地理学評論
Online ISSN : 2185-1719
Print ISSN : 0016-7444
ISSN-L : 0016-7444
48 巻, 6 号
選択された号の論文の7件中1~7を表示しています
  • 河村 武
    1975 年 48 巻 6 号 p. 387-394
    発行日: 1975/06/01
    公開日: 2008/12/24
    ジャーナル フリー
    近畿地方および中国・四国地方東部について,地上風系の詳しい分布と総観的な気象条件との関連を調べた.一般風が強い場合には,第1表に区分した傾度風向の範囲に対応して,第2図から第7図に示した固有の地上風系の分布が見られる.この地域は前に同様の方法で明らかにした中部日本と比べて山地の高度がかなり低いにもかかわらず,やはりかなり規模の大きい地形の影響と見られる局地風系が存在し,風道となるところに強風域(第8図),山地の蔭になるところに弱風域(第9図)が出現することがわかった.
  • 砂村 継夫
    1975 年 48 巻 6 号 p. 395-411
    発行日: 1975/06/01
    公開日: 2008/12/24
    ジャーナル フリー
    海蝕崖の後退とそれに関連した諸現象-波蝕棚の形成・発達と変形,海蝕台の発達および侵蝕性起源の大陸棚の発達-についての最近10年間の内外の研究から得られた新たな知識をまとめ, rock controlの立場から問題点を指摘した.
  • 新井 正, 高山 茂美, 高村 弘毅, 関根 清, 立石 由巳, 小林 徹, 庄田 正宏
    1975 年 48 巻 6 号 p. 412-417
    発行日: 1975/06/01
    公開日: 2008/12/24
    ジャーナル フリー
    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.
  • 杉村 暢二
    1975 年 48 巻 6 号 p. 418-423
    発行日: 1975/06/01
    公開日: 2008/12/24
    ジャーナル フリー
  • 野元 世紀
    1975 年 48 巻 6 号 p. 424-437
    発行日: 1975/06/01
    公開日: 2008/12/24
    ジャーナル フリー
    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—19h and disappearing at 10—12h 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.
  • 1975 年 48 巻 6 号 p. 438-444_3
    発行日: 1975/06/01
    公開日: 2008/12/24
    ジャーナル フリー
  • 1975 年 48 巻 6 号 p. e1
    発行日: 1975年
    公開日: 2008/12/24
    ジャーナル フリー
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