On the Geographical Distribution and the Daily Maximum Amount of Manchurian Rainfall

Abstract

1. According to the observation at about 40 stations in Manchuria, the average annual rainfall amount shows no more. than one half to one third of that in Nippon proper.
2. The geographical distribution of annual rainfall of the east mountainous region shows about 900mm. and gradually decreasing to the west and about 300mm. in the west of the Hingan range.
3. The distribution of rainfall in the middle plain region occurs chiefly on the rain due to mountain barriers towards the east by the southwest monscon in summer and is of comparatively rare occurrence by the rain due to cyclones.
4. The prevailing direction of rain-bearing wind occurs north in April, east-northeast in May, south-southwest in four months from June to September. The prevailing direction of the total amount of rainfall occurs west-southwest in April, east-north-east in May, south in summer four months. The average amount of rainfall divided by the number of wind direction occurs the maximum value east-northeast in April, southwest in May, south-southeast in summer four months.
5. The daily maximum amount of rainfall observed 209.3mm. at Yingkou in the south, 157.0mm. at Anta in the north. In the south the daily maximum amount of rainfall is decreasing accordingly to the distance from the coast. In the north there are heavy rainfall region about 150mm. daily in the valleys of the rivers Nonni and Sungari. Another places measured the daily amount under 200mm. in the south and 100mm. in the north.
6. In the south the maximum daily amount of rainfall caused by the rain due to the typhoon cyclone and in the north by the rain due to the ascending current depression with local thunderstorm.
7. The percentage the daily maximum amount divided by the average annual total rainfall the larger places are over 30, the average is about 20, the smallest is 13.