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1.
When two industries make competing claims to exploit resources in the same geographic area, conflicts may arise. While a substantial literature deals with the resolution of such conflicts between industrial interests and environmental conservation, the research on successful resolution of coastal industry-industry conflicts is limited. As noted by [45], “the emerging field of coastal conflict research has no clear contours. It develops from different disciplines, theories, approaches, practical knowledge requirements, and does not become, as far as can be foreseen, a fully integrated knowledge field…in-depth analysis of conflicts and empirically based approaches to conflict resolutions are hardly found”. This article fills some of these knowledge gaps by empirically analysing how and to what extent the Norwegian regime governing the relationship between the oil and fishery industries along the Norwegian coast helps reduce conflict levels and resolve the conflicts that nevertheless arise. The article builds on both regime theory and conflict resolution theory to analyse its institutional design and effects, posing two research questions: First, what is the institutional design of the Norwegian oil and fisheries coexistence regime? Second: to what extent does the regime reduce the conflict potential and contribute towards conflict resolution?  相似文献   

2.
A global recurring challenge for marine managers and policy makers is the effective management of fisheries conflicts. This study demonstrates the usefulness of a political ecology approach in understanding the complexity of conflict in increasingly internationalized national fisheries. By doing so it aims to provide an alternative approach to the environmental security perspectives, predicated on scarcity narratives, that often underpin policy on fishery conflicts. Using a localised example of industrial Chinese and local artisanal fishermen conflict in Ghana, this paper reveals a complex account of contesting ‘access’ to resources, in material and nonmaterial terms, that moves beyond an ‘absolute scarcity’ driven narrative. The conflict is shown to be one, in part, focussed around spatially fixed areas as well as moral claims of correct ways of fishing that reflect social tensions within the local fishing community. Both aspects show long term motivations to keep resource access, rather than being concerned with in the moment struggles over scarce resources. This work also highlights the existence of cooperation between groups of artisanal fishermen involved in transhipment with Chinese fishermen, revealing the complex nexus of winners and losers produced by environmental, social and political factors. In sum, policy must acknowledge that conflict is rarely produced purely by scarcity, and that broader social and political factors often combine in a variety of forms to produce localised conflict. If these complexities are ignored, fisheries policy runs the risk of unintentionally exacerbating conflicts and disadvantaging those who it aims to help.  相似文献   

3.
Interdecadal Pacific variability (IPV) is commonly observed in both the tropical and mid-latitude Pacific Ocean, and has a widespread influence on surface climate in the Pan-Pacific Basin. This variability is recorded by climate proxies such as geochemical parameters preserved in corals. However, the origins of IPV remain uncertain. To shed light on this, interdecadal variations in two long coral δ18O records from Nauru Island and the South China Sea (SCS), respectively located in the tropical Pacific and the mid-latitude North Pacific Ocean, were investigated. The interdecadal fluctuations in the δ18O series from Nauru Island (tropical Pacific) match those of the NINO3.4 index reasonably well (r=–0.30, n=96, p=0.0015), but are not correlated with those of the Pacific decadal oscillation (PDO) index (r=–0.17, n=96, p=0.05). The δ18O time series from the SCS (northwestern Pacific), by contrast, co-vary with the PDO index (r=–0.30, n=156, p=0.0007), but are out of phase with the NINO3.4 index at the interdecadal timescale (r=0.04, n=156, p=0.31). The impact on the interdecadal variability of processes occurring outside the growth region of corals is generally weak. The results thus do not support a tropical origin of IPV, but demonstrate that the interdecadal variability in the tropical Pacific and the North Pacific originates predominantly from local coupled ocean–atmosphere processes within these regions. The results also suggest that tropical–extratropical interactions played a role in IPV between 1920 and 1940, which indicates that IPV is a complex climatic phenomenon that involves multiple forcing mechanisms.  相似文献   

