In the northern part of Japan, we sometimes have a summer with occasional days of abnormally low atmospheric temperature and experience serious failures of the rice-crops after such a season. In this paper, we have investigated the relation between the climatic conditions of abnormally cold summer and the local damage distributions of rice-crops in Hokkaido. Weather conditions of abnormally cool summer in Hokkaido were divided into the following four types, (1) dry cool summer, (2) wet cool summer, (3) combination type (summer with scanty rain and sunshine) and (4) miscellaneous type. Comparing the four weather types with the damage to the rice-crops, we have found that serious failures were experienced after summers of (2) and (3) type, especially the former, and also that a dry cool summer was usually followed by only a slight damage in that district.
In Kwanto district, when the wind is northeasterly, rain or cloudy weather is often experienced though there is neither low nor front in the synoptic chart. In the present paper the phenomenon is studied by using model distribution of atmospheric pressure and temperature. It is assumed that the coast line runs from west to east and turns to northeast in the neighbourhood of Idu-Oosima. The atmospheric pressure is high in the north and low in the south, and the temperature is low on the inland side and high on the ocean side, the temperature gradient is exceptionally great in the region having a breadth of about 100km along the coast line. The lines of equal estimated atmospheric pressure of upper layers, 200, 500, 1000 and 2000m above sea level, are shown in Figs. 2, 3, 4 and 5. The low pressure or the tendency of convergence of air current is seen in Figs. 2, 3 and 4. But at 2000m level no more convergence is seen in Fig. 5.