@article{oai:oacis.repo.nii.ac.jp:00001794,
 author = {山﨑, 恵市 and 北出, 裕二郎 and 井桁, 庸介 and 渡邊, 達郎 and 千手, 智晴 and 山田, 東也 and 大慶, 則之 and 池田, 怜},
 issue = {6},
 journal = {海の研究, Oceanography in Japan},
 month = {Nov},
 note = {能登半島北東端沖の3 点の海底に設置したADCPにより得られた流速記録を解析し，2007年10月8日に日本海海上を通過した低気圧により励起された近慣性内部波の特徴を調べた。観測された近慣性内部波は大陸斜面域では20～60 m深で鉛直的にほぼ同位相であったが，その振幅は表層よりも中層（38～58 m深）で大きかった。このような特徴を持つ近慣性内部波の形成機構を，実際の地形と風応力を用いた数値実験により調べた結果，沖合表層に励起された近慣性内部波が沿岸域へ達した後に半島東部の浅瀬域で散乱することと，その散乱波がほぼ同時に励起されて観測海域で干渉することが判明した。さらに，散乱波の干渉に寄与する海底地形の効果を調べるために能登半島周辺の浅瀬域を除外した検証実験を行った。その結果，近慣性内部波の中層での増幅には能登半島東部の陸棚域からの散乱波が重要な役割を果たし，鉛直的に同位相の振動系の形成には複数点からの散乱波の干渉が関与することが判明した。, The characteristics of near-inertial internal waves (NIIWs) induced by the passage of a low-pressure system on October 2007 were investigated using current data obtained from acoustic Doppler current profilers mounted on the seafloor of three mooring sites northeast of the Noto Peninsula, Japan. The observed near-inertial fluctuations showed a characteristic of NIIWs. We found that current fluctuations associated with the NIIWs were almost in-phase at three stations, and its amplitudes were larger in the middle layer (34-58 m depth) than in the surface layer on the continental slope. Because it was difficult to explain the characteristics of the observed NIIWs in terms of the elementary solution of internal wave theoretically, we performed a numerical experiment using a three dimensional level model that adopted realistic bottom topography and wind stress interpolated from Grid Point Value data (Japan Meteorological Agency). The model had a good reproduction of the amplification of NIIWs energy at the middle layer. Thus, we investigated the formation mechanism of strong and in-phase current fluctuations by a detailed analysis of the model results. The NIIWs, generated in the offshore region, propagated southward and reached the coastal area and Noto Peninsula. Scattering of the NIIWs occurred at the shallow region around the Peninsula, and the scattering waves were simultaneously induced and interfered around the mooring sites. To investigate the effect that the bottom topography contributed to the interference of the scattering waves, we performed two types of verification experiments in which shallow regions near the Noto Peninsula were deleted. These experimental results showed that the scattering waves that occurred at the continental shelf off the eastern coast of Noto Peninsula were important for the amplification of NIIWs at the middle layer, and the interference by the superposition of scattering waves from different regions around the mooring sites involved the formation of in-phase current fluctuations., 15H01726},
 pages = {203--226},
 title = {能登半島北東端沖で観測された近慣性内部波},
 volume = {24},
 year = {2015}
}