On the Theory of Cloud-formation in the Winter Monsoon Field

[摘要] In winter, frequently we observe the developed monsoon wind blowing over the sea from the cold continents. And it is a well noted phenomenon that the cloud layer which is formed in the monsoon field increases its thickness both to the upper and lower sides as the distance from the seashore of Siberia increases.The present auther wished to explain the following problems:1. The clouds are at first formed at the moderate height of the sky, at _??_ome distance from seashore, 2. The thickness of cloud layer increases both to the upper and lower sides as the distance from seashore increases, from the consideration that:- as the continental airmass moves on the sea being supplied much heat and water vapour it becomes gradually unstable and a thermal convection takes place and the clouds are formed.As to the process of monsoon the present author assumes some suitable conditions. And, by some fundamental equations of eddy-diffusion and of the evaporation formula (Dalton's), the distributions of temperature and water vapour are calculated and are shown in the graphic representation (fig. 2). In these discussions, the radiative transfer of heat is neglected because of its small quantity.And combining these two distributions, the present author shows in fig. 3 the distribution of relative humidity in the monsoon field, which will be said to give a fairly well explanation of the mechanism of cloud-formation in the field In addition the author makes some discussions about the instability of monsoon field and so on.

[学科分类] 大气科学