4.
Based on the 45-year (09/1957-08/2008) European Centre for Medium-Range Weather Forecasts (ECMWF) Reanalysis (ERA-40) wave reanalysis dataset, this study analyzes interannual and interdecadal variabilities and intraseasonal oscillations of sea surface wind speed (WS), wind sea wave height (Hw), swell wave height (Hs) and significant wave height (Hs) in the Roaring Forties and tropical waters of the Indian Ocean, to determine swell propagation characteristics. The results show: (1) monthly variabilities of Hs in the Roaring Forties are in good agreement with those in tropical waters of the Indian Ocean; swell plays a dominant role in mixed waves throughout most of the Indian Ocean; and WS, Hw, Hs, and Hs exhibit a significant increasing trend over the 45-year study period. (2) Hs in the Roaring Forties and tropical waters of the Indian Ocean share a common period of 9.8–10.4 years on an interdecadal scale; and WS and Hs in the Roaring Forties and Hs in the tropical waters of the Indian Ocean share a common period of approximately 8 days (weekly oscillation) on an intraseasonal scale. (3) Swell of the Roaring Forties needs approximately 30 h to fully respond to the wind in this region. Approximately 84 h are required for Hs to propagate from the Roaring Forties to the tropical waters of the south Indian Ocean, while it takes approximately 132–138 h for Hs to propagate from the Roaring Forties to the tropical waters of the north Indian Ocean.  相似文献   

5.
In this study, we use existing observational datasets to evaluate 20th century climate simulations of the tropical Pacific. The emphasis of our work is decadal variability of the shallow meridional overturning circulation, which links the tropical and subtropical Pacific Ocean. In observations, this circulation is characterized by equatorward geostrophic volume transport convergence in the interior ocean pycnocline across 9°N and 9°S. Historical hydrographic data indicate that there has been a decreasing trend in this convergence over the period 1953–2001 of about 11 Sverdrup (1 Sv = 106 m3 s−1), with maximum decade-to-decade variations of 7–11 Sv. The transport time series is highly anti-correlated with sea surface temperature (SST) anomalies in the central and eastern tropical Pacific, implying that variations in meridional overturning circulation are directly linked to decadal variability and trends in tropical SST. These relationships are explored in 18 model simulations of 20th century climate from 14 state-of-the-art coupled climate models. Significant correlation exists between meridional volume transport convergence and tropical SST in the majority of the models over the last half century. However, the magnitude of transport variability on decadal time scales in the models is underestimated while at the same time modeled SST variations are more sensitive to that transport variability than in the observations. The effects of the meridional overturning circulation on SST trends in most the models is less clear. Most models show no trend in meridional transport convergence and underestimate the trend in eastern tropical Pacific SST. The eddy permitting MIROCH model is the only model that reasonably reproduces the observed trends in transport convergence, tropical Pacific SST, and SST gradient along the equator over the last half century. If the observed trends and those simulated in the MIROCH model are ultimately related to greenhouse gas forcing, these results suggest that the Bjerknes feedback, by affecting pycnocline transport convergences, may enhance warming that arises from anthropogenic forcing in the eastern tropical Pacific.  相似文献   

6.
This paper uses spatial, temporal, and use-intensity data for 27 major marine uses in Washington waters to feature a method for assessing potential use conflicts in a variety of scenarios. The study represents a first step towards quantifying potential conflicts within Washington’s Marine Spatial Planning (MSP) study area by using a cumulative analysis to highlight high- and low-use intensity areas and the novel Marine Potential Conflict Index (MPCI), which incorporates space, time, and intensity of use, to quantify pairwise potential conflicts between uses. About 10% of pairs of uses do not overlap spatially and are likely compatible with one another. Temporally, the number of uses peaks in July and August and falls during January and February. Additionally, the MPCI identified three important use types with a substantial degree of potential conflict: commercial fishing, tribal fishing, and shipping. External data were used in three cases to ground-truth the analysis, as a limited test of its utility in managing any potential conflict. This article assesses the extent of Washington’s existing marine uses along spatial, temporal, and intensity axes, and more broadly provides a straightforward way to examine potential conflicts between marine uses.  相似文献   

