Numerical Simulation of Effects of Cloud Top Temperatures and Generating Cells on Secondary Ice Production in Stratiform Clouds with a Detailed Microphysical Model

摘要

This paper outlines a one-dimensional, heightdependent bin model with detailed microphysical processes in which ice splinters are produced by a riming process. The model is then applied to simulate the shift of particle size distribution effected by the secondary ice production process within clouds with different generating cells and cloud top temperatures. The result of model simulations reveals the general effects of cloud updrafts on increasing ice particle concentration by extending the residence time of ice particles in clouds and providing sufficiently large supercooled water droplets. The rimesplintering mechanism is more effective in clouds with lower ice seeding rates than those with higher rates. Evolutions of hydrometeor size distribution triggered by the rime-splintering mechanism indicate that the interaction between large ice particles and supercooled water drops adds a “second maximum” to the primary ice spectra.