Some effects of cloud turbulence on water-ice and ice-ice collisions

M. B. Pinsky, A. P. Khain

Research output: Contribution to journalArticlepeer-review

52 Scopus citations


Formation of relative velocities between low-density ice particles and the surrounding air within a turbulent medium is analyzed. Turbulence is assumed to be homogeneous and isotropic. Both the inertial and viscous turbulent ranges are taken into account when describing the turbulent flow characteristics. It is shown that the inertia of drops and ice particles falling within a turbulent flow leads to the formation of a significant relative velocity between particles, which can be greater (especially for those with small sedimentation velocity) than gravity-driven velocity difference. It is also shown that for ice particles, the turbulence effects related to particles' inertia are much more pronounced than for water drops. An increase in relative velocity between particles leads to an increase in the swept volume and the collision kernel. As a result, a marked increase in the rates of riming and ice-ice interactions is expected.

Original languageAmerican English
Pages (from-to)69-86
Number of pages18
JournalAtmospheric Research
StatePublished - Jun 1998

Bibliographical note

Funding Information:
This study was partially supported by the Germany-Israel Science Foundation (grant 0407-008.08/95), the Israel Science Foundation founded by the Israel Academy of Sciences and Humidities (grant 572/97) and the Lady Davis Foundation of the Hebrew University of Jerusalem.


Dive into the research topics of 'Some effects of cloud turbulence on water-ice and ice-ice collisions'. Together they form a unique fingerprint.

Cite this