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71.
利用1979-2015年NCEP/NCAR月平均再分析资料、美国国家海洋和大气管理局(NOAA)的月平均降水资料(CMAP)以及英国哈得来中心海表温度月平均资料,采用2009年Kao等定义的中部型ENSO指数,给出了夏季中部型海表温度(SST)异常指数,并分析了中部型ENSO和海洋性大陆(MC)区域气候的联系。结果表明,当夏季中部型海表温度正异常事件发生时,海洋性大陆核心区域(中太平洋)出现显著降水和气温负(正)异常,此时海洋性大陆核心区域有明显的负(正)热源异常,大气受冷却(加热)而下沉(上升),同时潜热释放之外的非绝热加热表现为负(正)异常,易于导致降水负(正)异常。海洋性大陆区域与中太平洋间主要通过水平环流和垂直环流建立联系。(1)中部型ENSO指数显著正异常时,在对流层低(高)层,海洋性大陆区域和中太平洋间存在由关于赤道的对称气旋性(反气旋性)环流对而形成的直接联系,并使得海洋性大陆区域东部辐散(辐合)偏弱,而海洋性大陆区域西部辐散(辐合)偏强。(2)在垂直剖面上,赤道中太平洋海表温度的正异常和海洋性大陆核心区域的大气异常冷却有利于促使该地区低层赤道西风异常增强并进而利于中部型海表温度正异常的维持,并由此通过反沃克环流圈促进海洋性大陆区域下沉运动增强。此为海洋性大陆与中太平洋间的直接联系,可由皮叶克尼斯机制进行解释。而位于中太平洋与秘鲁地区的异常垂直环流亦可用这一机制进行解释。海洋性大陆与中太平洋的间接联系主要表现在由赤道外低纬和中纬度地区均存在的沿弧形路径上的垂直环流而建立的海洋性大陆与中太平洋地区的联系上。这些弧形垂直剖面上的垂直环流不仅与局地哈得来环流有关,还与热带和中纬度的罗斯贝波动有关。这些结果有利于深刻认识中部型ENSO对海洋性大陆区域气候的影响机理以及与热带外环流异常的联系。  相似文献   
72.
Marine ecosystems provide a wide range of goods and services that directly and indirectly benefit economies and support human health and wellbeing. However, these ecosystems are vulnerable to anthropogenic influences such as climate change, pollution and habitat destruction. The European Union (EU) recognises the role of the blue economy in providing jobs and contributing to economic growth, with the EU Integrated Maritime Policy being a cross-sectoral framework within which maritime activities are managed and coordinated. Sustainability is a central tenet, ensuring that sectors such as aquaculture and offshore wind energy, which are earmarked for growth, must develop in ways that do not negatively impact the health of the marine environment. However, there is currently little consideration of how these activities might impact public health. The current research used survey data from 14 European countries to explore public perceptions of these issues, broadly focusing on 10 maritime activities, with a specific focus on five activities related to the EU’s 2012 Blue Growth Strategy. The respondents appreciated the interconnections between these maritime activities, environmental protection and public health, as well as the potential trade-offs. Preferences for policy intervention to protect public health from different activities were predicted by both marine contact (marine sector employment, recreational activities) and socio-demographic (political attitudes, gender, age) variables, potentially aiding future engagement and communication initiatives. Substantive differences observed across countries in terms of policy preferences for different activities, however, warn against generalising for the European population as a whole.  相似文献   
73.
The decline of the British shipping industry has had a significant impact on those sectors of the UK economy which have traditionally relied on ex-seafarers as a source of skilled labour. An in-depth study of the impacts of this problem was undertaken in 2003 to consider the implications of developments which have taken place in the industry since 1996. The UK economy's requirement for people with seafaring experience to fill land-based jobs was assessed, together with the implications of any shortfall. This paper considers the demand aspects of changes which have occurred since 1996.  相似文献   
74.
People with seafaring experience and skills are employed in the maritime sector of the UK economy in land-based jobs as well as in seagoing ones. This paper examines the balance of supply and demand in the land-based jobs market. It then considers the likely effects of a shortfall in the supply of British ships’ officers to fill net vacancies in jobs ashore, including the policy implications of this and the consequences for the economy's maritime skills base if the Government fails to act decisively now to correct market failure.  相似文献   
75.
