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Using observational and reanalysis data sets, we investigated interannual variability in the Kuroshio in the East China Sea (ECS‐Kuroshio). We exhibited that the surface velocity and position of the ECS‐Kuroshio were synchronized on a quasi‐3‐year interannual timescale during 2005–2016. We further demonstrated that: (a) during 2005–2016, wind stress curl variability related to the El Niño–Southern Oscillation (ENSO) played a leading role in the interannual ECS‐Kuroshio variability by exciting baroclinic Rossby waves along the subtropical countercurrent (STCC) zone east of Taiwan; (b) mesoscale eddy activities in the STCC zone, especially long‐lived (≥150‐day lifetime) cyclonic eddies, probably played a secondary role in the interannual ECS‐Kuroshio variability. In addition, we showed that the occurrence of the quasi‐3‐year interannual variability of the ECS‐Kuroshio since 2005 was likely linked to the following changes in the ENSO‐related atmospheric circulation: (a) The primary ENSO timescale changed from a quasi‐5‐year period in 1993–2004 to a quasi‐3‐year one in 2005–2016; (b) Over the central equatorial Pacific along with the eastern tropical Indian Ocean, the sea surface temperature in 2005–2016 varied with a more intense amplitude than in 1993–2004, which resulted in a different western North Pacific atmospheric response to the ENSO in 2005–2016 from that in 1993–2004. Plain Language Summary: The Kuroshio, which serves as the western boundary current of the North Pacific subtropical gyre, is one of the most important elements that control the oceanic and atmospheric conditions around the East China Sea (ECS). In this study, we found that the surface velocity and position of the ECS‐Kuroshio were synchronized on a quasi‐3‐year interannual timescale during 2005–2016. We further determined that, during 2005–2016, baroclinic Rossby waves along the subtropical countercurrent (STCC) zone east of Taiwan, which were excited by wind forcings related to the El Niño–Southern Oscillation (ENSO), played a leading role in the interannual ECS‐Kuroshio variability, and mesoscale eddy activities in the STCC zone probably played a secondary role. Moreover, we suggested that, since the mid‐2000s, the change of the primary ENSO timescale and the amplification of the sea surface temperature variability in the tropical ocean have led to the occurrence of the quasi‐3‐year interannual variability of the ECS‐Kuroshio through the western North Pacific atmospheric response to the ENSO. Key Points: Kuroshio in the East China Sea varied on a quasi‐3‐year interannual timescale during 2005–2016El Niño–Southern Oscillation‐related atmospheric circulation played a leading role in this interannual variability by exciting baroclinic Rossby wavesMesoscale eddy activities, especially long‐lived (≥150‐day) cyclonic eddies, probably contributed secondarily to this interannual variability [ABSTRACT FROM AUTHOR]

Topographic Rossby waves (TRWs) are oscillations generated on sloping topography when water columns travel across isobaths under potential vorticity conservation. From our large-scale observations from 2016 to 2019, near-65-day TRWs were first observed in the deep basin of the South China Sea (SCS). The TRWs propagated westward with a larger wavelength (235 km) and phase speed (3.6 km day−1) in the north of the array and a smaller wavelength (80 km) and phase speed (1.2 km day−1) toward the southwest of the array. The ray-tracing model was used to identify the energy source and propagation features of the TRWs. The paths of the near-65-day TRWs mainly followed the isobaths with a slightly downslope propagation. The possible energy source of the TRWs was the variance of surface eddies southwest of Taiwan. The near-65-day energy propagated from the southwest of Taiwan to the northeast and southwest of the array over ~100–120 and ~105 days, respectively, corresponding to a group velocity of 4.2–5.0 and 10.5 km day−1, respectively. This suggests that TRWs play an important role in deep-ocean dynamics and deep current variation, and upper-ocean variance may adjust the intraseasonal variability in the deep SCS. Significance Statement: Topographic Rossby waves (TRWs) play an important role in deep-ocean dynamics and deep current variation, and they have potential impacts on sediment transport and abyssal biogeochemical processes. From large-scale observations of abyssal currents in the deep basin of the South China Sea (SCS), energetic near-65-day TRWs with a westward phase speed of 1.2–3.6 km day−1 were first observed. The ray-tracing model was used to identify the energy source and propagation features of the TRWs. The possible energy source was the variation of mesoscale eddies southwest of Taiwan. The study has implications for adjustments to the energy and intraseasonal variability generation in the deep basin of the SCS. [ABSTRACT FROM AUTHOR]

