Abstract
Monsoon snowfalls at the coastal stations of the Japan Sea have been examined. It is found that the amount of precipitation sorely due to monsoon becomes a maximum when the minimum of pressure wave from a continental high arrives at the station.
The author tried the following explanation of this remarkable fact. The monsoon cloud is formed by a grand thermal convection. The longer the air stays over the surface of the warm sea the more thicker the cloud becomes. A simple estimation shows that the time of lying of the damp air over the sea is maximum which arrives at the station just at the time of minimum of pressure oscillation.
