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21.
Geographic information system (GIS) based methodologies are widely used to various problems. However, its potential for application to strategic maritime search and rescue (SAR) planning remains largely unexplored. To investigate the applicability of GIS-based tools to this problem, this paper presents an approach to evaluate accessibility and response times in a sea area. Such information aids to objectify the response effectiveness of a SAR system, which is important for rational resource allocation. The presented methodology accounts for the main characteristics of maritime response, namely spatial accessibility, capabilities of search and rescue units (SRUs) and prevailing wave conditions, which affect the attainable SRU speeds. An application to the Finnish areas of the Gulf of Finland is shown. Despite the existence of some difficulties with currently available tools (e.g. accurate and user-friendly spatial wave models and challenges with using raster-based methods in topologically complex areas) and limitations in knowledge (e.g. the SRU capabilities in actual operations), the results indicate that the methodology provides good opportunities for enhancing maritime decision making.  相似文献   
22.
The relationship between the intensity of the South China Sea summer monsoon (SCSSM) and the Nino3.4 index and anomalous atmospheric circulation patterns associated with a strong and weak SCSSM are investigated using the NCEP/NCAR reanalysis data, Extended Reconstructed Sea Surface Temperature (ERSST) data and Climate Prediction Center Merged Analysis of Precipitation (CMAP) data. The SCSSM is significantly positively correlated with the Nino3.4 index in the succeeding northern autumn and winter. In the strong minus weak SCSSM composite, a positive East Asia-Pacific teleconnection (EAP) pattern and a negative Europe-Asian-Pacific teleconnection (EUP) pattern appear in the 500 hPa height difference field; low-level cross-equatorial flows are strengthened over the Maritime Continent (MC) region; positive (negative) precipitation anomalies occur in the South China Sea and western north Pacific (MC). A possible mechanism through which SCSSM affects ENSO is proposed. A strong (weak) SCSSM strengthens (weakens) cross-equatorial flows over the MC. The anomalous cross-equatorial flows cool (warm) the SST around the MC through enhanced (reduced) surface latent heat fluxes. The cooling (warming) further leads to suppressed (enhanced) convection over the MC, and causes the anomalous westerly (easterly) in the equatorial western Pacific, which favors the onset of El Ni?o (La Ni?a) through modulating the positive air-sea feedback process.  相似文献   
23.
This paper discusses the results of interpreting seismic profiles on the Earth’s crust of the Maritime Territory and Sea of Japan performed during the 20th century by the Sakhalin Integrated Research Institute and by the Schmidt Joint Institute of Physics of the Earth, Russian Academy of Sciences. The seismic profiles confirmed the presence of structural features under the Maritime Territory and the Sea of Japan that were revealed previously from geological data, such as spreading zones, rifts, deep-seated faults, overthrusts, and subduction zones, suggesting an active type of continental margin in the Far East region. We assumed that a high occurrence of the asthenospheric layer enclosing magmatic chambers explains the high activity of tectonic processes in the Far Eastern continental margin. The identified system of rifts and spreading centers supports this assumption.  相似文献   
24.
2007年,Ashok等揭示了赤道太平洋区域存在一种三极型分布海表温度异常并称之为厄尔尼诺-Modoki,同时定义了相应的海表温度异常指数EMI(记为IEM)。在此基础上,利用英国哈得来中心逐月海表温度资料、美国NCEP/NCAR月平均再分析数据集、美国国家海洋和大气管理局(NOAA)逐月降水资料(CMAP),通过在太平洋海表温度异常中扣除厄尔尼诺-Modoki信号后,在Nino1+2区域上定义了东太平洋型海表温度异常指数EPNI(IEPN)。据此,由IEPN和IEM可构成描述热带太平洋海表温度异常变化的一对指数。分析了两个指数相应的海气状态及对海洋性大陆区域气候异常的影响。结果表明,厄尔尼诺-Modoki和东太平洋型海表温度异常及其影响存在显著差异。在北半球夏季,当IEM处于正位相时,热带太平洋海表温度异常呈现“负-正-负”的结构,海洋性大陆大部分区域海表温度异常为负,此时对流层低层太平洋地区辐合,海洋性大陆地区辐散,对流层高层太平洋地区辐散,海洋性大陆地区辐合。对应于辐合辐散中心,存在着自赤道中太平洋分别向赤道东太平洋和海洋性大陆中东部地区的异常垂直环流圈,同时也存在自海洋性大陆西部向印度洋西部的垂直环流。大气在海洋性大陆区域北部加热,南部冷却;在太平洋地区西部加热而东部冷却;在海洋性大陆区域10°N以南降水偏少,而10°N以北降水偏多。当IEPN处于正位相时,热带太平洋海表温度异常呈现“西负东正”分布型,海洋性大陆区域海表温度异常呈现“西正东负”分布,对流层低层海洋性大陆地区辐散中心范围偏大、位置偏东、强度偏强,太平洋地区辐合中心范围偏小、位置偏东,热带环流异常在垂直方向上呈斜压结构,海洋性大陆区域北部大气加热而南部冷却,太平洋地区大气均呈加热正异常,海洋性大陆大部分区域降水均偏少,赤道太平洋降水偏多。以上这些结果有利于深刻理解热带太平洋海表温度异常的特征及其对海洋性大陆区域气候的影响。  相似文献   
25.