In September 1997, the International Maritime Organization (IMO) adopted an international convention protocol to reduce air pollution from ships, in order to achieve sustainable maritime development. This protocol has been approved by 15 member countries and will be enforced in May 2005. Pollutants emitted from ships, such as nitrogen oxides, volatile organic compounds, sulfur oxides, etc. will be regulated by this convention through ship inspections and issuance of certificates. Ships belonging to maritime countries such as Taiwan, which sail around the world and berth in commercial ports, must obey this convention. This study has investigated possible strategies, which may be adopted by maritime countries to conform to this IMO convention in order to reduce the air pollution from ships. A sea-going ship must prepare EIAPP and IAPP certificates for inspection by port-state-control officials, when the ship is anchored at a maritime port. These port-state-control officials may also require the continuous detection and sampling of a ship's emissions, while it is berthed at the port. Legislative support is necessary for successful implementation of these safeguards. It is suggested, therefore, that the administration of both navigational and environmental protection, in maritime countries, cooperate in the revision of relevant federal laws, to implement the provisions of the MARPOL 73/78/97 convention; in this way, the air pollution from ships can be effectively controlled. Installation of advanced detection equipment can effectively detect any ships’ violations of air pollution regulations. The Harbor Affairs’ Bureau should also establish a database of air pollution inspections for ships berthed within their harbor, requiring that ships’ equipment comply with the requirements of the MARPOL convention, for the reduction of air pollution.  相似文献   
76.
2013年长江中下游地区夏季高温事件的环流特征及成因   总被引:2,自引:2,他引:0  
夏扬  徐海明 《气象科学》2017,37(1):60-69
采用ERA-interim和NCEP CFSR逐日再分析资料以及长江中下游29个测站的逐日温度资料,分析了2013年7月23日-8月14日长江中下游地区夏季异常高温的特点、环流特征及成因。研究结果表明,2013年夏季高温期间西太平洋副热带高压较往年异常偏强,西太平洋副热带高压控制区内大范围异常下沉运动产生的大气绝热加热是高温形成的主要原因。同时,与强大西太平洋副热带高压相联系的异常强大反气旋环流使得长江中下游地区上空的水汽向东北方向大量输出,导致了该区域水汽含量的减少,致使到达地面的太阳短波辐射增加,这是高温形成的又一原因。进一步分析表明,2013年夏季海洋性大陆地区大气热源异常偏强,该地区大气热源的异常增强可能是导致2013年夏季西太平洋副热带高压异常偏强的主要原因。  相似文献   
77.
为解决传统海运产业统计方法数据质量不高、时效性差、统计产品陈旧短缺、公信力不足等的问题,提出基于AIS大数据挖掘分析开展海运统计的方法.详细阐述了基于AIS大数据的海运统计分析技术路线、大数据平台技术架构,以及电子围栏分析、航行事件分析、航次分析和统计指标生成等关键模型算法.以2019年3月至5月全球大宗货品船舶的AIS数据应用为例表明,该方法可提供港口、海上通道和大宗货品三方面的海运大数据统计指标,为实现海运即时化、准确化、精细化的统计分析与展现提供了新思路.  相似文献   
78.
当前海警机构在海上遂行任务时面临多种形式的海上安全威胁,除常规安全威胁外,以海上军事冲突威胁和海上恐怖主义威胁为代表的非常规安全威胁正使海警面临越发严峻的海上综合实战能力考验。文章通过对海警视域下海上安全威胁的综合分析,提出提升装备体系化建设水平、增强人员实战化训练效果和探索海警多能化发展模式等应对策略,以期为海警未来妥善应对各类海上安全威胁及风险挑战提供有益参考。  相似文献   
79.
In 2007 the EU Commission published the so-called “Blue Book” aimed at developing an Integrated Maritime Policy for the Union. Even though Norway is not an EU member and is usually referred to as a small state, this article shows how the Norwegian government was able to exercise significant influence on EU maritime policy development, positioning itself as one of the key actors. Applying the negotiation theory and tracing the process as it unfolded, this analysis identifies causal relationships leading to increased influence for Norwegian actors—particularly in respect to how issues concerning the Arctic became an integrated part of the policy. The paper concludes that even though the Norwegian actors had a strategic point of departure, utilizing objective advantages to maximize their own utility, their influence may also have been due to competence and sharing of knowledge. The article relies on official documents, but is to a large extent also based on interviews with key EU Commission and Norwegian governmental representatives. On an elevated, substantive analytical level the article contributes to the “small state” research agenda and its interest in how small states in international relations might influence policy outcomes and thrive in the international community.  相似文献   
80.
The article takes as its point of departure the apparently contradictory findings in recent research about accident rates in shipping and IMO implementation records. It is argued here that although IMO conventions have probably greatly improved shipping safety, they cannot credibly be held to be the chief cause of reduced accident rates as claimed in a recent Marine Policy article, when the documented failures of flag state and port state implementation continue to leave vessels sailing with grave deficiencies. The present analysis posits and corroborates a cluster of linked tendencies that jointly undermine IMO implementation. The core problem is IMO’s weak connection to the national maritime administrations, leading to broadly discretionary practices, exacerbated by language difficulties. Adding new rules is no panacea, as new rules in some cases negatively affect the functioning of existing regulations, and sometimes seem motivated mainly to show political alertness. The structural weakness of the IMO/member state link is the core implementation problem that urgently needs to be dealt with if marine safety is to be improved. The concluding section proposes a reform to bring the IMO out of this conundrum and ensure effective implementation.  相似文献   
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