著者

小河原 洋平 田浦 扶充子 島谷 幸宏

出版者

土木学会

雑誌

水工学論文集 Annual journal of Hydraulic Engineering, JSCE (ISSN:18808751)

巻号頁・発行日

vol.63, pp.I_355-360, 2018

著者

高 裕也 二宮 順一 森 信人

出版者

土木学会 = Japan Society of Civil Engineers

雑誌

土木学会論文集B1(水工学) (ISSN:18808751)

巻号頁・発行日

vol.74, no.4, pp.I_175-I_180, 2018

被引用文献数

2

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現在気候実験3,000年(60年×50メンバ)および将来気候実験5,400年(60年×90メンバ)の大規模アンサンブル気候予測データ(d4PDF)を用いて,日本海沿岸における低頻度気象災害要因の一つである爆弾低気圧に対する気候変動の影響評価を実施した.現在気候および将来気候からの爆弾低気圧抽出結果から,発生個数にはほとんど将来変化はないが,最低中心気圧の強度は将来的に増加する傾向があることがわかった.また,日本沿岸域に被害を及ぼす可能性がある爆弾低気圧について解析した結果,全体に占める台風並みに発達する爆弾低気圧の割合が増加し,特に中心気圧の強度も増加する傾向を示した.

著者

市山 誠 石川 忠晴

出版者

公益社団法人 土木学会

雑誌

土木学会論文集B1(水工学) (ISSN:18808751)

巻号頁・発行日

vol.70, no.4, pp.I_727-I_732, 2014

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This study investigated the basic hydraulic characteristics of a bending river section with a cut-off channel by flume experiment. Contents of measurements included the longitudinal profile of water surface, flow velocity in cross sections by an electromagnetic current meter, and the surface flow velocity by using PIV methods. In addition, tendency of bed sediment motion was observed by bottom tracer experiment. Installation of cut-off channel resulted in a wide dead water area at the side of divergence in the main stream and low-velocity area at the center of the confluence. The point of surface flow which attacked the bank moved upstream in the main stream of distribution. Then the secondary flow became stronger, and the direction of bottom flow was strongly skewed in a transverse direction. Moreover, the bottom tracers moved and accumulated rapidly from the outer bank towards the inner bank at the curve of distributaries downstream. It suggested the occurrence of scour and sedimentation.

著者

瀬戸 心太 田口 諒

出版者

公益社団法人 土木学会

雑誌

土木学会論文集B1(水工学) (ISSN:18808751)

巻号頁・発行日

vol.72, no.4, pp.I_223-I_228, 2016

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 Japan Meteorological Agency announces emergency warning of heavy rainfall when 48-hour rainfall amount is expected to exceed the 50-year value at more than fifty 5km-grids. Spatial distribution of heavy rainfall is important to judge the emergency warning. In this study, by using the GSMaP data from 2001 to 2009, 50-year value of 48-hour rainfall amount is calculated all over Japan and the surrounding ocean. As the number of available GSMaP data is limited and GSMaP may be affected by surface snow cover, the calculation method needs to be modified. 48-hour rainfall amount exceeded to its 50-year value on prefecture scale at two heavy rainfall events which are said to be corresponding to the emergency warning. It is important to check the spatial scale of grids with high return period rather than the absolute value of return period. This method is applied for Kanto and Tohoku heavy rainfall in September 2015.