Complex Singular Value Decomposition Analysis of Equatorial Waves in the Pacific Observed by TOPEX/Poseidon Altimeter

Abstract The mean of the sea level deviation data derived from the TOPEX/Poseidon altimeter in the equatorial Pacific, between 10°S and 10°N, and between 120°E and 78°W, from cycles 2 to 136 (3 October 1992–2 June 1996), are extracted using a maximum–minimum average method. Then, two-dimensional (2D) sea level deviation time series are developed to visualize the dynamics of equatorial waves. The complex singular value decomposition (CSVD) method is applied to decompose these 2D time series into empirical orthogonal modes. Using this method, zonal and meridional structures, propagation directions, periods, and propagation speeds of these empirical modes are obtained. The first empirical mode is propagating westward, and its structure is asymmetric to the equator. It has an average phase speed c = −0.6 m s−1 within 4°–6°N and c = −0.4 m s−1 within 6°–8°S, respectively, and a period of 15 months, which is associated with an interannual Rossby wave. The second empirical mode is propagating eastward along the ...

[1]  J. Boulanger,et al.  Propagation and reflection of long equatorial waves in the Pacific Ocean during the 1992–1993 El Niño , 1995 .

[2]  The influence of thermocline slope on equatorial thermocline displacement , 1981 .

[3]  R. Cheney,et al.  GEOSAT Altimeter Observations of Kelvin Waves and the 1986-87 El Ni�o , 1988, Science.

[4]  S. Philander.  Equatorial Waves in the Presence of the Equatorial Undercurrent , 1979 .

[5]  Equatorial solitary waves Part 4. Kelvin solitons in a shear flow , 1984 .

[6]  C. Eriksen,et al.  Wind-Generated Equatorial Kelvin Waves Observed Across the Pacific Ocean , 1983 .

[7]  Chung-Ru Ho,et al.  Observation of equatorially trapped waves in the Pacific using Geosat altimeter data , 1995 .

[8]  D. Chelton,et al.  Global Observations of Oceanic Rossby Waves , 1996, Science.

[9]  W. White,et al.  Reflection of annual Rossby waves at the maritime western boundary of the tropical Pacific , 1990 .

[10]  J. Picaut,et al.  Equatorial Kelvin and Rossby waves evidenced in the Pacific Ocean through Geosat sea level and surface current anomalies , 1991 .

[11]  W. Liu,et al.  Seasonal and interannual variability of atmospheric convergence zones in the tropical Pacific observed with ERS‐1 scatterometer , 1997 .

[12]  Audra E. Kosh,et al.  Linear Algebra and its Applications , 1992 .

[13]  John P. Boyd,et al.  Equatorial Solitary Waves. Part I: Rossby Solitons , 1980 .

[14]  P. Chang,et al.  Propagation of an equatorial Kelvin wave in a varying thermocline Journal of Physical Oceanography , 1990 .

[15]  C. Périgaud,et al.  Observation of long equatorial waves in the Pacific Ocean by seasat altimetry , 1987 .

[16]  A. E. Gill.  Atmosphere-Ocean Dynamics , 1982 .

[17]  T. Barnett.  Interaction of the Monsoon and Pacific Trade Wind System at Interannual Time Scales Part I: The Equatorial Zone , 1983 .

[18]  Chung-Ru Ho,et al.  The Effects of Shear Flow on Propagation of Rossby Waves in the Equatorial Oceans , 1994 .

[19]  D. Luther,et al.  Observations of long period waves in the tropical oceans and atmosphere , 1980 .

[20]  J. Boulanger,et al.  Evidence of Boundary Reflection of Kelvin and First-Mode Rossby Waves , 1996 .