In this paper, the author intends to depict the detailed distribution of surface winds over Kinki District and the eastern parts of Chugoku and Shikoku District, that is affected by pressure patterns on a synoptic scale. Available data to delineate the detailed map of surface wind at optional times are so sparse that the data of climatological stations, where observations are made only at 9 a.m., were mainly used in this study. One hundred sheets of daily maps of stream-lines of surface winds were drawn, using the data of some 260 Stations in this region.
When gradient wind is weak, local circulations, such as land- and sea-breezes and mountain- and valley-winds, resulting from the diurnal change of thermal condition, prevails on the whole area of this study. When the speed of gradient wind exceeds 10 m / s, such a case is excluded. The gradient flow pattern over this area, corresponding to the distribution of surface wind systems, was classified into 6 types, as shown in Table 1. Type A, Type B and Type C almost occur in the winter season, associated with the winter monsoon. The other types mainly appear in the warm season. Type D occurs when Kinki District and its surroundings lies in the warm sector of a cyclone, which advances in the northern parts of Japan Sea, or on the southern side of a front which runs from east to west. Type E appears when this area is situated in the rearside of a migratory anticyclone or ahead of a typhoon. On the other hand, Type F arises under an influence of the passage of a typhoon or an extratropical cyclone.
Data of wind for these types were arranged into the windrose, related to each of the flow patterns, for each of the climatological stations. Then the author attempted to depict the climatic representation of the detailed distribution of surface wind. From the arrange-ment of the above-mentioned data, the prevailing wind direction for each station is defined as follows.
1. The prevailing wind direction of a station is not discernible as a rule when the frequency of calm exceeds 50 percent of the total in each flow pattern.
2. The prevailing wind direction can easily be decided when a flow from a single direction exceeds 60 percent or more of the total frequency of each flow pattern.
3. In cases when the frequency of a single direction is less than 60 percent of the total, if the frequency exceeds 60' percent of the total by adding the prevailing frequency to a neighbouring one, the prevailing wind direction can be determined by computing the vector mean of them.
4. In other cases, the prevailing wind direction is not discernible. However, when a station is situated in the convergence zone formed between local wind systems, the pre-vailing wind direction can be decided by the direction of gradient of frequency, even if it does not exceed 60 percent of the total.
Maps of the detailed distribution of surface winds were delineated as shown in Figs. 2, 3, 4, 5, 6 and 7. Streamlines were drawn on the basis of prevailing winds at each station. Broken lines indicate the condition of wind in an area, where either wind is always light or determination of prevailing wind is difficult to ascertain due to the scarcity of stations and their locations at valley bottoms in mountainous regions. Fan and solid arrows on the upper parts of these maps indicate flow patterns.
Results show the characteristic features of the distribution of local wind systems in this region. The pattern of local wind systems and the distribution of wind speed changed with the synoptic conditions, especially the pressure patterns, and are affected by major topography, though the height of mountains is much lower than that of Central Japan. The area of strong wind mainly tends to be found along the sea coast and rivers on open plains and valleys in mountainous areas. On the other hand, areas with calm or light winds distribute in the shadow regions of mountain ranges.

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This paper reviews Japanese and alien studies during the past decade, of coastal cliff recession and its related phenomena such as (1) wave-cut platform formation and its defor-mation, (2) abrasion platform development and (3) the process of continental shelf formation having erosional origin, and points out basic, important problems involved in these studies from the viewpoint of rock control theory.
The review of the cliff erosion studies refers to recent measuring techniques, field investigations and laboratory experiments; it emphasizes (1) usefulness of aerial photo-graphs in collecting precise data of recession and (2) significance of wave tank experi-ments especially in clarifying basic relation involved in the erosional process. In a sum-mary of the studies of wave-cut platform, they are classified into the two: one is the studies discussing the mechanism of horizontal development in the field or laboratory, and the other the process of vertical deformation of platform surface in the field. Concerning the development of actual abrasion platform, the following topics are mentioned: (1) critical water depth for submarine bedrock erosion, (2) rate of abrasion of shallow water bedrocks, and (3) horizontal growth of abrasion platform. The last section of this paper focuses on a model of continental shelf formation, which was framed up by considering a combination of cliff recession and the postglacial transgression.

