Editorial Type:
Article
Article Type:
Research Article

Vertical Diffusion in the Lower Atmosphere Using Aircraft Measurements of 222Rn

H. N. Lee Environmental Measurements Laboratory, U.S. Department of Energy, New York, New York

Search for other papers by H. N. Lee in
Current site
Google Scholar
PubMed Close
and
R. J. Larsen Environmental Measurements Laboratory, U.S. Department of Energy, New York, New York

Search for other papers by R. J. Larsen in
Current site
Google Scholar
PubMed Close
Print Publication:
01 Sep 1997
DOI:
https://doi.org/10.1175/1520-0450(1997)036<1262:VDITLA>2.0.CO;2
Page(s):
1262–1270
Restricted access

Abstract

Vertical profiles of 222Rn concentrations measured from 3 to 6 September 1995 in the northeastern United States, using a new radon instrument designed for aircraft measurements, are presented. A vertical diffusion model was employed to simulate the distributions of 222Rn concentrations by using time-dependent profiles of vertical eddy diffusivity in the lower atmosphere. To determine these profiles, O’Brien’s simple formulation was applied using the diurnal changes of the boundary layer height and surface fluxes. The model-calculated profiles of the 222Rn concentrations were then compared with the aircraft measurements of 222Rn.

Model simulations were also calculated using different values of the vertical eddy diffusivity above the boundary layer. Using the value of kz above the boundary layer equal to 10% of its maximum boundary layer value in the model resulted in the best vertical profiles of the calculated 222Rn compared with the measurements within the boundary layer.

From aircraft measurement data of the naturally occurring radionuclide 222Rn, the vertical mixing processes in the lower atmosphere were studied. These data will be useful for model validations.

Corresponding author address: Dr. H. N. Lee, Environmental Measurements Laboratory, U.S. Department of Energy, 201 Varick Street, 5th Floor, New York, NY 10014-4811.

hnlee@eml.doe.gov

Abstract

Vertical profiles of 222Rn concentrations measured from 3 to 6 September 1995 in the northeastern United States, using a new radon instrument designed for aircraft measurements, are presented. A vertical diffusion model was employed to simulate the distributions of 222Rn concentrations by using time-dependent profiles of vertical eddy diffusivity in the lower atmosphere. To determine these profiles, O’Brien’s simple formulation was applied using the diurnal changes of the boundary layer height and surface fluxes. The model-calculated profiles of the 222Rn concentrations were then compared with the aircraft measurements of 222Rn.

Model simulations were also calculated using different values of the vertical eddy diffusivity above the boundary layer. Using the value of kz above the boundary layer equal to 10% of its maximum boundary layer value in the model resulted in the best vertical profiles of the calculated 222Rn compared with the measurements within the boundary layer.

From aircraft measurement data of the naturally occurring radionuclide 222Rn, the vertical mixing processes in the lower atmosphere were studied. These data will be useful for model validations.

Corresponding author address: Dr. H. N. Lee, Environmental Measurements Laboratory, U.S. Department of Energy, 201 Varick Street, 5th Floor, New York, NY 10014-4811.

hnlee@eml.doe.gov

Save
Cover Journal of Applied Meteorology and Climatology
Journal of Applied Meteorology and Climatology

  • Allen, D. J., R. B. Rood, A. M. Thompson, and R. D. Hudson, 1996: Three-dimensional radon-222 calculations using assimilated meteorological data and a convective mixing algorithm. J. Geophys. Res.,101, 6871–6881.

  • Andren, A., 1990: Evaluation of a turbulence closure scheme suitable for air pollution application. J. Appl. Meteor.,29, 224–239.

  • Balkanski, Y. J., D. J. Jacob, G. M. Gardner, W. C. Graustein, and K. K. Turekian, 1993: Transport and residence times of tropospheric aerosols inferred from a global three-dimensional simulation of 210Pb. J. Geophys. Res.,98, 20 573–20 586.

  • Beck, H. L., and C. V. Gogolak, 1979: Time dependent calculations of the vertical distribution of 222Rn and its decay products in the atmosphere. J. Geophys. Res.,84, 3139–3148.

  • Busch, N. E., S. W. Chang, and R. A. Anthes, 1976: A multi-level model of the planetary boundary layer suitable for use with mesoscale dynamic models. J. Appl. Meteor.,15, 909–919.

  • Butterweck, G., A. Reineking, J. Kesten, and J. Porstendorfer, 1994: The use of the natural radioactive noble gases radon and thoron as tracers for the study of turbulent exchange in the atmospheric boundary layer—Case study in and above a wheat field. Atmos. Environ.,28, 1963–1969.

  • Deardorff, J. W., 1972: Parameterization of the planetary boundary layer for use in general circulation model. Mon. Wea. Rev.,100, 93–106.

  • Dyer, A. J., 1974: A review of flux-profile relationships. Bound-Layer Meteor.,7, 363–372.

  • Feichter, J., R. A. Brost, and M. Heimann, 1991: Three-dimensional modeling of the concentration and deposition of 210Pb aerosols. J. Geophys. Res.,96, 22 447–22 460.

