Operational Oceanography System applied to the Prestige oil-spillage event

This contribution describes the procedure used during the Prestige oil-spillage event, by means of an Operational Oceanography System, and the behaviour of the present prediction tools (hydrodynamic and dispersion models) applied to it. The accuracy of these tools is estimated by a reanalysis of field data transmitted by a sea surface drifting buoy, released at the time of the oil spill. The numerical models applied were the Regional Ocean Modeling System (ROMS), fed by the available six-hourly NCEP atmospheric information, together with a Lagrangian Particle-Tracking Model (LPTM). ROMS has been used to estimate the current fields for the Bay of Biscay, whilst the LPTM has provided the oil spill trajectories. The results demonstrate that the accuracy of the numerical models depends upon the quality of the meteorological input data. In this case, the current fields at the sea surface, derived by ROMS, have been underestimated by the wind fields of the NCEP reanalysis data. An efficient calibration of these wind fields, with data provided by the Gascony buoy (fixed oceanic and atmospheric station), achieves more realistic looking results; this is reflected in the comparison between the buoy trajectory predicted numerically and the tracked movements of the drifting buoy.     

论郑和航海精神与我国和谐海洋观

长期以来我国对具有中国特色的新海洋观理论的探讨研究,几近空白。郑和下西洋六百多年,留下了历史的追思与遗憾,文章论述了郑和航海精神与历史遗产;认为今天的很多经济社会问题是郑和那个时代所没有的。提出了具有我国特色的和谐海洋观观点。指出经略海洋把全球资源配置与经济目的紧密联系起来;谋划海洋获取优质能源等资源,走可持续的和谐发展道路;促进国际和平,走交流合作之路;应是今天中国和谐海洋观的三个重要组成部分。     

Exploring relationships between recruitment of European hake (Merluccius merluccius L. 1758) and environmental factors in the Ligurian Sea and the Strait of Sicily (Central Mediterranean)

This paper explores the relationships between the spatial patterns of the distribution of the young hakes of the year (YOY) and the oceanographical features in two areas of the Central Mediterranean (the Ligurian Sea and the Strait of Sicily), characterised by the occurrence of straits and channels. Comparative and correlative approaches were used to investigate coupling between biological and physical patterns. Density indices of the YOY were derived from annual trawl surveys from 1994 to 2004 in spring and autumn. Mean patterns of the YOY distributions were compared with the mesoscale oceanographical features reported in literature. No evident trends in recruitment strength were found in either areas. Inter-annual variability in YOY abundance in the Ligurian Sea was higher than in the Strait of Sicily. The location of nursery grounds in the study areas coincides with zones of relatively higher production, where upwelling and other enrichment processes regularly occur. The presence of predictable eddies and the frontal systems play a major role in the localization of nursery areas in the Strait of Sicily, maintaining their stable position throughout the years. The strongest transport of southern waters from the Tyrrhenian to the Ligurian Sea, due to the East Corsica Current, which is negatively correlated to winter North Atlantic Oscillation, is associated with the highest abundance of hake recruits in the nurseries of the Northern Ligurian Sea.