7.
2008年南海季风爆发前后西沙海域海气通量变化特征   总被引：4，自引：1，他引：3  
基于2008年4至5月在南海西沙永兴岛进行的海气通量观测试验资料和NCEP资料,应用COARE3.0通量算法计算了海气通量,分析了季风爆发前后西沙海域天气变化特点和海气通量对南海季风爆发的响应。结果表明:2008年南海季风首先于5月第1候在南海南部爆发,受热带气旋等因素的影响,北部海区季风爆发推迟到5月18日。季风爆发和热带气旋活动对西沙海域的风速和海气通量影响较大,其中热带气旋的影响更强烈。热带气旋来临之前,潜热通量、感热通量以及动量通量均较小;在气旋活动及此后的季风爆发时期,大风使潜热通量和动量通量显著增强,感热通量则在降水期间变化明显;动量通量的最大值出现在热带气旋活动期间,其在此过程中的均值是观测初期均值的3倍以上。在整个观测过程中,潜热通量明显大于感热通量,后者是前者的16∶1。不同类型天气过程中,潜热通量的日变化相似,而感热通量的日变化有差异。湍流交换系数与风速有较好的相关关系。  相似文献   

8.
Oceanographic data from the regional data bank, covering a period from 1911 through to 1990, in combination with the climatic tangential wind stress data have been applied to determine the historical fields of summary currents in the north-western tropical Atlantic; currents of the major circulation elements in the active layer have been specified. It has been confirmed that a significant, in terms of climate, transport of surface and subsurface waters by the geostrophic component of the North Brazil current (NBC) to the northern tropical Atlantic does not take place. North-west of 2oN and 45o W, the current turns eastward, thus contributing to the generation of the equatorial countercurrent. The transport of the NBC within a 0–500 m layer near 1o N has been evaluated to be equivalent to 50 Sv, and the mean annual transport of the equatorial countercurrent to 30 Sv. Translated by Vladimir A. Puchkin.  相似文献   

9.
20世纪50年代以来登陆中国热带气旋的变化特征分析   总被引：1，自引：0，他引：1  
基于1951—2017年西北太平洋热带气旋路径资料,利用趋势分析、R/S分析以及周期分析等方法对近67年来登陆中国热带气旋的个数、频次、强度以及登陆位置等热带气旋活动特征进行深入分析,结果表明:(1)近67年登陆中国热带气旋的个数和频次均呈下降趋势,下降幅度分别为0.003个/a和0.008次/a,但变化趋势均不显著,未来一段时期热带气旋登陆个数、频次将呈缓慢增加趋势。(2) 6—10月是热带气旋发生和登陆的高频期,其中,8月份热带气旋的发生次数和登陆中国的次数均最多。(3)历年最低中心气压、平均中心气压均呈增加趋势,且最低中心气压通过了M-K显著性检验;热带气旋登陆强度总体呈减弱趋势,且未来一段时期将继续呈减弱趋势,但高强度热带气旋呈显著增加趋势。(4)广东、台湾、海南、福建和浙江是热带气旋的主要登陆地;热带气旋的登陆位置呈向东、向北偏移趋势,且未来时期该偏移趋势仍将持续。利用热带气旋路径数据分析1951—2017年登陆中国热带气旋的数量、强度等变化,旨在深入认识影响中国的热带气旋活动的特征及规律,为热带气旋的预报、预警及防灾减灾工作等提供科学参考。  相似文献   

10.
本项研究试图从沉积记录中分析古风暴事件的时间序列。以海南岛东南部黎安潟湖和新村潟湖钻孔沉积物为研究对象,选取沉积物粒度、有机质和碳酸盐含量等参数建立台风事件的鉴别指标,同时利用放射性核素210Pb计年确定沉积物柱状样的年代序列,对海南岛东南部的古风暴活动进行了分析。结果显示,柱状岩心的粒度指标、有机质和碳酸盐含量清晰地记录了海南省东南部过去350年期间的35次特大风暴潮事件,与历史文献资料对比良好。基于历史文献和沉积记录的风暴潮事件恢复了近350年来的风暴活动历史,发现海南省东南部特大风暴事件频数与厄尔尼诺强度有显著关系,同时还可能受到太平洋涛动和太阳黑子活动等多种因素的综合影响。恢复海岸带地区长时间尺度高分辨率的古风暴记录,为探讨全新世以来古风暴活动的气候响应机制提供了有效信息。  相似文献   

