農業気象
Online ISSN : 1881-0136
Print ISSN : 0021-8588
ISSN-L : 0021-8588
51 巻, 4 号
選択された号の論文の9件中1~9を表示しています
  • 本間 幸治, 青野 靖之, 小元 敬男
    1995 年 51 巻 4 号 p. 321-327
    発行日: 1995/12/10
    公開日: 2010/02/25
    ジャーナル フリー
    The relationship between temperature and the southern limits of temperate deciduous trees in Japan is discussed by using two indexes of temperature. One is the mean temperature of the warmest month to represent summer condition, and another is the chilling hours (accumulated hours below 7.2°C (45°F)) for winter. Eight species of deciduous trees (Zelkova serrata, Fagus crenata, Aesculus turbinata, Pterocarya rhoifolia, Betula ermanii, Quercus mongolica, Ulmus davidiana and Acer mono) were chosen for this purpose. It appeared that the chilling hours are effective in determining the southern limit of Zelkova serrata, suggesting at least thermal condition in winter is important in the warm side distribution for this species. For other species, the case in which winter condition may affect southern limits is found in the coastal areas and the relatively low latitude region of Japanese mainland.
    The impact of global warming on the potential probability of occurence for Fagus crenata in Osaka Prefecture and its vicinity is also examined. For a 1.5°C mean temperature rise, the potential probability becomes 0.02-0.21 from the present 0.13-0.68 in Mt. Izumi-Katsuragi and Mt. Koya area, and 0.24-0.70 from 0.65-0.76 in Mt. Kongo. For a 3.0°C rise, the probability decreases to 0.04-0.34 in Mt. Kongo. In the other two areas, it will become almost 0 suggesting the climatic condition becomes too warm for the occurence of this species.
  • 大和田 道雄, 石川 由紀, 中村 達博
    1995 年 51 巻 4 号 p. 329-334
    発行日: 1995/12/10
    公開日: 2010/02/25
    ジャーナル フリー
    We studied the characteristics of cold air drainage under a traveling anticyclone on west side slope of Kamikawa basin in Hokkaido in northern Japan for 7 days from 3 to 9 October 1994 using Takara thermistor double mode temperature printers (Print Multi D613, Takara Industrial Company). The results are summarized as follows.
    1) The spectral analysis of air temperature fluctuations showed three peaks at 85, 50-52, and about 10 minutes.
    2) The peak at 85min, was about 30min, longer than that observed before at Sugadaira basin in Central Japan.
    3) The differences in the peak period between Kamikawa and Sugadaira basins may reflect the difference in the cooling effect between the two basins.
  • 皆川 秀夫
    1995 年 51 巻 4 号 p. 335-343
    発行日: 1995/12/10
    公開日: 2010/02/25
    ジャーナル フリー
    27日齢の雌豚の型枠より, 石膏とプラスチックを用いて模型豚を作製した。2台の汎用カメラを用いた立体写真測量法により, 模型豚の表面積を測定し, その誤差を検討した。誤差は, 模型豚の3次元座標値を算出するときの光学系誤差と, 被写体の複雑な輪郭をとらえるときの形状誤差とからなる。光学系誤差は, 模型豚の周囲に配置した28個の基準点を用いて推定した。基準点は立体写真を用いて模型豚に貼付した約300個の指標の3次元座標値の計算に, 指標はその断面形状の把握および表面積の算出に, それぞれ用いた。形状誤差は, 模型豚に覆った方眼紙の1mm平方の眼の数を計測して求めた実測表面積と立体写真より算出した値とを比較し, 評価した。
    基準点におけるX軸座標およびY軸座標の誤差は1mm以内にあった。Z軸座標の誤差は3mm以内にはいった。これらの誤差は予測された範囲内にあった。これらの誤差より, 模型豚の胴体のある隣接断面部位における表面積の誤差は, その部位の形状を半径70mmと66mm, 傾斜長27mmの円錐台と仮定すると, 約5%となった。光学系誤差は表面積の有効数字を最少にすることで無視できる。
    立体写真より求めた模型豚の全表面積は, 実測値との差が34cm2となり, 相対誤差でもわずか1.2%となった。このことは, 形状誤差は僅少であり, 汎用カメラを用いた立体写真は精度が高いことを意味する。
  • 山田 一茂
    1995 年 51 巻 4 号 p. 345-354
    発行日: 1995/12/10
    公開日: 2010/02/25
    ジャーナル フリー
    Accuracy of spatial estimation of air temperatures can be very poor for a short term temperature. The objective of this paper is to study feasibility of the regional estimation of air temperatures with a nocturnal cooling model, which was proposed by Kondo & Mori (1982) to describe nocturnal cooling rate with wind speed and site-specific parameters.
    First, relationships between elevation and air temperatures within diurnal cycles were addressed at 27 monitoring points across a region of 110km×100km in central Japan. The weather data were obtained from the Automated Meteorological Data Acquisition System. The results showed that air temperature in the evenings was linearly related to the elevation above sea level with little perturbations from the weather, wind speed and topography. In contrast, minimum air temperature in the mornings and nocturnal cooling rate were greatly influenced by the above factors. Furthermore, in a complex terrain, the morning air temperature and cooling rate were unrelated to those at nearby points. Therefore, the two temperature traits may not be accurately estimated by using spatial interpolation.
    Second, two parameters (a & b) of the nocturnal cooling model were determined for each of the 27 monitoring points, and were ralated to topographical features of the points. Indexes of surface flatness (Sidx), cubical measure by a concavo-convex space (Cidx) and steepness (Ridx) on the level surface at observation were defined and calculated for each point using elevations of the grid points of the Digital National Land Information. The parameter b, which represents thermal conditions and accumulation of cold air, was related to Sidx and Cidx. The parameter a, which represents the extent of air mixing, was related to Ridx.
    The short-term air temperatures could therefore be estimated on a regional basis with the nocturnal cooling model, whose parameters are determined with the topographical indexes.
  • 山川 修治
    1995 年 51 巻 4 号 p. 355-361
    発行日: 1995/12/10
    公開日: 2010/02/25
    ジャーナル フリー
  • 施設園芸研究部会
    1995 年 51 巻 4 号 p. 363-364
    発行日: 1995/12/10
    公開日: 2010/02/25
    ジャーナル フリー
  • 局地気象研究部会
    1995 年 51 巻 4 号 p. 365-368
    発行日: 1995/12/10
    公開日: 2010/02/25
    ジャーナル フリー
  • 気候変化影響研究部会
    1995 年 51 巻 4 号 p. 369-370
    発行日: 1995/12/10
    公開日: 2010/02/25
    ジャーナル フリー
  • 耕地気象改善研究部会
    1995 年 51 巻 4 号 p. 371-375
    発行日: 1995/12/10
    公開日: 2010/02/25
    ジャーナル フリー
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