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The circulation of the Kuroshio northeast of Taiwan is characterized by a large anticyclonic loop of surface intrusion and strong upwelling at the shelfbreak. To study the mechanisms of Kuroshio intrusions, the vorticity balance is examined using a high-resolution nested numerical model. In the 2D depth-averaged vorticity equation, the advection of geostrophic potential vorticity (APV) term and the joint effect of baroclinicity and relief (JEBAR) term are dominant. On the other hand, in the 2D depth-integrated vorticity equation, the main balance is between nonlinear advection and bottom pressure torque. It is shown that JEBAR and APV tend to compensate, and their difference is comparable to bottom pressure torque. Perhaps most significantly, a general framework is provided for examination of vorticity balance over steep slopes through a full 3D depth-dependent vorticity equation. The 3D analysis reveals a well-defined bottom boundary layer over the shelfbreak, about 40m deep and capped by the vertical velocity maximum. In the upper frictionless layer from the surface to about 100 m, the primary balance is between nonlinear advection and horizontal divergence. In the lower frictional layer, viscous stress is balanced by nonlinear advection and horizontal divergence. The bottom pressure torque, which corresponds to the depth-integrated viscous effect, is a proxy for viscous stress divergence at the bottom. The importance of nonlinear advection is further demonstrated in a sensitivity experiment by removing advective terms from momentum equations. Without nonlinear advection, the bottom pressure torque becomes trivial, the boundary layer vanishes, and the on-shelf intrusion is considerably weakened. [ABSTRACT FROM AUTHOR]

This paper investigates the influences of deregulation on Taiwan's domestic air market, which took place in 1987. The Herfindahl-Hirschman Index, the number of effective competitors, and the concentration ratio of a defined market are used to measure the associated market structure. The market structures of three selected flight routes and the entire domestic air market of Taiwan are analysed using a time-series data set spanning 21 years. Research results indicate that the market structure indicators of all defined markets were volatile after deregulation and then became stable again, with the recent market competition being greater than it was before. This reveals that market competition increased due to deregulation - in both the entire market and the markets of specific flight routes. While the domestic air market of Taiwan is unique - with relatively short flight times and fewer numbers of airlines in the market as compared with markets that are investigated in the literature using the same indicators - the results are promising in that those indices capture the variation of Taiwan's domestic air market due to the implementation of the deregulation policy. It implies that those measures are also suitable for markets with a relatively low degree of competition or which are relatively small scale. [ABSTRACT FROM AUTHOR]

During the typhoon season, storm surges often instigate serious damages to the coastal areas of Taiwan. In August 1994, typhoon Doug almost completely destroyed the breakwaters and docking facilities in the Lungtung harbor at the northeast tip of Taiwan. The estimated maximum sea level rise was about 3m. Analyses of tide, wave and meteorological records indicate that the amplitude and spatial pattern of storm surges are related to the local wind speed, direction and duration as well as the local geometry. A linear two-dimensional numerical model is used to quantify the storm surge structure. The model results indicate that sea levels reached a maximum of about 2 m at the peak of the storm. The largest surge, however, does not occur at where the most severe damage was located. This suggests that the wave run-up could be an important contribution to the storm surge. [ABSTRACT FROM AUTHOR]