THE EFFECT OF TIDE LEVEL ON THE TSUNAMI RESPONSE OF COASTAL HARBORS

Jiin-Jen Lee, Ziyi Huang, Zhiqing Kou, Xiuying Xing

Abstract


The tsunamis generated by the February 27, 2010 Chilean earthquake and the great Japan Tohoku earthquake on March 11, 2011 arrived at several Pacific Coast harbors when the tide levels were at low tides and persisted for several tidal cycles. Despite the significant difference in the recorded wave amplitude observed at Crescent City harbor between these two events, the energy spectrum as a function of frequency has been found to contain several spikes corresponding to the frequency range of 3×〖10〗^(-4)~10×〖10〗^(-4) Hz. This pattern in spectral density is different from several prior tsunamis observed and analyzed for Crescent City Harbor as presented by Lee, Xing and Magoon (2008). In the present study we present the reasons behind the differences in the response behavior associated with these two events. We prove that they are due to the effect of tide levels. We also show that in order to correctly decipher the resonant response characteristics to incident wave the response curves should be expressed as a function of the dimensionless wave number. The tsunami waves recorded at tide gauge station in San Diego Harbor (Southern California) are also analyzed and discussed.

Keywords


harbor resonance; Chilean earthquake tsunami; Tohoku tsunami; dimensionless wave number; fundamental resonant mode; Crescent City Harbor; San Diego Harbor

References


Berkhoff, J.C.W. 1972. Computation of Combined Refraction-diffraction, Proc. 13th Coast. Eng. Conf., ASCE, New York, 471-490.

Gehlken, M., T. Shin, and G. Bledsoe. 2011. Tsunami Causes Boat Damage in San Diego, National Broadcasting Company (NBC), San Diego. http://www.nbcsandiego.com/news/local/TsunamiShatters-Barge-in-San-Diego-Bay-117836593.html.

Lee, J.J. 1971. Wave-induced Oscillations in Harbors of Arbitrary Geometry, J. Fluid Mech., 45(2), 375-394.http://dx.doi.org/10.1017/S0022112071000090

Lee, J.J. and F. Raichlen. 1972. Oscillations in Harbors with Connected Basins, ASCE J. Waterway, Ports, Coastal and Ocean Engineering Division, 98(WW3), 311-332.

Lee, J.J. and X.Y. Xing. 2010. Computer Modeling for Harbor Planning and Design, Handbook of Coastal and Ocean Engineering (Edited by Y.C. Kim), World Scientific, 695-722.

Lee, J.J., X.Y. Xing and O. Magoon. 2008. Uncovering the Basin Resonance at Crescent City Harbor Region, Proceedings of ICCE 2008, 2, 1210-1222.

Magoon, O.T. 1965. Structural Damage by Tsunamis, Coastal Engineering, Satan Barbara Specialty Conference, ASCE, 35-68.

Powers, D.M. 2005. The Raging Sea: The Powerful Account of the Worst Tsunami in U.S. History, Kensington Publishing Corporation.

Raichlen, F. and J.J. Lee. 1992. Oscillation of Bays, Harbors, and Lakes, Handbook of Coastal and Ocean Engineering, Gulf Publishing Company, Chapter 13.

Wilson, R. I., L.A. Dengler, M. R. Legg, K. Long, and K.M. Miller. 2010. The 2010 Chilean Tsunami on the California Coastline, Seism. Res. Lett., 81 (3), 545-546.

Zelt, J.A. and F. Raichlen. 1990. A Lagrangian Model for Wave-induced Harbor Oscillations, J. Fluid Mech., 213, 203-225.http://dx.doi.org/10.1017/S0022112090002294


Full Text: PDF

Creative Commons License
This work is licensed under a Creative Commons Attribution 3.0 License.