Pacific Ocean western boundary currents and the interlinked equatorial Pacific circulation system were among the first currents of these types to be explored by pioneering oceanographers. The widely accepted but poorly quantified importance of these currents-in processes such as the El Niño/Southern Oscillation, the Pacific Decadal Oscillation and the Indonesian Throughflow-has triggered renewed interest. Ongoing efforts are seeking to understand the heat and mass balances of the equatorial Pacific, and possible changes associated with greenhouse-gas-induced climate change. Only a concerted international effort will close the observational, theoretical and technical gaps currently limiting a robust answer to these elusive questions.

A new generation of books on group theory for physicists has appeared over the last ten years . Many of them deal only with elementary particle physics or with condensed matter physics . This volume by Prof. Jin-Quan Chen is a serious attempt to cover a broad range of applications of group theory to physics. It begins with an introduction to the elements of group theory and the theory of representations . Representations of finite groups and character theory are carefully treated and applied in later chapters to point groups and space groups, where thorough and practical information is given about molecular and crystal groups.The permutation group is discussed in detail, and its use in finding the irreps of unitary groups is carefully and completely covered. Lie groups and Lie algebras are treated sufficiently to enable their use in elementary particle physics, with a thorough presentation of Dynkin diagrams and the reduction of products.For spectroscopy and, in particular , nuclear spectroscopy, this is the first up-to-date and thorough treatment of the calculation of isoscalar factors and coefficients of fractional parentage. There are extensive tables and indications of computational methods. With his collaborators in Nanjing and Philadelphia, Chen has contributed extensively to new developments over the past decade . These researches are incorporated into the present book, of which a preliminary version was published a few years ago in the People's Republic of China.It has been a pleasure for me to talk with Chen many times about group theory and a special pleasure to welcome the appearance of this book. Morton Hamermesh PrefaceConscious of the frustration we experienced as we tried to learn group theory, and apply it to problems in physics , F. Wang , M. J. Gao and I endeavoured in 1974 to carry out a systematic reform of traditional group representation theory . Our aim was to establish a new approach to group representations in accordance with the concept and method used in quantum mechanics, so that it would be much more accessible to physicists and chemists. Mr. Pei-tying Wang typed the initial draft of Chapters 4-9, and my son, Bing-Qing wrote several software codes for facilitating the typing and proof-reading of the manuscript . Without their help it would be inconceivable that the re-writing could have been accomplished within half a year.Special mention must be made of Professors B. Bayman, M. Hamermesh and K.T. Hecht for their constant interest and many illuminating discussions, and D . H. Feng , who gave me the opportunity and encouragement to teach a course on group theory at Drexel University.Last but not least I would like to thank Professors

Using recently collected current and hydrographic data, we provide a high resolution picture of the subinertial flow and estimate the volume transport through the Luzon Strait. The distribution of the subinertial flow shows a strong westward flow around 100 m in the northern part of the Luzon Strait, while the eastward flow is confined to the deeper layers, mostly at depths around 1000 m. The total volume transport is estimated to be 6 ± 3 Sv during the period of observations from October 4 to 16, 2005. The observations also confirm that the Luzon Strait transport has a sandwiched vertical structure. The net westward volume transport in the deep (>1500 m) layer of the Luzon Strait reaches 2 Sv.

[1] Mesoscale eddy properties in the northwestern subtropical Pacific Ocean are investigated by analyzing 22,567 cyclonic eddies (CEs) and 26,365 anticyclonic eddies (AEs) detected from 19 year altimetric sea level records. Eddy occurrence frequency and kinetic energy are prevailingly high in the Subtropical Countercurrent zonal band between 19 N and 26 N and further elevated near the Luzon-Taiwan coast. A general superiority of AEs is observed at most latitudes except between 19 N and 22 N, where the CE number is larger. The modal radius and mean lifespan of the CEs (AEs) are 134 km and 11.2 weeks (121 km and 10.9 weeks), respectively. After generation, most eddies propagate westward with a mean speed of 7.2 cm s À1 and deflect northward following the Kuroshio along the Luzon-Taiwan coast. Three-dimensional eddy structures are further explored with composite eddy images in five subregions constructed by surfacing Argo temperature/salinity data into altimeter-detected eddy areas. Due to the existence of mode waters in the main thermocline, eddy-induced temperature anomaly exhibits a double-core vertical structure which is especially evident in CE images. Because of the vertical water mass distribution, salinity anomaly features a sandwich-like pattern which is more evident in AE images. Also revealed is the significant structure difference in these five subregions. Eddies are greatly intensified as they approach the western boundary, inducing larger temperature and salinity anomalies and influencing deeper ocean. Along the Luzon-Taiwan coast, AEs are preferentially strengthened by the northward background flow.

We perform a dynamical calculation of the ∆∆ dibaryon candidates with IJ P = 03 + and IJ P = 30 + in the framework of two constituent quark models: the quark delocalization color screening model and the chiral quark model. Our results show that the dibaryon resonances with IJ P = 03 + and IJ P = 30 + can be formed in both models. The mass and width of IJ P = 03 + state are smaller than that of IJ P = 30 + state due to the one-gluon-exchange interaction between quarks. The resonance mass and decay width of IJ P = 03 + state in both models agree with that of the recent observed resonance in the reaction pn → dπ 0 π 0 . The IJ P = 30 + ∆∆ is another dibaryon candidate with smaller binding energy and larger width. The hidden-color channel coupling is added to the chiral quark model, and we find it can lower the mass of the dibaryons by 10-20 MeV.

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The recent experimental results of LHCb collaboration suggested the existence of pentaquark states with charmonium. To understand the structure of the states, a dynamical calculation of 5-quark systems with quantum numbers) ± is performed in the framework of chiral quark model with the help of gaussian expansion method. The results show that the negative parity states can be bound states while all of the positive parity states are the scattering states. The Pc(4380) state is suggested to be the bound state of Σ * c D. Although the energy of ΣcD * is very close to the mass of Pc (4450), the inconsistent parity prevents the assignment. The calculated distances between quarks confirm the molecular nature of the states. Other five-quark bound states of the combination of ΣcD and Σ * c D * are also found in the region about 4.3GeV and 4.5GeV.

We demonstrate, using two different quark models of hadrons, that there should be isodoublets of dibaryons with strangeness -3 and 7 = 1,2, which are stable with respect to strong decay.