Warm Fog Elimination by Seeding with Salty Drops: Experiments and Theory


  • Alexander Khain The Hebrew University of Jerusalem
  • Mark Pinsky The Hebrew University of Jerusalem
  • Ehud Gavze The Hebrew University of Jerusalem
  • Ayala Ronen The Israel Institute for Biological Research
  • Smuel Elisha The Israel Institute for Biological Research
  • Ofir Shoshanim The Israel Institute for Biological Research
  • Pavel Khain The Israel Meteorological Service




A method for warm fog elimination by seeding with salty drops was tested in a fog chamber in laboratory experiments, a field experiment, and by a geometrically simple numerical model with an accurate calculation of condensational growth and evaporation of fog droplets and seeding salty drops. The laboratory experiments, conducted in a 3 × 3 × 2.7 m fog chamber, showed an increase in visibility from a few meters to about 100 m in several seconds after seeding.  A field experiment in which natural fog was seeded with salty drops ejected for 10 s over an area of 6 × 6 m from heights of 3 and 10 m showed a substantial increase in visibility for about 1.5-2 min. The limited duration of increased visibility was related to the background wind that advected the environmental fog into the seeded area. The numerical model successfully reproduced the laboratory and field experiments’ results. The numerical model was used to analyze optimal seeding regimens and visibility sensitivity to the concentration, size, and salinity of the seeding drops, concentration of the fog droplets, the height of seeding, and other parameters.

Author Biographies

  • Mark Pinsky, The Hebrew University of Jerusalem

    Scientific researcher, developer of fog numerical model

  • Ehud Gavze, The Hebrew University of Jerusalem

    Dr. Ehud Gavze participated in all experiments and in the formulation of the numerical fog model

  • Ayala Ronen, The Israel Institute for Biological Research

    Dr. Ayala Ronen were responsible for experiments with the fog chamber

  • Smuel Elisha, The Israel Institute for Biological Research

    Measurements during the fog chamber experiment

  • Ofir Shoshanim, The Israel Institute for Biological Research

    Responsible for the field experiment

  • Pavel Khain, The Israel Meteorological Service

    Development of the fog forecast model


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Technical Notes and Correspondence

How to Cite

Warm Fog Elimination by Seeding with Salty Drops: Experiments and Theory. (2024). The Journal of Weather Modification, 55(1). https://doi.org/10.54782/skr2b986