Boundary layer atmospheric

Lenschow, D. H. (ed.), "Probing the Atmospheric Boundary Layer." American Meteorological Society, Boston, 1986. 

Randerson, D., 1984. Atmospheric Boundary Layer. In Atmospheric Science and Power Production. Randerson, D. (ed.), DOE/TIC-27601, U.S. Department of Energy, Washington, D.C. 

ESDU Data Item 82026. 1982. Strong Winds in the Atmospheric Boundary Layer—Part 1 Mean Hourly Wind Speeds. Engineering Sciences Data Unit International, London. 

Flow in the atmospheric boundary layer is turbulent. Turbulence may be described as a random motion superposed on the mean flow. Many aspects of turbulent dispersion are reasonably well-described by a simple model in which turbulence is viewed as a spectrum of eddies of an extended range of length and time scales (Lumley and Panofsky 1964). 

VII. Msteorological Parameters Characterizing the Atmospheric Boundary Layer... 

When the turbulence in the atmospheric boundary layer is maintained largely by buoyant production, the boundary layer is said to be in a convective state. The source of buoyancy is the upward heat flux originating from the ground heated by solar radiation. Convective turbulence is relatively vigorous and causes rapid vertical mixing in the atmospheric boundary layer. 

Sections IX,A-C have been devoted to expressions for m(z), (z), and Kyy based on atmospheric boundary layer theory. Because of the rather complicated dependence of u and K onz, Eq. (9.36) must generally be solved numerically (see, for example, Nieuwstadt and van Ulden, 1978 van Ulden, 1978). However, if they can be found, analytical solutions are advantageous for studying the behavior of the predicted mean concentration. 

Counihan, J. (1975). Adiabatic atmospheric boundary layers A review and analysis of data from the period 1880-1972. Atmos. Environ. 9, 871-905. 

Fichtl, G. D., and McVehil, G. E. (1970). Longitudinal and lateral spectra of turbulence in the atmospheric boundary layer at the Kennedy Space Center. J. Appl. Meteorol. 9,51-63. 

Yamada, T. (1977). A numerical experiment on pollutant dispersion in a horizontally-homo-geneous atmospheric boundary layer. Atmos. Environ. 11, 1014-1024. 

Zeman, O., and Tennekes, H. (1977). Parameterization of the turbulent energy budget at the top of the daytime atmospheric boundary layer. J. Atmos. Sci. 34, 111-123. 

Egan, B. A., and J. R. Mahoney. Applications of a numerical air pollution transport model to dispersion in the atmospheric boundary layer. J. Appl. Meteorol. 11 1023-1039, 1972. 

Eq. 7.2, where is then the eddy diffusion coefficient (Taylor and Spencer 1990). The height of the turbulent zone, within the atmospheric boundary layer, is orders of magnitude greater than that of the laminar flow layer, and dispersion of contaminant vapors in the turbulent zone is relatively rapid. 

Several laboratory studies have contributed to our understanding of turbulent chemical plumes and the effects of various flow configurations. Fackrell and Robins [25] released an isokinetic neutrally buoyant plume in a wind tunnel at elevated and bed-level locations. Bara et al. [26], Yee et al. [27], Crimaldi and Koseff [28], and Crimaldi et al. [29] studied plumes released in water channels from bed-level and elevated positions. Airborne plumes in atmospheric boundary layers also have been studied in the field by Murlis and Jones [30], Jones [31], Murlis [32], Hanna and Insley [33], Mylne [34, 35], and Yee et al. [36, 37], In addition, aqueous plumes in coastal environments have been studied by Stacey et al. [38] and Fong and Stacey [39], The combined information of these and other studies reveals that the plume structure is influenced by several factors including the bulk velocity, fluid environment, release conditions, bed conditions, flow meander, and surface waves. 

Equation (8.83) provides us with an expression for the gas him coefficient for an atmospheric boundary layer ... 

Although the focus of this chapter is tropospheric HO measurements, it is worthwhile to mention techniques that have proven useful in the laboratory or in other regions of the atmosphere. As a small molecule in the gas phase, HO has a much-studied and well-understood discrete absorption spectrum in the near UV (29), shown in Figure 1, that lends itself to a variety of absorption and fluorescence techniques. The total atmospheric HO column density has been measured (30-32) from absorption of solar UV radiation, observed with a high-resolution scanning Fabry-Perot spectrometer. Long-path measurements of stratospheric HO from its thermal emission spectra in the far infrared have been reported (33-35). Long absorption paths in the atmospheric boundary layer have been used for HO detection from its UV absorption (36-42). 

Above the atmospheric boundary layer, the vertical temperature gradient is often close to its moist adiabatic value (Betts 1982 Xu and Emanuel 1989), implying the near invariance of the saturation moist static energy ... 

As Brenguier (2003) noted, a contributing factor to the uncertainty is drizzle in clouds that form in the atmospheric boundary layer (ABL). In particular, this circumstance illustrates the importance of the adequate retrieval of cloud cover dynamics in the ABL. Another problem is connected with consideration (parameterization) of small-scale processes in the ABL and their non-linearity. For instance, aerosols acting as cloud concentration nuclei (CCN) can be determined from upward motions at the cloud bottom which should be reproduced at a spatial resolution (in the horizontal) of the order of 100 m. The present parameterization schemes still do not meet these requirements. 

