This study clarifies the vertical structure of diurnal variation in local wind systems, including sea breezes over the Kanto region, by focusing on temporal changes in the wind system structure caused by large-scale sea-breeze development. Because direct observation of the atmosphere's vertical motion is difficult, we developed an alternative index in which the quantity of divergence is calculated using observed surface wind data. However, observed surface wind data are inappropriate for calculating divergence fields because of differences in the observation heights of wind at different stations. Therefore, a roughness parameter corresponding to the wind direction at each observation point is estimated from land utilization data around the observation points based on the empirical formula proposed by Kuwagata and Kondo (1990). The adjustment of wind velocity is based on the logarithmic law of wind velocity. After adjustment, the wind velocity in the area near Tokyo Bay and absolute values of the quantity of divergence increased.
Typical sea-breeze days were selected, and temporal changes in the characteristics of the average wind and divergence fields were examined. Next, correlation coefficients of the quantity of divergence were calculated between marked divergence areas and each grid point in the study area. This analysis was performed to understand the relationship between the divergence and convergence areas and to identify areas where the diurnal variation in the divergence value is equal to that of marked divergence areas. At 09:00, a divergence area formed in Tokyo Bay (area TB), and sea-breeze circulation was observed between area TB and the convergence area in the neighborhood of Tokyo. At 11:00, with sea-breeze development, the influence of the Sagami Bay sea breeze in area TB weakened the correlation with the convergence area of Tokyo. Conversely, a valley wind developed in North Kanto, and valley wind circulation was observed between the divergence area around the prefectural border between Gunma and Saitama (area GS) and the convergence area of a neighboring mountainous district. It appears that typical valley wind circulation developed on a comparatively small scale; moreover, at that time, the valley wind circulation of North Kanto appeared to be independent of the seabreeze circulation of South Kanto. After midday, the original correlation level with area TB was observed in the area between Kanagawa and Sagami Bay, which suggested a switch from the typical sea-breeze circulation to a large-scale sea breeze. With this large-scale sea-breeze development, the valley wind circulation in North Kanto became indistinct. Simultaneously, area TB developed a negative correlation with area GS. When the large-scale sea-breeze development was marked, the divergence in area GS corresponding to valley wind circulation weakened.

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In the western part of the Kofu Basin, embankments often called Shingen-tsutsumi are distributed around the confluence of the Kamanashi River and the Midai River. Although there has been a great deal of historial research on Shingen-tsutsumi, few attempts have been made to clarify their concrete roles based on natural sciences. Therefore, this paper reevaluates the flood control system of Shingen-tsutsumi based on inundation flow simulations.
We arranged each embankment (Ishitsumidashi, Shirane-Shogigashira, Tatsuoka-Shogigashira, Horikiri, Ryuo banks, and Kasumi embankments) on an old digital elevation model (DEM) produced by smoothing the present DEM. Then, we performed inundation flow simulations using a dynamic wave model to calculate the expanse of the Midai River using each old DEM. In these simulations, we reproduced the previous flows of the Midai River, and evaluated the flood control ability of each Shingen-tsutsumi embankment. We concluded that the flood control system of Shingen-tsutsumi would not have been effective if the Ishitsumidashi, Shirane-Shogigashira, Horikiri, Takaiwa, and Ryuo embankments had not been arranged in this order. We therefore speculated that these embankments were constructed before the modern age within a short period. This finding differs from historical studies of Shingen-tsutsumi.