11.
The characteristics of waves, winds and currents in a tropical cyclone environment differ significantly from those in a winter storm environment, like the North Sea. This can have a significant effect on the reliability of a mooring system that is designed to satisfy 100 yr conditions with specified Factors of Safety in accordance with ISO19901-7 or API RP 2SK. This paper presents reliability analysis of the mooring system of a permanently connected Floating LNG vessel, placed at two locations: (a) a tropical cyclone environment of the North West Shelf of Australia and (b) a winter storm environment of the North Sea. It is demonstrated that as a result of differences in the long term distribution of environmental parameters (waves, winds) between a North Sea environment and a tropical cyclone environment, the long term distribution of the mooring line response differs significantly in these two locations.This paper shows that a mooring system which is designed in accordance with ISO (or API), in these two environments, will achieve very different reliability levels because of the significant differences in environmental characteristics. In order to achieve the same reliability for the mooring system at these two geographical locations, Factors of Safety for use with 100 yr environmental conditions (Ultimate Limit State) were derived to achieve the same target probability of failure of 10−4/annum. It was found that for the North Sea environment, a factor of 1.5 is required for both the mooring chain and the pile, while for the tropical cyclone environment the required Factor of Safety has to be increased to 2.1. These differences are very significant and design standards need to be revised to reflect these findings.  相似文献   

12.
The choice of a characteristic magnitude in an earlier article by Lee and Veronis [1991. On the difference between tracer and geostrophic velocities obtained from the C-SALT data. Deep-Sea Research 38, 555–568], using inverse methods on the C-SALT data was based on an inappropriate velocity. As a result, the estimated magnitudes of the vertical diffusivities resulting from salt fingers were too large. The present paper corrects that error and yields a vertical diffusivity for salinity of 0.89×10−4 m2/s, which is consistent with a value derived from a tracer release experiment [Schmitt et al., 2005. Enhanced diapycnal mixing by salt fingers in the thermocline of the tropical Atlantic. Science 308, 685–688].  相似文献   

13.
The Shuttle Radar Topography Mission (SRTM) provided an unprecedented source of space-borne topographic information that has shown to be of particular interest for studies in densely vegetated tropical areas, such as Central Amazonia. The digital elevation models produced in that region show subtle details of the terrain that usually appear blurred in conventional remote sensing images. Interpretation of an SRTM-derived drainage network and geomorphometric features revealed several drainage anomalies, which are possibly the surface expression of buried morphostructural features. Integration with geological and geophysical ancillary data strongly suggested that interpreted features constitute potential structural sites for hydrocarbon exploration. However, due to their inferred nature, the structures herein identified are not by themselves a justification for drilling. However, they do provide information for planning seismic surveys, thus reducing costs of the exploration campaigns, as well as minimizing potential environmental impacts of such an enterprise in areas of tropical rain forests. Despite the relatively small size of the study area, it is expected that procedures presented in this paper can be successfully applied throughout the approximately 1,000,000 km2 of sedimentary basins in the Brazilian Amazonian region.  相似文献   

14.
This article examines current neoliberal forces in the Torres Strait tropical rock lobster (TRL) fishery and their likely impacts on the lives of indigenous Islanders. It describes how neoliberal principles of market governance, commodification of natural resources, profit maximization, individualization and property rights are at odds with Islander rights, values, sense of place, and institutions of knowledge, tenure and practice. It argues that proposed fisheries measures based on neoliberal imperatives could cause important conflicts and create high social, political, and economic costs. The TRL fishery is integral to Islanders’ aspiration of self-determination and economic autonomy. A more holistic vision inclusive of Islander perspectives is necessary if management of the TRL fishery is to be truly socially and culturally appropriate.  相似文献   