The second stage realizes a two-step procedure that re-calculates the ozone concentration over the whole space S = (tp, A, z) (, A)e l 0atmospheric motion. This division is made for convenience, so that the user of the expert system can choose a synoptic scenario. According to the available estimates (Karol, 2000 Kraabol et al., 2000 Meijer and Velthoven, 1997), the processes involved in vertical mixing prevail in the dynamics of ozone concentration. It is here that, due to uncertain estimates of Dz, there are serious errors in model calculations. Therefore the units CCAB, MFDO, and MPTO (see Table 4.9) provide the user with the principal possibility to choose various approximations of the vertical profile of the eddy diffusion coefficient (Dz). 

Kuck L.R. Balsley B.B. Helmig D. Conway T.J. Tans P.P. Davis K. Jensen M.L. Bognar J.A. Arrieta R.V. Rodriquez R. and Birks J.W. (2000). Measurements of landscape-scale fluxes of carbon dioxide in the Peruvian Amazon by vertical profiling through the atmospheric boundary layer. Journal of Geophysical Research, 105(D17), 22137-22146. 

Marine Atmospheric Boundary Layer Measurement of Air Pollution from Satellites Mapped Atmosphere-Plant-Soil System MODIS Airborne Simulator... 

The production of volatile reduced sulfur compounds in marine ecosystems and the subsequent efflux of these compounds to the marine atmospheric boundary layer is an important source of sulfur to the global atmosphere (1). Independent of its role in the atmospheric sulfur budget, Charlson et al. (2) have suggested that dimethylsulfide (DMS) also plays a major role in cloud formation over oceans. Oxidation products of DMS appear to serve as sites for cloud nucleation. 

If DMS concentrations at the surface of the ocean are presumed to be at steady state, production must balance loss. The fate of DMS is thought to be evasion across the sea surface into the marine atmospheric boundary layer. However, since rates of DMS production are unknown, it is impossible to compare production with flux to the atmosphere, which is relatively well constrained. An alternative sink for DMS in seawater is microbial consumption. The ability of bacteria to metabolize DMS in anaerobic environments is well documented (32-341. Data for aerobic metabolism of DMS are fewer (there are at present none for marine bacteria), but Sivela and Sundman (25) and de Bont et al. (25) have described non-marine aerobic bacteria which utilize DMS as their sole source of carbon. It is likely that bacterial turnover of DMS plays a major role in the DMS cycle in seawater. 

Night-time emission rates in rural and urban areas are listed in Table I together with initial concentrations and land deposition velocities. The initial concentrations were chosen to reflect unpolluted air arriving at the West Coast of England. Methane is assumed to be present in the atmospheric boundary layer at a constant concentration of 1.6 ppm. Water vapour is also assumed to be invariant in rural and urban air at a concentration of 104 ppm. This corresponds to ca. 60% relative humidity at 288 K. The initial concentration and emission over land of DMS have been taken to be zero as have all other species in the chemical scheme which are not listed in Table I. Emissions over land of NO, SO hydrocarbons, CO and H are subject to diurnal variation and this has been treated as before (13.141. Rural emission rates are assumed to prevail throughout the traversal of Scandinavia. All species are assumed to be hilly mixed within an atmospheric boundary layer of constant depth, taken to be... 

Dry deposition is frequently the main sink for ozone in the rural atmospheric boundary layer. What is the lifetime of ozone with respect to this process ... 

Farrar, N.J., Hamer, T., et al. (2004a) Field deployment of thin film passive air samplers for persistent organic pollutants a study in the urban atmospheric boundary layer. Environmental Science and Technology, 39(1) 42-A8. 

Li, Y, Zhang, Q., et al (2009) Levels and vertical distributions of PCBs, PBDEs, and OCPs in the atmospheric boundary layer observation from the Beijing 325-m Meteorological Tower. Environmental Science and Technology, 43(4) 1030-1035. 

The physics package consists of a comprehensive set of physical parametrization schemes (Benoit et al. 1989). Specifically, the atmospheric boundary layer (ABE) is based on a prognostic equation for TKE. The surface temperature over land surface is calculated using the force-restore method combined with a stratified surface layer. Deep convective processes are handled by a Kuo-type convective parametrization (Kuo 1974) for the resolutions that we have adopted for this study. 

The horizontal and vertical resolutions of the model depend on a resolution of the meteorological and emission data. At present the model run over a 0.2° x 0.2° horizontal grid (Fig. 16.3b), and it has a vertical resolution of 25 levels. These vertical levels cover the lowest 3 km of the troposphere. The amount of chemical compounds, which is transported from the free troposphere into the atmospheric boundary layer, is determined by the meteorological information and the concentration of the chemical compounds in the free tropospheric. These concentrations depend on the longitude, latitude, land/sea and month (Gross et al. 2005). The advection is solved using the Bott and PPM schemes (Bott 1989 Colella 1984). 

Improved parametrization of urban effects on the atmospheric boundary layer (BL) is needed. NWP/MM models despite their increased resolution, still have shortcomings. For instance, the description of sub-surface, surface and urban BL for urban areas is similar to that of rural areas. Thus, the urban dynamics and energetics are not properly described. NWP/MM models are not primarily developed for air pollution modelling, and their outputs have to be made suitable to provide input for urban-scale ACTMs. 

---