  • Genthon, C., and A. Armengaud, 1995: Radon 222 as a comparative tracer of transport and mixing in two general circulation models of the atmosphere. J. Geophys. Res.,100, 2849–2866.

  • Guedalia, D., C. Allet, and J. Fontan, 1974: Vertical exchange measurements in the lower troposphere using ThB (Pb-212) and Radon (Rn-222). J. Appl. Meteor.,13, 27–39.

  • Hanna, S. R., 1995: Vertical diffusivitykv in Eulerian regional air quality models. Preprints, 11th Symp. on Boundary Layers and Turbulence, Charlotte, NC, Amer. Meteor. Soc., 81–85.

  • Holtslag, A. A. M., and C. H. Moeng, 1991: Eddy diffusivity and countergradient transport in the convective atmospheric boundary layer. J. Atmos. Sci.,48, 1690–1698.

  • ——, and B. A. Boville, 1993: Local versus nonlocal boundary-layer diffusion in a global climate model. J. Climate,6, 1825–1842.

  • Hutter, A. R., and C. V. Gogolak, 1994: Reproducibility of radon-222 flux measurements using the accumulation method. Eos, Trans Amer. Geophys. Union,75, 114.

  • Jacobi, W., and K. Andre, 1963: The vertical distribution of radon-222, radon-220 and their decay products in the atmosphere. J. Geophys. Res.,68, 3799–3814.

  • Lee, H. N., 1992: Second-order closure turbulence model for air pollution studies. Air Pollution Modeling and Its Application, Vol. IX, H. van Dop and G. Kallos, Eds., Plenum Press, 687–694.

  • ——, 1993: A semi-Lagrangian transport scheme with spectral interpolation. J. Appl. Meteor.,32, 1908–1918.

  • ——, 1996: A semi-Lagrangian spectral algorithm for pollutant transport and diffusion studies. J. Appl. Meteor.,35, 2129–2135.

  • ——, and S. K. Kao, 1979: Finite-element numerical modeling of atmospheric turbulent boundary layer. J. Appl. Meteor.,18, 1287–1295.

  • ——, and J. Feichter, 1995: An intercomparison of wet precipitation scavenging schemes and the emission rates of 222Rn for simulation of global transport and deposition of 210Pb. J. Geophys. Res.,100, 253–270.

  • Louis, J. F., 1979: A parametric model of vertical eddy fluxes in the atmosphere. Bound.-Layer Meteor.,17, 187–202.

  • Mellor, G., 1982: Development of a turbulence closure model for geophysical fluid problems. Rev. Geophys. Space Phys.,20, 851–871.

  • ——, and T. Yamada, 1974: A hierarchy of turbulence closure models for planetary boundary layer. J. Atmos. Sci.,31, 1791–1806.

  • Negro, V. C., N. Y. Chiu, R. J. Larsen, S. B. Wurms, and C. Breheny, 1996: Continued testing and evaluation of the Radgrabber. EML 1995 Annual Rep., USDOE Rep. EML-580, 153 pp. [Available from the National Technical Information Service, U.S. Department of Commerce, 5285 Port Royal Road, Springfield, VA 22161.].

  • O’Brien, J. J., 1970: A note on the vertical structure of the eddy exchange coefficient in the planetary boundary layer. J. Atmos. Sci.,27, 1213–1215.

  • OHER, 1993. Atmospheric Chemistry Program, program operation plan, April 1993. DOE/ER-0586T, 96 pp. [Available from National Technical Information Service, U.S. Dept. of Commerce, 5285 Port Royal Road, Springfield, VA 22161.].

  • ——, 1995: Atmospheric Science Program, summaries of research in FY 1994. DOE/ER-0650T, 70 pp. [Available from National Technical Information Service, U.S. Dept. of Commerce, 5285 Port Royal Road, Springfield, VA 22161.].

  • Ramonet, M., J. C. Le Roulley, P. Bousquet, and P. Monfray, 1996: Radon-222 measurements during the Tropoz II campaign and comparison with a global atmospheric transport model. J. Atmos. Chem.,23,107–136.

  • Schery, D. D., S. Whittlestone, K. P. Hart, and S. E. Hill, 1989: The flux of radon and thoron from Australian soils. J. Geophys. Res.,94, 8567–8576.

  • Spicer, C., D. Kenny, W. Shaw, K. Busness, and E. Chapman, 1994: A laboratory in the sky; New frontiers in measurements aloft. Environ. Sci. Technol.,28, 412A–420A.

  • Troen, I., and L. Mahrt, 1986: A simple model of the atmospheric boundary layer; Sensitivity to surface evaporation. Bound.-Layer Meteor.,37, 129–148.

  • Wilkening, M. H., and W. E. Clements, 1975: Radon 222 from the ocean surface. J. Geophys. Res.,80, 3828–3830.

  • ——, ——, and D. Stanley, 1972: Radon-222 flux measurements in widely separated regions. Proc. Second Int. Symp. on the Natural Radiation Environment, Houston, TX, U.S. ERDA, 717–730. [Available from National Technical Information Service, U.S. Dept. of Commerce, 5285 Port Royal Road, Springfield, VA 22161.].

All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 326 122 5
PDF Downloads 129 42 2