Tropospheric transport

Mircea M, D Isidoro M, Maurizi A, Vitali L, Monforti F, Zanini G, Tampieri F (2008) A comprehensive performance evaluation of the air quality model BOLCHEM to reproduce the ozone concentrations over Italy. Atmos Environ 42(6) 1169-1185 Tampieri E, Maurizi A (2007) Evaluation of the dispersion coefficient for numerical simulations of tropospheric transport Nuovo Cimento C 30 395 06 Tegen I, Harrison SP, Kohfeld K, Colin Prentice I, Coe M, Heinmann M (2002) J Geophys Res 107 D21. doi 10.1029/2001JD000963... 

Discuss tropospheric transport and deposition of zinc. Compare the deposition rates in land and oceanic areas. 

National Academy of Sciences, 1978. The Tropospheric Transport of Pollutants and Other Substances to the Oceans. National Research Council, Washington, D.C., 243 pp. 

Understanding the Tropospheric Transport and Fate of Semivolatile Pest Management Chemicals... 

Bidleman, T. F. High Molecular Weight Chlorinated Hydrocarbons in the air and sea. Rates and Mechanisms of Air-Sea Transfer. Workshop on Tropospheric Transport of Pollutants to the Ocean. 79, 1975... 

A representation of the stratospheric system that shields terrestrial life from excessive solar ultraviolet radiation is presented in Figure 4. Our primary concern is the decrease of stratospheric ozone, most striking in the Antarctic, which has been linked to increases in CFCs from the troposphere, and the possible increased transport of these compounds between the stratosphere and the troposphere by increased temperature driven circulation. 

Certainly, photochemical air pollution is not merely a local problem. Indeed, spread of anthropogenic smog plumes away from urban centers results in regional scale oxidant problems, such as found in the NE United States and many southern States. Ozone production has also been connected with biomass burning in the tropics (79,80,81). Transport of large-scale tropospheric ozone plumes over large distances has been documented from satellite measurements of total atmospheric ozone (82,83,84), originally taken to study stratospheric ozone depletion. 

Time scales of transport can also be applied to situations when no well-defined reservoirs can be defined. If the dominant transport process is advection by mean flow or sedimentation by gravity, the time scale characterizing the transport between two places is simply tadv = L/V where L is the distance and V the transport velocity. Given a t)q)ical wind speed of 20 m/s in the mid-latitude tropospheric westerlies, the time of transport around the globe would be about 2 weeks. 

The turnover time of water vapor in the atmosphere obviously is a function of latitude and altitude. In the equatorial regions, its turnover time in the atmosphere is a few days, while water in the stratosphere has a turnover time of one year or more. Table 7-1 Qunge, 1963) provides an estimate of the average residence time for water vapor for various latitude ranges in the troposphere. Given this simple picture of vertical structure, motion, transport, and diffusion, we can proceed to examine the behavior of... 

After emission, contaminants may be partitioned among the terrestrial, aqnatic, and various atmospheric phases, and those of sufficient volatility or associated with particles may be transported over long distances. This is not a passive process, however, since important transformations may take place in the troposphere during transit so that attention should also be directed to their transformation products. 

Altshuller, A. P. (1991) Chemical reactions and transport of alkanes and their products in the troposphere. J. Atmos. Chem. 12, 19-61. 

Air pollution in cities can be considered to have three components sources, transport and transformations in the troposphere, and receptors. The sources are processes, devices, or activities that emits airborne substances. When the substances are released, they are transported through the atmosphere, and are transformed into different substances. Air pollutants that are emitted directly to the atmosphere are called primary pollutants. Pollutants that are formed in the atmosphere as a result of transformations are called secondary pollutants. The reactants that undergo the transformation are referred to as precursors. An example of a secondary pollutant is troposphere ozone, O3, and its precursors are nitrogen oxides (NO = NO + NO2) and non-methane hydrocarbons, NMHC. The receptors are the person, animal, plant, material, or urban ecosystems affected by the emissions (Wolff, 1999). 

Ryaboshapko, A., Ilyin, I. (2001). Mercury re-emission to the atmosphere in Europe. In Proceedings of EUROTRAC Symposium 2000 Transport and Chemical Transformation in the Troposphere . 

Aerosol surface area is likely to be variable even within a remote marine air mass. Previous MBL aerosol studies describe changes in aerosol concentration and composition due to entrainment from the free troposphere (Bates et al., 1998, 2001 Covert et al., 1998). Raes et al. (1997) found an observable link between vertical transport patterns and aerosol variability in the MBL specifically in the Aitken mode (<0.2/u.m). Hence entrainment of aerosol from the free troposphere appears to occur frequently, even in remote MBL air masses. In addition, aerosols have the capacity to travel great distances in the free troposphere, before being entrained into the MBL. 

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