EGU General Assembly 2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.

Saharan dust vertical distribution is controlled by convection and scavenging. Why do models miss this?

Romain Pilon2,3, Habib Senghor1, Binta Diallo3, Jeronimo Escribano4, Frederic Hourdin3, Jean-Yves Grandpeix3, Olivier Boucher3, Amadou Thierno Gaye1, and Eric Machu5
Romain Pilon et al.
  • 1Laboratoire de Physique de l’Atmosphère et de l’Océan Simeon-Fongang, Ecole Supérieure Polytechnique de l’Université Cheikh Anta Diop (UCAD)
  • 2University of Lausanne, Institute of Earth Surface Dynamics, Switzerland (
  • 3Laboratoire de Meteorologie Dynamique
  • 4Barcelona Supercomputing Center
  • 5Laboratoire d’Océanographie Physique et Spatiale (LOPS), Université de Brest, IRD, IFREMER

Saharan dust represents more than 50% of the total desert dust emitted around the globe and its radiative effect significantly affects the atmospheric circulation at a continental scale. Atmospheric models often fail to represent the dust vertical distribution and the Saharan Air Layer. They underestimate the effects of deep convection on the vertical transport and of the role of scavenging on the confinement of dust aerosols in this layer. Using multi-year simulations performed with a variable-resolution climate model and processed-based analysis, we show that scavenging in deep convection and further re-evaporation of dusty rainfall in the lower troposphere are critical processes for explaining the vertical distribution of desert dust. They play a key role in maintaining a well-defined dust layer with sharp transition at the top of the SAL and in establishing the seasonal cycle of dust distribution.

How to cite: Pilon, R., Senghor, H., Diallo, B., Escribano, J., Hourdin, F., Grandpeix, J.-Y., Boucher, O., Gaye, A. T., and Machu, E.: Saharan dust vertical distribution is controlled by convection and scavenging. Why do models miss this?, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-2754,, 2022.

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