Using the turbulent statistical form of the vertical vortex diffusion coefficientK 2 in the planetary boundary layer (PBL) and Ekman spiral wind profile, the three-dimensional diffusion equation is solved by the numerical method. The influences of vertical shear of both wind direction and wind speed on pollution trajectory and horizontal diffusion parameters σ γ are numerically analysed. The expressions of both pollution trajectory and σ γ including the factor of wind shear, are obtained. The results show that the vertical shear of wind is important among all factors affecting the mesoscale dispersion. Specifically, from neutral to stable atmospheric conditions, vertical shear of wind makes greater contribution to σ γ than turbulence, thus it is the most important factor. In this paper, we have compared horizontal dispersion pattern with both Pasquill's dispersion pattern considering wind direction shear, and experimental data collected at 9 different sites ranging from 10 to 100 km, and the results show that our dispersion pattern is closer to the experimental values than Pasquill's results, and his correction to shear of wind direction is too large under the stable conditions.
This is a preview of subscription content, log in to check access.
Buy single article
Instant access to the full article PDF.
Price includes VAT for USA
Smith, F. B.,Proceedings of the conference on mathematical modelling of turbulent diffusion in the environment, held at Livernool University, 1978, 201–236.
Yasuo, Ide, N. U., WMO-No: 510, 1978, 163–169.
Maul, P. R.,Atmos. Environ,12(1978), 1045–1050.
2(1982), 1, 74–79
1(1981), 6, 26–32.
1(1981), 4, 304–312.
1(1981), 3, 30–36.
Chrietiansen, J. H.,Second joint conference on applications of air pollution meteorology, 1980, 627–633.
About this article
Cite this article
Lei, X. Effect of wind vertical shear on diffusion characteristics in the mesoscale range. Adv. Atmos. Sci. 2, 225–233 (1985). https://doi.org/10.1007/BF03179754
- Wind Direction
- Neutral Condition
- Planetary Boundary Layer
- Wind Shear
- Vertical Shear