The Effect of Coalescence and Condensation on Rain Formation in a Cloud of Finite Vertical Extent

Abstract

The simultaneous effects of collisions between water droplets and their growth by condensation are investigated numerically for a cloud of finite vertical extent. The consequent changes in droplet distribution have been followed for time up to ∼15 min. A comparison is made between geometric collision efficiency and the collision efficiency of Shafrir and Neiburger. It is shown that the omission of growth by condensation may lead to considerable errors. Abstract The simultaneous effects of collisions between water droplets and their growth by condensation are investigated numerically for a cloud of finite vertical extent. The consequent changes in droplet distribution have been followed for time up to ∼15 min. A comparison is made between geometric collision efficiency and the collision efficiency of Shafrir and Neiburger. It is shown that the omission of growth by condensation may lead to considerable errors.