15.
热带太平洋是金枪鱼类、旗鱼类等渔业的主要作业海域，但目前针对此海域食物网的研究仍十分缺乏。本文根据2017年6月-11月中国金枪鱼科学观察员在热带太平洋中东部海域（13°09''N -34°27''S, 100°03''-176°17''W）采集的鱼类样品，结合胃含物及其他分析方法以35个物种间的摄食关系为基础对此海域的食物网结构进行了分析。拓扑学指标（节点强度，D；中心性指数，BC和CC；拓扑重要性指数，TI1和TI3；关键性指数，K、Kt和Kb）和Key-Player算法（KPP-1和KPP-2）用来筛选关键种，并结合体长数据建立了基于关键种的简化食物网。肯德尔相关性分析和聚类分析结果表明，不同拓扑学指标筛选出的关键种是一致的。大多数关键种与太平洋其他海域的研究结果是相同的，如剑鱼（Xiphias gladius）、长鳍金枪鱼（Thunnus alalunga）、小吻四鳍旗鱼（Tetrapturus angustirostris）头足类和鲭属。移除5个关键种后，食物网将被离散为许多互不连接的部分（F=0.632，FD=0.795，RD=0.957），表明这些物种在维持食物网结构和稳定性中的必要性。物种体长是本研究构建简化食物网时的决定性因素。研究结果有助于提高对热带太平洋食物网结构的认识，同时为进一步的生态系统动力学研究提供科学依据。  相似文献   

16.
An estimate of Atlantic Ocean thermal energy conversion (OTEC) resources   总被引：1，自引：0，他引：1  
Grard C. Nihous 《Ocean Engineering》2007,34(17-18):2210-2221
An interhemispheric box model of the Atlantic thermohaline circulation (THC) is modified by replacing the tropical box with two vertically resolved sub-domains. Seawater flows from large-scale ocean thermal energy conversion (OTEC) are allowed in one of the tropical sub-domains. Under present conditions and standardized OTEC operations, steady-state net power production density would reach a maximum of about 80 kW/km2 (corresponding to 1.8 TW) with a cold seawater withdrawal per unit area of about 14 m/yr. This maximum reflects the impact of large OTEC flows on the oceanic thermal structure, although the THC would not be significantly affected. It is larger than a recently suggested worldwide value of the order of 30 kW/km2 because of the relative strength of the Atlantic THC. Under asymmetric high-latitude warming scenarios potentially representative of current climatic trends, a substantial weakening or a reversal of the THC are possible. In the former case, recoverable OTEC resources could practically vanish. In the latter case, the emergence of a stronger reverse THC eventually could boost OTEC resources. Such events are hypothetical and would unfold over centuries, but the mere possibility of their occurrence challenges the accepted notion that OTEC resources are forever renewable.  相似文献   

17.
One of the major dilemmas of using rural commons for industrial uses in developing countries relates to the failure of the state to evolve consensus on allocating property rights to local communities and modern enterprises in a manner that sustains livelihoods and ecosystems. While traditional coastal communities enforce customary rights for fishing and mineral mining, the state sometimes reallocates traditional fishing territories to commercial mining to facilitate rapid industrialization. Communities oppose such transfers because of the negative impacts of commercial dredging on traditional fishing and ecosystems. Based on detailed field level surveys conducted in 2004, this paper describes how rural island communities along Cochin estuary expressed their opposition to the transfer of clam-mining rights to industries by democratic social mobilization. Counter moves were collectively organized by modern enterprises and trade unions which had the support of the state. However, major political parties retreated from conflict management, leaving the matter in a state of flux. This paper suggests that the state must recognize traditional livelihood rights of communities if it is to resolve conflicts and ensure the sustainable and equitable use of natural resources.  相似文献   

