Dr. W. Richard Leaitch

Research Scientist - Study Leader
Environment and Climate Change Canada

Current research and/or projects

Studies of the impact of aerosol particles on climate

  • aerosol-cloud interactions
  • chemistry and physics of aerosol particles
  • field observations: intensive and long-term
  • imporvements in atmospheric prediction at large scales

Professional activities / interests


Lead author, 2001 IPCC Third Assessment Report

Lead scientist for aerosol process and effects studies at EC baseline aerosol measurement sites

Co-supervised 12 graduate students

Editor, Advances in Meterology

Education and awards

1971‑1975, BSc. Honours Physics, University of Waterloo

1975‑1981, PhD. Physics, York University

Key publications

Leaitch, W.R., Strapp, J.W., Isaac, G.A., and Hudson, J.G. 1986. Cloud droplet nucleation and cloud scavenging of aerosol sulphate in polluted atmospheres.  Tellus. 38B: 328‑344.

Leaitch, W.R., Isaac, G.A., Strapp, J.W., Banic, C.M., and Wiebe, H.A. 1992. The relationship between cloud droplet number concentrations and anthropogenic pollution: observations and climatic implications.  J. Geophys. Res., 97: 2463-2474.

Leaitch, W.R., Banic, C.M., Isaac, G.A., Couture, M.D., Liu, P.S.K., Gultepe, I., Li, S.-M., Kleinman, L.I., Daum, P.H. and MacPherson, J.I. 1996. Physical and chemical observations in marine stratus during 1993 NARE:  Factors controlling cloud droplet number concentrations,  Journal of Geophys. Res. 101: 29123-29135.

Leaitch, W.R., J.W. Bottenheim, T.A. Biesenthal, S.-M. Li, P.S.K. Liu, K. Asalian, H. Dryfhout-Clark, F. Hopper, and F.J. Brechtel. 1999. A case study of gas-to-particle conversion in an eastern Canadian forest. J. Geophys. Res. 104: 8095-8111.

Leaitch, W.R., A.M. Macdonald, K.G. Anlauf, P.S.K. Liu, D. Toom-Sauntry, S.-M. Li, J. Liggio, K. Hayden, M.A. Wasey, L.M. Russell, S. Takahama, S. Liu, A. van Donkelaar, T. Duck and R.V. Martin, Q. Zhang, Y. Sun, I. McKendry, M. Cubison. 2009. Evidence for Asian Dust Effects from Aerosol Plume Measurements during INTEX-B 2006 near Whistler, BC. Atmos. Chem. Phys. 9: 3523-3546.

Leaitch, W. R., U. Lohmann, L.M. Russell, T. Garrett, N.C. Shantz, D. Toom-Sauntry, J.W. Strapp, K.L. Hayden, J. Marshall, M. Wolde, D.R. Worsnop, and J.T. Jayne. 2010. Cloud albedo increase from carbonaceous aerosol. Atmos. Chem. Phys. 10: 7669-7684.


1996-2004, Adjunct Professor, Department of Physics and Atmospheric Science, Dalhousie University, Halifax, Nova Scotia, Canada

Sept-Dec., 1996, Visiting Scientist, Colorado State University Department of Atmospheric Science

2004 - present, Adjunct Professor, Centre for Research in Earth and Space Sciences, York University, Toronto, Ontario, Canada