雨氷発生日数の地域分布に関する統計的解析

DOI Web Site 被引用文献4件 参考文献38件

書誌事項

タイトル別名
  • Statistical analysis on the areal distribution of annual number of days with glaze.
  • ウヒョウ ハッセイ ニッスウ ノ チイキ ブンプ ニ カンスル トウケイテキ カイセキ

この論文をさがす

抄録

To examine the climatological features of glaze occurrence, in Nagano prefecture, where there have been many reports on the glaze, glaze occurrence days were defined and their areal distribution was statistically analyzed.<BR>Glaze forms on exposed objects at the ground by the freezing of supercooled water droplets, in a kind of ice accretion. For glaze to occur, in general, two meteorological conditions must be satisfied. One is the existence of a warm air layer (air temperature above 0°C) in the upper air, for melting of dry snowflakes into rain drops; the other is the existence of a cold air layer (air temperature below 0°C) near the ground, for cooling of rain drops into supercooled water droplets. This is called a “melting ice process”. Although glaze also occurs at air temperatures below 0°C at all levels (no warm air layer), in what is called a “supercooled warm rain process”, only the term “melting ice process” is used in this study.<BR>Aerological data were used to examine the warm air layer in the upper air, AMeDAS data were used to examine the cold air layer near the ground and precipitation, during 20 winter seasons (November 1979-April 1999). A day that satisfied these two meteorological conditions is defined as a glaze occurrence day. As a result, there are frequent peaks of glaze occurrence in December and March. The number of days with glaze has been decreasing in the past 6 years.<BR>Next, a mesh map of annual mean number of days with glaze was obtained by multiple regression analysis using a factors that represent a topographical features as independent variables. The mesh map shows a high number of days with glaze in central and eastern Nagano prefecture. In particular, because of the close relationship between the annual mean number of days with glaze and the altitude, a high number of days with glaze were estimated to occur mountain areas and highlands, while a low number of days with glaze occurred in low altitude areas of northern and southern Nagano prefecture.

収録刊行物

  • 雪氷

    雪氷 62 (4), 355-365, 2000

    公益社団法人 日本雪氷学会

被引用文献 (4)*注記

もっと見る

参考文献 (38)*注記

もっと見る

キーワード

詳細情報 詳細情報について

問題の指摘

ページトップへ