Six species of Genus Cryptomonas from the East and South China Seas are reported. C.varibilis H. J. Huet L. P. Wu, C. zhanjiangensis H. J. Huet L. P. Wu and C. zhejiangensis H. J. Hu et Y. G. Li are described as new. C. profunda Butcher, C. pseudobaltica Butcher and C. chrysoides Butcher are reported as new record.
Sabaco sinicus sp. nov. is described based on material collected from Chinese coast. It has been misidentified as Asychis gangeticus Fauvel, 1932 since Uschakov and Wu (1962). Here, we recognized it as a new species based on combination of the following characters: dark-brown pigmentation spots on nuchal grooves and first three chaetigers; glandular pattern on chaetigers 4–6; preanal achaetigerous segments absent; anal plaque trumpet-shaped with a disc-shaped dorsal lobe; notochaetae consisting of geniculate capillaries and fine capillaries with or without spinose spiral bands; neurochaetae presented as a single row of rostrate uncini. Asychis gangeticus differ from the new species in having no pigmentations on body and a triangular dorsal lobe of anal plaque. Distribution region of this species have moved northward significantly from sea area south of Changjiang Estuary since the 1950s.
The presented method for numerical typhoon wave prediction is composed of a scheme for real time pressure forecasts, a marine wind numerical model and a typhoon wave numerical model.In the Northwest Pacific Ocean and China seas where water depth is over 20 m, a hybrid wave model[Wen Shengchang, Zhang Dacuo, Chen Bohai and Guo Peifang.1989, Acta Oceannlogica Sinica, 8 (1), 1-14; Zhang Dacuo, Wu Zengmao, Jiang Decai, Rang Wei, Chen Bohai, Tai R'eitao, R'en Shengchang, Xu Qichun and Guo Peifang.1992, Acta Oceanologica Sinica, 11 (2), 157-178] is employed with 10°×10° grids, while in the South China Sea and East China Sea where typhoon frequently appears, the WAM model (WAMDI Group.1988, Journal of Physical Oceanography, 18, 1755-1810) of shallow water version is embedded with (1/4)°× (1/4)° grids.The boundary condition at the open boundary of the WAM model is provided by the hybrid model.After 3 a of testing forecasts (Yang Chuncheng, Dai Mingrui and Zhang Dacuo.1992, International Symposium on Tropical Cyclone Dusaaters, October 12-16, Beijing, 404-409)and improvement, this system was put into operational use on the forecasting computer network of National Marine Environment Forecast Center of China in June, 1993.The wave predictions of 22 typhoon events show that the system is stable and prompt, and the forecast results are satisfactory.This system provides reliable numerical products for the disaster-prevention forecasts.The product is broadcasted in CCTV News at every noon.
Wave-current interaction and its effects on the hydrodynamic environment in the Beibu Gulf (BG) have been investigated via employing the Coupled Ocean–Atmosphere–Wave–Sediment Transport (COAWST) modeling system. The model could simulate reasonable hydrodynamics in the BG when validated by various observations. Vigorous tidal currents refract the waves efficiently and make the seas off the west coast of Hainan Island be the hot spot where currents modulate the significant wave height dramatically. During summer, wave-enhanced bottom stress could weaken the near-shore component of the gulf-scale cyclonic-circulation in the BG remarkably, inducing two major corresponding adjustments: Model results reveal that the deep-layer cold water from the southern BG makes critical contribution to maintaining the cold-water mass in the northern BG Basin. However, the weakened background circulation leads to less cold water transported from the southern gulf to the northern gulf, which finally triggers a 0.2°C warming in the cold-water mass area; In the top areas of the BG, the suppressed background circulation reduces the transport of the diluted water to the central gulf. Therefore, more freshwater could be trapped locally, which then triggers lower sea surface salinity (SSS) in the near-field and higher SSS in the far-field.