Distribution characteristics of seamount cobalt-rich ferromanganese crusts and the determination of the size of areas for exploration and exploitation

In 2001, the International Seabed Authority （ISBA） initiated the consideration relating to the Regulations for Prospecting and Exploration for Hydrothermal Polymetallic Sulphides and Cobalt-rich Ferromanganese Crusts in the Area at its 7th session. Since then, the consideration of the Regulations has been mainly focused on the size of areas to be allocated for exploration and exploitation of the crusts. This paper, based on the investigation data and the analysis of the distribution characteristics of the crusts, suggests a model for determining the size of areas for exploration and exploitation of the crusts, taking into account various factors such as production scale, crust thickness and grade, mineable area proportion, recovery efficiency, exploration venture, and so on. Through the modeling, the paper suggests that the exploration area （the area covered by each application for approval of a plan of work for exploration of cobalt-rich crusts） shall be 4 856 km2 and the exploitation area （the mine site area） shall be 1 214 km2, for 20 years of 1 million wet tonnes annual production.

Wavelet analysis of coastal-trapped waves along the China coast generated by winter storms in 2008

This study applies the wavelet analysis to the tidal gauge records, alongshore winds, atmospheric temperature and pressure along the China coast in winter 2008. The analysis results show three events of sea level oscillations （SLOs） on the shelf induced by winter storms. The first event occurred from January 9 to 21. The SLO periods were double-peaked at 1.6-5.3 and 7.0-16.0 d with the power densities of 0.04-0.05 and 0.10-0.15 m^2.d, respectively. The second event occurred from February 5 to 18. The SLO period was single-peaked at 2.3-3.5 d with power density of 0.03-0.04 m^2.d. The third event occurred from February 20 to March 8. The SLO periods were double- peaked at 1.5-4.3 and 6.1-8.2 d with the power densities of 0.08-0.11 and 0.02-0.08 me.d, respectively. The SLOs propagated along the coast from Zhejiang in north to Guangdong in south. The phase speeds ranged about 9-29 m/s from Kanmen to Pingtan, 5-11 m/s from Xiamen to Huizhou and 11-22 m/s from Huizhou to Shuidong. The dispersion relation of the SLOs shows their nature of coastal-trapped wave.

A study on the relationships between the wave height and the El Nino in the north area of the South China Sea

On the basis of the European Centre for Medium-range Weather Forecasts （ECMWF） 20 a wind field reanalysis data, the wave field of the north area of the South China Sea is calculated with the combination of the HIRHAM wind field model and the SWAN wave model. Then a significant wave height compared with the E1 Nifio index to study the relationships between these variables. The following conclusions are drawn： （1） the wave height of the South China Sea has a strong seasonal variation, the wave height is much larger in winter than in summer; （2） in the South China Sea, the monthly average wave height of the north area has a negative correlation with the Nifio3.4 index, most area of the South China Sea has a moderate correlation and the area between Taiwan Province of China and Philippines is highly correlated; and （3） in the strong E1 Nifio years, the significant wave height in the north area of the South China Sea is significantly smaller than in other years; if the E1 Nifio index variability is greater, the wave height decreases. In contrast, the significant wave height in the north area of the South China Sea is larger in the strong La Nifia years.

The ‘Two oceans and one sea' extended range numerical prediction system with an ultra-high resolution atmosphere-ocean-land regional coupled model

‘两洋一海’区域是‘21世纪海上丝绸之路’的重要空间载体,也是国防安全的核心战略海区。随着社会需求加剧,介于常规短期和气候尺度之间的延伸期(10–30天)预测的重要性逐渐突显。受限于海洋短期预报不含大气海洋快慢过程转化的信息存储机制、大气高频变化制约预报时效、全球气候预报分辨率较低、气陆海多圈层耦合机制理解不足及区域预报无较好初始化等问题,我国海洋延伸期预测工作仍是盲点,导致对一些海洋过程、灾害事件无法做出模拟及预警。本文将介绍基于区域超高分辨率多圈层耦合模型的两洋一海区域延伸期数值预测系统研制情况,包括研究内容,技术方案,创新和预期成果等。

Impact of PhaseⅢProject of Maji Mountain Port on sediment siltation in adjacent sea area

Based on a 3-D Finite Volume Coastal Ocean Model（FVCOM）, tidal dynamics has been studied in the sea area around the Phase III Project of Maji Mountain Port（MMP）. Furthermore, taking typhoon ＂Canhong＂ as an example, a storm surge and sediment model has also been established to study the impact of the Phase III Project on current flows and siltation during extreme weather. Tidal currents before and after the project have been compared. Model results show that the changes of tidal current mainly occur in the engineering areas with a magnitude change of 0.3–0.4 m/s during maximum flood and ebb tides. The flow condition for the port has been improved as the flow direction is changed to parallel to the wharf after the completion of the project. There is little siltation in the adjacent area, which will not affect the safety of ship navigation. Besides, the sudden siltation during typhoon period is relatively weak. The back silting in two days is less than 5 cm indicating no sudden siltation occurs.