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This study aims to identify retail agglomeration places in Tokyo prefecture from NTT Townpage Database (TPDB) by applying spatial clustering and to analyse their size, functional structure, and distribution using GIS. Eleven retail and service functions necessary in daily life are analysed, which consist of 164 types of shop and service facilities in TPDB. There were about 250,000 shops (including service facilities) in Tokyo prefecture as of March 2007.
The distances between shops are measured using longitude and latitude data in TPDB. A program is constructed to delimit retail agglomeration places in terms of spatial contiguity and agglomeration volume. Shops are considered to be contiguous when the distance between them is less than spatial search distance of 50 m. Retail agglomeration places are then identified when their agglomeration volume is greater than or equal to the threshold of 20 shops. The number of retail agglomeration places identified by assuming these two parameters totals 1,143.
Retail agglomeration places are classified into five hierarchical levels on the basis of size. The highest level consists of 10 shopping streets including the Ginza. The number of shopping streets at the high level is 13, at the upper level 46, at the middle level 269 (including 10 shop clusters, i.e., commercial buildings), and at the low level 805 (including 130 shop clusters).
It is found that 125 types of shop are located restrictedly in one of hierarchical levels. Thirty-two types are located restrictedly in the highest level of retail agglomeration places. Therefore they are referred to as the highest order of retail function. On the other hand, 28 types of retail function are considered to be high order, 11 types upper order, nine types middle order, and 45 types low order. It is also found that 39 types of shop are not located restrictedly in one of hierarchical levels but are located in all hierarchical levels. They may be referred to as the footloose type and comprise 40% to 45% of the total at all levels of retail agglomeration places.
Two types of shopping cluster are identified at the low level. One has nearly same composition ratio of the highest-order function as retail agglomeration places at the highest level. The other has a high composition ratio for the low-order function. As the result that the location patterns were analysed for retail agglomeration places in the 23 wards of Tokyo and Tama area, the places at the highest, high, and upper levels show a dispersed pattern and those at the low level show an agglomerated pattern.
This study also tries to represent the supply geography in Toshima ward as a sample study area. There are 39 retail agglomeration places in Toshima ward. There is one shopping street at the high level, four at the upper level, 10 at the middle level, and 24 at the low level including six shop clusters.

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Centripetal population movements in the Tokyo metropolitan area and changes in the supply of condominiums since the latter half of the 1990s have been reported. Hence, this study aimed to clarify the demographics of the residents of those condominiums and to examine changes in housing acquisitions in recent years. An analysis of questionnaires administered to residents revealed various family types, including not only small family units such as singles and “double-income, no kids” partners, but also families with small children, who were believed typically to move to the suburbs, and older families who had moved away from the suburbs. Each family type had reasons unique to the life stage in which they moved; however, commonalities in behavior to minimize social risk can be inferred. The opportunities to obtain suitable housing become similar to ascending the career ladder in this era when employment and income stability have decreased.

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This study aims to clarify how and why two different techniques of kombu (edible kelp) aquaculture were introduced in Minamikayabe, Hakodate city, at its geographical conditions.
Because of the loss of territory in Japan after the Second World War, kombu processors requested for the redevelopment of domestic production centers and began to import kombu from China, Korea, and Russia in the 1960s. Minamikayabe, a well-known production center of natural kombu, faced some difficulties such as the instability of “natural” kombu resources. Consequently, fishermen in this area took up kombu aquaculture, an alternative to the traditional natural kombu production. In 1966, the Kakkumi Fisheries Cooperative began focusing on intensive kombu aquaculture as a part of the pilot program of the Hokkaido Development Bureau. This project successfully implemented intensive kombu aquaculture in this region. An additional benefit of this project was that cultured kombu takes one year to mature, while natural kombu takes two. Subsequently, kombu aquaculture spreaded in other fisheries cooperatives, and Minamikayabe became the largest producer of kombu in Japan. In addition to intensively cultured kombu, the biennial cultured kombu, which can be harvested only after two years, is cultivated in this region.
Among the six fishing districts in Minamikayabe, the choice of two techniques of kombu aquaculture differed in Osatsube and Ofune. This choice was partly influenced by hamakakusa, a traditional practice followed in kombu trading, in which the prices of kombu are ranked according to differences in the quality of kombu by district, and which is applied to both natural and biennial cultured kombu. For example, in Osatsube, which has a higher rank under hamakakusa, a certain amount of biennial cultured kombu is continually cultivated. On the other hand, in Ofune, a district with a lower rank, only intensive culture is practiced, because intensively cultured kombu takes less time to mature compared with natural kombu. Thus, in Ofune, the quality of kombu was commensurate with the effort put into production. However, the prices of intensively cultured kombu are not influenced by hamakakusa.
The introduction of kombu aquaculture in Minamikayabe enabled fishermen to select either of the two techniques of kombu aquaculture while considering hamakakusa and thereby decreased regional economic disparities.

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