Troposphere distribution

While detailed transport calculations of trace constituent distributions in the troposphere are not generally available, a number of simple box models have been fitted to measurements of seasonal fluctuations in carbon dioxide and ozone and tropospheric distributions of fission debris. These box models may not accurately represent the physical processes responsible for tropospheric motions and mixing, but the parameters used in the model do provide reasonable estimates of macroscopic mixing rates in the troposphere. 

Montzka, S.A., R.C. Myers, J.H. Butler, J.W. Elkins, and S.O. Cummings, Global tropospheric distribution and calibration scale of HCFC-22, Geophys Res Lett 20, 703, 1993. 

Smythe, S., et al. (1996) Factors influencing the upper free tropospheric distribution of reactive nitrogen over the South Atlantic during the TRACE-A experiment. J. Geophys. Res., 101, 1743-1762. 

Weiss, R. F. (1981). The temporal and spatial distribution of tropospheric nitrous oxide. /. Geophys. Res. 86, 7185-7195. 

Denmark 1.5 days after the explosion. Air samples collected at Roskilde, Denmark on April 27-28, contained a mean air concentration of 241Am of 5.2 pBq/m3 (0.14 fCi/m3). In May 1986, the mean concentration was 11 pBq/m3 (0.30 fCi/m3) (Aarkrog 1988). Whereas debris from nuclear weapons testing is injected into the stratosphere, debris from Chernobyl was injected into the troposphere. As the mean residence time in the troposphere is 20-40 days, it would appear that the fallout would have decreased to very low levels by the end of 1986. However, from the levels of other radioactive elements, this was not the case. Sequential extraction studies were performed on aerosols collected in Lithuania after dust storms in September 1992 carried radioactive aerosols to the region from contaminated areas of the Ukraine and Belarus. The fraction distribution of241 Am in the aerosol samples was approximately (fraction, percent) organically-bound, 18% oxide-bound, 10% acid-soluble, 36% and residual, 32% (Lujaniene et al. 1999). Very little americium was found in the more readily extractable exchangeable and water soluble and specifically adsorbed fractions. 

Hoppel, W.A., Measurement of the Mobility Distribution of Tropospheric Ions, Pure and App. Geophvs. 81 230-245 (1970). 

Spivakovsky CM, Logan JA, Montzka SA, Balkanski YJ, Foreman-Fowler M, Jones DBA, Horowitz LW, Fusco AC, Brenninkmeijer CAM, Prather MJ, Wofsy SC, McElroy MB (2000) Three-dimensional climatological distribution of tropospheric OH Update and evaluation. J Geoph Res 105(D7) 8931-8980... 

Raes, F., VanDingenen, R., Cuevas, E., VanVelthoven, P. F. J., and Prospero, J. Observations of aerosols in the free troposphere and marine boundary layer of the subtropical Northeast Atlantic Discussion of processes determining their size distribution, J. Geophys. Res.-A., 102, 21 315-21 328,1997. 

Fabian, P.. and P. G. Pruchniewicz. Meridional distribution of tropospheric ozone from ground-based registrations between Norway and South Africa. Pure Appl. Geophys. 106-108 1027-1035, 1973. 

DeLorey DC, Cronn DR, Farmer JC. 1988. Tropospheric latitudinal distributions of CFCK CFCh, N2 0, CH3CC 3, and CCH over the remote Pacific Ocean. Atmos. Environ 22 1481-1494. 

As discussed in Chapter 6.J, acetone photochemistry is of interest because this ketone is distributed globally, has both biogenic and anthropogenic sources, and has been proposed to be a significant source of free radicals in the upper troposphere. The absorption cross sections of acetone (as well as other aldehydes and ketones) are temperature dependent at the longer wavelenths, which is important for application to the colder upper troposphere. Figure 4.29, for example, shows the absorption cross sections of acetone at 298 and 261 K, respectively (Hynes et al., 1992 see also Gierczak et al., 1998). 

NASA also carries out kinetic evaluations for reactions of interest in the stratosphere (although many of them are also important in the troposphere) (DeMore et al., 1997). This document can be obtained from the Jet Propulsion Laboratory (California Institute of Technology, Document Distribution, MS 512-110, 4800 Oak Grove Drive, Pasadena, CA 91109) or through the Internet (see Appendix IV). 

Cros, B D. Nganga, A. Minga, J. Fishman, and V. Brackett, Distribution of Tropospheric Ozone at Brazzaville, Congo, Determined from Ozonesonde Measurements, J. Geophys. Res., 97, 12869-12875 (1992). 

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