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Geographical distribution and time variation of atmospheric carbon-dioxide in and around Tokyo were investigated. The instrument used in this survey is an ASSA-1 infrared analyzer (0_??_1000 ppm, CO₂). The sampling and analyzing systems are illustrated in Fig. 1. Special attentions are taken to eliminate dust and water vapor in the atmosphere by use of a precipitation bottle and a hand-made condenser.
Geographical distributions of CO₂ are shown in Fig. 2. Fig. 2-A shows the change of CO₂ off coast of Tokyo, and Figs. 2-B and C are the distributions in and around Tokyo. The influence of CO₂ originated from Tokyo and its vicinity extends more than 100km.
Several examples of the diurnal variation of CO₂ at Rissyo University (Shinagawa-ku, Tokyo) are shown in Fig. 3. Daily maximum concentration of CO₂ usually exceeds 500ppm and sometimes it reaches about 660ppm. These extreme values are observed under a calm and inversion condition, particularly in the colder seasons.
In Fig. 4, the seasonal variation of CO₂ at Rissyo University, both monthly mean value (circle) and monthly range, is illustrated. The concentration reaches its minimum in summer when combustion of fuel is less than other seasons and photosynthesis of plant is more active. The maximum value is observed in winter, and the extreme maximum is observed under a calm and inversion condition. The winter minimum does not differ largely from that in summer, because strong winter monsoon eliminates high concentration. The annual mean value during 1972_??_1973 is about 350ppm, which exceeds the world average by 25ppm.

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In Central Japan, orographically and thermally induced anticyclones, cyclones and fronts appear very frequently in winter. Takayama High is one of such local anticyclones, which is formed either thermally on clear nights by long wave radiation or mechanically by upper winds. In the latter cases, it usually accompanies Matsumoto Low simultaneously. In the thermal cases, cold air cooled by radiation in the mountaineous region flows down along large valleys and produces local discontinuity lines on the Hokuriku coasts of the Sea of Japan and on the southern coast of Boso Peninsular. On this account, the Takayama High has been studied mainly in relation to the Hokuriku Front, which brings heavy snowfalls in the Hokuriku region. A local cyclone, Suruga-wan Low, is frequently formed when the winter monsoon becomes weaker. The previous studies made it clear that a winter maximum and a summer minimum of its appearance are caused by the thermal effects of water and air temperatures of the Suruga Bay and its vicinity. It has already been stated that the origins of the local front, Boso Front, are closely related to (1) the local high in thermal cases and (2) the convergence of two or more currents branched off topographically from the same Pc air mass with a local cyclone on the Sagami Bay or the Suruga Bay.
The purpose of this paper is to clarify their synoptic climatological features. The results are as follows;
i) On the meso-scale charts, the occurrence of the Takayama High is 12.3 days per month on an average from December to February, the Suruga-wan Low 9.8 days and the Boso Front 21.3 days. The frequencies of occurrence of the Takayama. High are found most frequently in December, but those of the Suruga-wan Low are in Febuary and the Boso Front in January. This is accounted for by the fact that each of them corresponds with different synoptic pressure patterns.
ii) Most frequently the Takayama High persists for 18—20 hours, forming at 17—19^h and disappearing at 10—12^h on the next day.
The shape of the Takayama High is influenced by the direction of upper winds (Fig. 1 (a) (b)) and the differences of the pressure gradient from the center have a close relation to the differences of the direction. In general, it is very difficult to define the size of a local anticyclone, but if the Takayama High is defined by the outermost closed isobar, the areas of the Takayama High of the W—SW type are about 3 times as large as the one of the NW type (Fig. 2 and 4). The maximum of the area of W—SW type Takayama High is 39.1×10³km², and the one of NW type is 9.1×10³km².
iii) In the case of the Takayama High of the W—SW type, a local cyclone is formed from time to time in the Matsumoto district by orographical effects. When a Matsumoto Low is formed, strong southerly wind blows and air temperature becomes higher in the district. An indicator of the relative intensity of the Matsumoto Low, ΔP (the difference of sea level pressure at Takayama minus Matsumoto) is obviously related to the W—SW upper wind (mainly 850—700mb); The stronger the wind of these levels is, the greater ΔP occurs simultaneously (Fig. 5). Furthermore, ΔP is related clearly to the temperture of these levels, when 700mb temperature is above -13°C.
It seems that warm strong wind, whichh is observed in association with the Matsumoto Low, is caused by a föhn effect. This is verified by facts that ΔT (the difference of air temperature at Matsumoto minus its vicinity) has a relation to the temperature of the height of the mountain-tops (about 700mb) (Fig. 9) and to the wind direction of the levels, and also by the distributions of air temperature, wind (Fig. 8) and relative humidity at the surface level.

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