18.
Marine protected areas created in a top-down way can be costly and ineffective due to low compliance of resource users. Conversely, employing users’ local knowledge and involving them in decision-making processes could decrease costs and conflicts, in addition to increasing the chances of management success. Here the potential to change conflicting MPAs into conservation areas that take into account fishers’ use and knowledge is assessed based on a case study on the Brazilian coast (Paraty town). Fishers (n=206) from 11 villages were interviewed regarding their main fishing targets and gear, and then only the experienced ones (n=41) were interviewed from three main fishing villages about the most important commercial species. Fish landings were sampled for one year in these three villages (n=823), where participatory mapping and group interviews with fishers were also conducted to determine their opinions regarding management and how they thought it should be undertaken. Management measures should not be equivalent across the whole region, as there were clear differences in the target species and gear used. Fishers identified 55 important fishing spots, eight of which were important for more than five villages, while the experts identified 10 important fishing areas for the target species, which was supported by the sampling of fish landings. The fishers were not opposed to management and no-take reserves but would make some changes in the current design of these measures if it were up to them. Based on these data, a few changes were indicated in the design of these areas that would likely reduce the conflict between fishers and enforcement agencies. This kind of approach could be used as a framework for adapting conflictive MPAs or to support the establishment of new ones where fisheries are relevant.  相似文献   

19.
Bacterial productivity (BP) and respiration (BR) were examined in relation to primary productivity (PP) for the first time in a shallow tropical ecosystem (Cochin Estuary), India. The degree of dependence of BP (6.3–199.7 μg C L−1 d−1) and BR (6.6–430.4 μg C L−1 d−1) on PP (2.1–608.0 μg C L−1 d−1) was found to be extremely weak. The BP/PP (0.05–8.5) and PP/BR (0.02–7.9) ratios widely varied in the estuary depending on the season and location. There was a seasonal shift in net pelagic production from autotrophy to heterotrophy due to terrestrial organic matter input through rivers which enhanced the bacterial heterotrophic activity and very high pCO2 (106–6001 μatm) levels. The heterotrophic zones were characterized by low PP but high bacterial production and respiration leading to oxygen undersaturation and exceptionally high pCO2. We propose that the CO2 supersaturation caused by increased bacterial respiration (in excess of PP) was a result of bacterial degradation of allochthonous organic matter. This indicates that sources other than planktonic compartment need to be explored to understand the C-cycling in this estuary. These results are of particular relevance to tropical ecosystems in general, where the bulk of world's river discharges occur.  相似文献   

20.
Mesoscale eddies and tropical instability waves in the eastern tropical Pacific, first revealed by satellite infrared imagery, play an important role in the dynamics and biology of the region, and in the transfer of mass, energy, heat, and biological constituents from the shelf to the deep ocean and across the equatorial currents.From boreal late autumn to early spring, four to 18 cyclonic or anticyclonic eddies are formed off the coastal region between southern Mexico and Panama. The anticyclonic gyres, which tend to be larger and last longer than the cyclonic ones, are the best studied: they typically are 180–500 km in diameter, depress the pycnocline from 60 to 145 m at the eddy center, have swirl speeds in excess of 1 m s−1, migrate west at velocities ranging from 11 to 19 cm s−1 (with a slight southward component), and maintain a height signature of up to 30 cm. The primary generating agents for these eddies are the strong, intermittent wind jets that blow across the isthmus of Tehuantepec in Mexico, the lake district in Nicaragua and Costa Rica, and the Panama canal. Other proposed eddy-generating mechanisms are the conservation of vorticity as the North Equatorial Counter Current (NECC) turns north on reaching America, and the instability of coastally trapped waves/currents.Tropical Instability Waves (TIWs) are perturbations in the SST fronts on either side of the equatorial cold tongue. They produce SST variations on the order of 1–2 °C, have periods of 20–40 days, wavelengths of 1000–2000 km, phase speeds of around 0.5 m s−1 and propagate westward both north and south of the Equator. The Tropical Instability Vortices (TIVs) are a train of westward-propagating anticyclonic eddies associated with the TIWs. They exhibit eddy currents exceeding 1.3 m s−1, a westward phase propagation speed between 30 and 40 km d−1, a signature above the pycnocline, and eastward energy propagation. Like the TIWs, they result from the latitudinal barotropically unstable shear between the South Equatorial Current (SEC) and the NECC with a potential secondary source of energy from baroclinic instability of the vertical shear with the Equatorial Undercurrent (EUC).This review of mesoscale processes is part of a comprehensive review of the oceanography of the eastern tropical Pacific Ocean.  相似文献   

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