In Taiwan, the first human-infecting H6N1 avian influenza virus was isolated in 2013. To better understand the origin, evolutionary relationship and pathogenesis of the H6N1 virus, we studied the adaptive evolution and evolutionary dynamics of the hemagglutinin (HA) genes of the H6N1 virus in Taiwan. We felt that such studies woud contribute to the further study and control of the virus. Datasets were gained from the Flu and Global Initiative on Sharing All Influenza Data (GISAID) databases. Then, phylogenetic trees and evolutionary dynamics were reconstructed. The evolutionary rate and characterization of adaptive evolution were analyzed by bioinformatic methods. Results indicated that the HA genes of H6N1 in Taiwan were divided into at least five types, and that the new types that the infected human H6N1 belonged to could be local advantage type at present. Evolutionary dynamics revealed the viral population expanded first at the end of 1971, reduced sharply in 2008, and then increased slightly. Three sites were identified under positive selection, suggesting that various sites might increase the adaptive ability of the virus. Eighty-nine sites were under negative selection, revealing that these sites might play an important role in the replication and epidemiology of the virus. Interestingly, site 329 upstream from the cleavage site was also under negative selection, suggesting that this site might be associated with the virulence of H6N1. These data suggest that the HA genes of the Taiwanese H6N1 virus have been undergoing adaptive evolution, and that an outbreak may occur again. Hence, more attention should be paid to the identified sites, to enable timely monitoring and control of a future epidemic.

Objective: To analyze the output of scientific publications in obstetrics and gynecology journals from 3 principal regions of China: mainland China, Taiwan, and Hong Kong., Methods: Information on article numbers, impact factors, citation reports, and publication in high-impact obstetrics and gynecology journals by Chinese authors between January 1, 2000, and December 31, 2009, was extracted from PubMed and WoS databases. Comparisons of quantity and quality were done by Kruskal-Wallis and rank-sum tests., Results: There were 3044 articles from mainland China (n=1042), Taiwan (n=1304), and Hong Kong (n=698). The cumulative impact factors and citations of articles from Taiwan were highest among the 3 regions. In terms of average impact factor and number of citations per article, Hong Kong exceeded mainland China and Taiwan. Fertility and Sterility, Human Reproduction and Gynecologic Oncology were among the most popular obstetrics and gynecology journals used by authors in the 3 regions., Conclusion: The annual number of articles published in obstetrics and gynecology journals from the 3 regions of China increased during the past decade, especially for mainland China. However, the quality of articles from mainland China arouses attention because the average citation of articles from Hong Kong and Taiwan was higher than that of articles from the mainland., (© 2013.)

Ocean current profiling using ocean acoustic tomography (OAT) was conducted in the Kuroshio Current southeast of Taiwan from August 20 to September 15, 2009. Sound pulses were transmitted reciprocally between two acoustic stations placed near the underwater sound channel axis and separated by 48 km. Based on the result of ray simulation, the received signals are divided into multiple ray groups because it is difficult to resolve the ray arrivals for individual rays. The average differential travel times from these ray groups are used to reconstruct the vertical profiles of currents. The currents are estimated with respect to the deepest water layer via two methods: An explicit solution and an inversion with regularization. The strong currents were confined to the upper 200 m and rapidly weakened toward 500 m in depth. Both methods give similar results and are consistent with shipboard acoustic Doppler current profiler results in the upper 150 m. The observed temporal variation demonstrates a similar trend to the prediction from the Hybrid Coordinate Ocean Model.