ON THE GRAVITATIONAL COALESCENCE GROWTH OF THE CLOUD DROPLETS IN A CLOUD WITH FLUCTUATING WATER CONTENT

<正> Ⅰ. The Problem As a result of observation made during the past one or two decades the broad structure of the drop-spectra in a cloud is now more or less clear. However, the interpretation of these spectra is still subject to difficulties in several important respects. As pointed out by the first author, the present theories of cloud droplets growth are not so satisfactory. Above all, the growth rate of the droplets under condensational or gravitational coalescence is rather small for droplets of radius of 10—30μ. Some of these theories seem to be able to give us some interesting results, but, to our regret,