The purpose of this paper is to clarify the local distribution of convective echoes and its relation to topography in the Tohoku district, during the midsummer-type pressure pattern. Using the data of radar at Sendai meteorological observatory and Akita meteorological observatory, the author statistically investigated the distribution of convective echoes.
The results are summarized as follows;
1) Without consideration of diurnal variation, the appearances of echos increases in number in proportion to altitude as far as 1, 400m.
2) The number of appearance is large on the east side of mountains, but it is small on the eastern part of basins and plains.
3) The number of appearance reaches the maximum at 15:00 under unstable conditions, and at 18:00 under stable conditions.
4) Distributions of echos are also influenced by an angle formed by mountains and upper wind direction. For example, when atmosphere is unstable, the number of appearance is the largest on the leeward of high mountains which are parallel to wind direction (700mb).

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It is one of the objectives of transport geography to describe the historical evolution of transport modes. In this paper the author investigated the process of spatial diffusion of motorcars in Kyushu, Southwestern Japan, during the Taisho and the pre-war Showa eras (1912-1936) using an analytical framework of geographical diffusion theories. Because motorcars were introduced into Japan as one of modern transport facilities by which traditional transport facilities were driven away, we may regard motorcars in those days as an innovation of the road traffic.
The propagation rate, motorcars per ten thousand population, was calculated for each of seventy-seven areas (administrative districts, gun) for each year. Subsequently the distribution pattern of such propagation rates for every year of the time period was simplified through the T-mode factor analysis. These results were mapped and interpreted (Fig. 5). Next, a logistic function which is frequently used to describe some growthh curve, was applied to the change of the propagation rates by each area. The year at which the diffusion originated in a given area and the parameter b from the logistic function Y=K(1+me^-bt)^-1 (where Y is the propagation rate at time t) were specified. The variation of each of these two elements was examined by means of regression analyses.
In the early Taisho era the twenty-two areas with a high standard of propagation rate were mainly distributed through Fukuoka and Saga Prefectures in the northern Kyushu. On the other hand, few such areas existed in the central and southern Kyushu, except for only several areas where the local cities, i. e., Kumamoto, Peppu, Miyazaki and Kagoshima were located. Thereafter those areas with a high standard propagation rate increased in number and in the early Showa era there were thirty-five such areas. The major part of the central and southern Kyushu, and islands such as Tsushima, Iki, Kumage and Oshima remained lower in the propagation rate throughout the time considered.
The years when the diffusion originated differed in areas. In the four areas with local cities, Fukuoka, Omuta, Kumamoto and Kagoshima the diffusion dated from the first year of Taisho (1912), while in the two areas of the southern Kyushu it dated latest from the first year of Showa (1925). These differences were due to factors in equation (2), which indicates that the motorcars were introduced earlier into those areas where there were larger urban settlements, and which were closer to the cities from which the motorcars were originally introduced. The parameter b from the logistic function, an estimate of the propagative speed, also differed in areas. The regression equation (3) confirms that the later the year at which the diffusion originated was, the higher became the propagative speed of motorcars.

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[in Japanese]

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In the Shonai Plain, northeastern Honshu, the strong easterlies and the NW winter monsoon prevail. The strong easterlies which blow along the Mogami River are particularly called “Kiyokawa-Dashi”.
In order to make clear the detailed distributions of such strong local winds, the author investigated the wind-shaped trees. The wind-shaped trees observed were: Betula platyphylla, Ginkgo biloba, Populus nigra var Italica, Prunus sp., and Cryptomeria japonica.
The results are summarized as follows:
1. According to some characteristics of deformation of the tree, it is considered that the deciduous trees mentioned above have been deformed by the strong easterlies and cryptomeria japonica deformed by the NW monsoon (Table 1).
2. The strong easterlies blow along the valleys coming into the plain. In general, these winds, it begins blowing at the inside of each valley, where is a little upper side near the valley mouth (Fig. 2).
3. In southern part of the plain along the Aka River, the strong southerlies are recognized. It may be considered that the southerlies have no relation to the “Kiyokawa-Dashi” winds (Fig. 2).
4. The NW monsoon do not blow into the valleys coming into the plain. It may be considered that the Dewa Mountains which is situated on the eastern margin of the plain blocks an intrusion of the NW monsoon. At the inside of the Mogami River valley, however, some wind-shaped trees of Cryptomeria japonica are observable. This fact shows that the NW monsoon exceptionally blow into a large valley as the wind direction agrees with a valley strike (Fig. 3).

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[in Japanese]

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