研究内容（目的・方法） 河川水はその流量、温度、河口域や海底の構造などを反映しながら次第に海水と混合して外洋へと流出して行きます。その混合拡散を正確に見積もることは湾内での化学物質の動態やその生物生産への寄与を見積もる上で重要です。本研究のために開発された新型の観測装置 YODA Profiler (Masunaga and Yamazaki, 2014) や数値モデル SUNTANS (Fringer et al., 2006) を用いて、大槌湾内における河川水の混合拡散のプロセスの解明を行っています。研究の結果、潮汐、内部潮汐と風の３つの要素が湾内の河川水の混合に強く寄与していることがわかりました。
参考文献
Masunaga E, Fringer O, Yamazaki H: An observational and numerical study of river plume dynamics in Otsuchi Bay, submitted to Journal of Oceanography, November 2014.
Herminio Foloni-Neto, Rolf Lueck, Yoshiro Mabuchi, Hisato Nakamura, Masakazu Arima, and Hidekatsu Yamazaki, 2014: A New Quasi-Horizontal Glider to Measure Biophysical Microstructure, J. Atmos. Oceanic Technol., 31, 2278–2293.
Okayasu, A., T. Shimozono, H. Yamazaki, T. Nagai and S. Sato 2013: Severe erosion of sandbar at Unosumai river mouth, Iwate due to 2011 Tohoku Tsunami, Coastal Dynamics 2013.
McManus, M.A., E. Berdalet, J. Ryan, H. Yamazaki, J.S. Jaffe, O.N. Ross, H. Burchard, I. Jenkinson, F. Chavez 2013: Global Ecology and Oceanography of Harmful Algal Blooms, GEOHAB Core Research Project: HABs instratified systems. Workshop on“Advances and challenges for understanding physical-biological interactions in HABS in stratified environments” IOC and SCOR, Paris, France and Newark, Delaware, USA, 96pp.
Masunaga, E., H. Yamazaki, T. Nagai and O. Fringer 2013:Resuspension and lateral dispersal of sediments due to shoaling internal waves, IMBER UPDATE No.25, 7-10, December 2013.
Masunaga, E and Yamazaki, H., 2014. A new tow-yo instrument to observe high-resolution phenomena. Journal of Marine Systems 129: 425-436. http://dx.doi.org/10.1016/j.jmarsy.2013.09.005
Raine, R., E. Berdalet, M. McManus and H.Yamazaki 2014: Preface Harmful algal blooms in stratified systems, Deep-Sea Res. II, 101, 1-3,http://dx.doi.org/10.1016/j.dsr2.2014.01.005
Berdalet, E., M.A. McManus, O.N. Ross, H. Burchard, F.P. Chavez, J.S. Jaffe, I.R. Jenkinson, R. Kudela, I. Lips, U. Lips, A. Lucas, D. Rivas, M.C. Ruiz-de la Torre, J. Ryan, J.M. Sullivan and H. Yamazaki 2014: Understanding harmful algae in stratified systems: Review of progress and future directions, Deep-Sea Res. II, 101, 4-20,http://dx.doi.org/10.1016/j.dsr2.2013.09.042
Yamazaki, H., C. Locke, L. Umlauf, H. Burchard, T. Ishimaru and D. Kamykowski 2014: A Lagrangian model for phototaxis-induced thin layer formation, Deep-Sea Res. II, 101, 193-206, http://dx.doi.org/10.1016/j.dsr2.2012.12.010
Doubell, M., J.C. Prairie and H. Yamazaki 2014: Millimeter scale profiles of chlorophyll fluorescence: Deciphering the microscale spatial structure of phytoplankton, Deep-Sea Res. II, 101, 207-215,http://dx.doi..org/10.1016/j.dsr2.2012.12.009.
Mandal, S., C. Locke, M. Tanaka and H. Yamazaki 2014: Observations and models of highly intermittent phytoplankton distributions, Plos One, 9(5), e94797.
