effects of air pollutants on critical atmospheric processes related to undesirable effects, e.g., precipitation quality, decreased visibility, and local climate modification. ... 

Benarie (1987) discusses errors in Gaussian and other atmospheric dispersion models for neutral or positive buoyancy releases. He highlights the randomness of atmospheric transport processes and the importance of averaging time. The American Meteorological Society (1978) has stated that the precision of models based on observation is closely tied to the scatter of that data. At present the scatter of meteorological data is irreducible and dispersion estimates can approximate this degree of scatter only in the most ideal circumstances. 

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