湄洲湾海雾的初步分析   总被引:1,自引:0,他引:1  
分析福建湄洲湾1985-1992年海雾的气候特点,发现79%的海雾发生在2-5月。应用中国气象局北京气象中心出版的历史天气图,对本区海雾进行天气学分型,结果表明,有89%的海雾出现在锋面偏北,南高北低,东脊型中,利用850hPa天气型的消空条件,结合气象因子和单站资料,得出了湄洲湾海雾的短期预报指标,并建立了预报方程。  相似文献   
26.
The increased maritime accidents attributable to communication barriers have raised great concern about international shipping safety. The requirement for effective communication has been contained in the compulsory part of the International Convention on Standards of Training, Certification and Watchkeeping for Seafarers in 2010. However, many Chinese seafarers still experience difficulty in communicating with foreign seafarers at sea even though they passed the English exams required for a Certificate of Competency. Literature argues that the outcomes of maritime English education are not satisfactory. However, this claim is too general and has not been substantiated with empirical evidence. Using a mix of qualitative and quantitative methods, this paper reveals that English communicative incompetence of Chinese seafarers was attributable to the maritime English examinations system, teaching materials, teaching methods and teachers and students themselves. Recommendations were made to improve maritime cadets’ English communicative competence.  相似文献   
27.
Transition to low carbon sea transport is a logical response to the extreme dependency of the Pacific Islands region on imported fossil fuel, its significant vulnerability to the effects of climate change and the critical shipping needs of Pacific Island countries (PICs). Building on previous work in low carbon sea transport in the Pacific, this paper further considers the barriers to achieving such transition by assessing, through a ‘post-Paris Agreement’ lens, the Intended Nationally Determined Contributions (INDCs) submitted by PICs and contrasting these to the near total lack of investment and planning for low carbon transition in the transport sector with the parallel occurrence in the electricity sector where ~USD 2 billion of donor investment is deployed or queued despite electricity using only ~20% of fossil fuel across the region. Consistent with recent international studies, inadequate and inappropriate financing and policy have been identified as dominant transition barriers for low carbon sea transport development in PICs. This paper further examines the regional level barriers to policy development, and finds them inhibited by the silo nature of the major regional actors. The implications that the Paris Agreement has for climate financing to support the essential research and capacity development needed to underpin a successful low carbon sea transport transition strategy at any useful scale and speed are also considered in this paper.  相似文献   
28.
李巧玲 《热带地理》2015,35(5):701-707
在分析雷州具有临海、港湾众多等自然地理特征,是中国海上丝路必经之地的历史基础上,阐述海上丝路文化在雷州广泛而深入的传播,在农业土地利用、器艺制作、建筑、以佛教和妈祖崇拜为主的观念文化等方面留下深刻影响,并在很大程度上决定雷州文化具有多元、海洋、开放、包容、冒险等文化特质和风格。在当代背景下,应充分认识雷州海上丝路文化资源的历史价值、科研价值和经济价值,并通过开展海上丝路文化古迹普查,建立区域合作关系,构建海丝会展平台,进行宗教文化交流,参与海上丝绸之路申遗等途径,对雷州海上丝路文化资源加以深度发掘及开发利用,为建设“一带一路”之海上丝路服务。  相似文献   
29.
Numerous national governments and supranational organizations such as the OSPAR Commission, the European Union and the United Nations Educational, Scientific and Cultural Organization (UNESCO) have underlined the importance of maritime spatial planning (MSP) for balancing and solving conflicts between the needs of different sectors and conservation in the marine space. In the last decade, many maritime spatial plans have been developed around the world. The drivers to develop these plans and the approaches to find solutions for the particular problems differ significantly. The Portuguese national marine jurisdiction is one of the largest in Europe. For the continental part, a maritime spatial plan was initiated in 2009, and entered in 2010 in the final stage of approval. One of the driving forces for this MSP initiative was the claim to extend its continental shelf. The development process was led by a multidisciplinary team. Despite the challenges, the existing as well as potential future marine resources and activities were characterized, mapped and categorized. To overcome conflicts resulting from the many overlapping uses and to assure sustainable development of all sectors, a conflict analysis and evaluation of potential future uses were necessary. The applied zoning scheme represented an exercise of conflict solving and proved to be a powerful tool to promote discussion and participation among stakeholders. The successful implementation of Portuguese MSP will rely largely on its ability to provide efficient management, financial and legal mechanisms to achieve the integration of all strategies and spaces under the Portuguese maritime jurisdiction.  相似文献   
30.
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