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1.
By using the NCEP/NCAR reanalysis data sets for 1951–2001, we study the characteristics of Pacific cyclones. It is shown that the northeast-southwest direction is predominant in the displacements of cyclones in the North Pacific. We study the variability of the field of surface atmospheric pressure in different phases of the Pacific decadal oscillation characterizing the temperature anomalies on the surface of the ocean in the region bounded by 20 and 60°N. It is shown that the decadal variations of the North Atlantic Oscillation supported by the large-scale anomalies of the Pacific decadal oscillation is the most important cause of natural decadal oscillations in the European region. We study and evaluate the regional response to the Pacific decadal oscillation by using, as an example, the analysis of variations of the discharge of European rivers. __________ Translated from Morskoi Gidrofizicheskii Zhurnal, No. 4, pp. 13–23, July–August, 2007.  相似文献   

2.
本文初步概述饲养欧洲鳗鲡(Anguillaanguilla)的食性特征,对蛋白质的表现消化率和日粮蛋白质的需求量、驯饵、饲料形态、给饲率以及实用的欧鳗配合饲料。建议采用膨化颗粒饲料,制订欧级饲料实验方法和条件的规范。  相似文献   

3.
Published and original data on the lithology and fauna (mainly foraminifers) of the Paleogene Norwegian-Greenland and Northwestern European Sea Basins are generalized in this article. Their paleogeographic evolution and the character of development of connections with the North Atlantic, Mesotetis, and the Arctic Ocean are established from the moment of generation to their disappearance. It is shown that the paleogeographic conditions of the studied sedimentation basins depend to a great extent on the tectonic movements of lithospheric plates. Iceland Plume volcanism exerted a considerable influence on the paleoenvironment and sedimentogenesis. The paleotectonic and climatic conditions of sedimentation are reconstructed. The occurrence of bauxite-bearing continental residual soil and other data point to a tropical, humid climate in the Early Paleogene, which changed into a moderate humid climate by the end of the Late Paleogene. Terrigenous sediments, including oil-and-gas bearing ones, were formed in the sea basins; they contain products of eroded residual soil, placers of accessory minerals, pyroclastics of volcanoes of the Iceland Plume, and zeolite-bearing, amber-bearing, phosphorite-bearing, and glauconitic horizons that have practical interest.  相似文献   

4.
Computer-assisted analyses of more than 600 radiocarbon-dated sea-level indicators from northwestern Europe, concentrated around the North Sea margin, indicate that vertical crustal movements are more important that eustatic sea-level change in determining the locus of Holocene shoreline positions through time. For the past 14,000 radiocarbon years, the divergence of sea-level data for the northwest European sectors exceeds the maximum estimated sea-level rise by a factor of two or more. Projecting these data to a single meridian demonstrates the remarkable variety of vertical crustal movement in northwestern Europe.Accumulating radiocarbon-dated sea-level indicators into millennial cohorts, we generate isobase maps which begin to specify areas of notable vertical crustal mobility. These isobase maps appear to confirm that eustatic sea-level rise is subordinate to postglacial geoidal excursions in determining the locus of contemporary northwestern European shorelines.  相似文献   

5.
In the period 1983-2007, The European Union controlled the evolution of the capacity of its fishing fleet through the so-called Multi-Annual Guidance Programmes (MAGPs). As a result, The European Union reduced the number of fishermen, fishing vessels, gross tonnage and power. However, the end of this period saw an increase in the average size of the fishing vessel and a reduction in crew size. The new “average fishing-vessel” was a more technologically advanced vessel with a greater fishing capacity and a higher degree of autonomy. The aim of the study presented here is to determine the degree of inequality to be found between the fishing capacities of the fleets of the European Union, and to verify whether the evolution of the “average fishing-vessel” responds to a homogenous trend shared by all of the fishing fleets of the European Union or whether it is in fact more unequal. The study formalises a methodology, using Theil indices, which enables the inequalities found between the capacities of the fishing fleets during the period of application of the MAGP adjustment polices to be analysed. The study uses data on fishermen, boats and tonnages from 13 countries of the European Union and results are obtained for the inequality indices of the average size of the fishing vessels, their degree of technological advance and their average crews.  相似文献   

6.
Gridding and merging of onshore gravity and topography information from the British National Gravity and Topography Data Bank with offshore free-air gravity anomalies derived from SEASAT altimeter data and bathymetry from the National Geophysical Data Center (USA) has allowed, for the first time, the production of digital images for the north-western European continent and shelf (48°–62° lat., 348°-010° long.). Further, using image processing techniques, the images have been selectively filtered (using artificial illumination) to enhance both Caledonian and Variscan trends. As a large amount of terrestrially-acquired offshore gravity data already exists within the North Sea region, it has been possible to test the accuracy of the SEASAT derived free-air gravity anomaly data. Hence its use in geological and geophysical interpretations, by comparing the two. We conclude that while the derived (SEASAT) gravity trends are essentially correct, significant error may exist in the amplitude determination, especially where anomaly wavelengths are short and oceanographic components in the altimeter data are significant. The potential value of ‘geotectonic images’ is as an aid in recognising trends and relationships between geological and/or tectonic domains that are not generally apparent in the more conventional representations of these data (e.g. profile and contour maps). We offer interpretations for both the local free-air/Bouguer gravity anomalies in terms of the known geology of the British Isles and offshore regions, and the regional gravity anomalies in terms of the thermal and mechanical response of the north-western European lithosphere during Variscan compression (continental collision and thrust-sheet migration) and Palaeozoic, Mesozoic, and Cenozoic rifting events (sedimentary basin formation).  相似文献   

7.
温彩霞  郑小宏  高其文 《台湾海峡》2001,20(Z1):169-171
用不同浓度的无机氮,以水浴和注射两种方法对正常欧鳗进行攻击,抽取其心脏血液测定电解质的变化,结果所有实验组的血氯离子均比正常组的低,下降幅度为20%~35%,"狂奔病"症欧鳗的血氯离子也比正常鱼的下降了20%~45%.警示欧鳗配合饲料蛋白质效率(PER)和给饲技术管理的重要性.  相似文献   

8.
Despite the importance of the socio-economic dimension of the use of marine waters, there has been little research in the field until recently, when interest has grown in the concept of ‘blue growth'. This paper aims to contribute to filling this gap with a socio-economic assessment of the main maritime sectors, focused on the Spanish part of the European Atlantic Arc. To this end, it first proposes a theoretical structure for the maritime economy and then collects and classifies comparable and reliable maritime socio-economic indicators. The data obtained allows us to assess the size of the Spanish maritime sector and the position of the Spanish Maritime Cluster in the wider context of the maritime economy of the European Atlantic, as well as discuss the appropriateness of a strategy of forming clusters at the national level vs. a transnational approach. The results indicate differences between regions in the European Atlantic Arc that complicate the development of integrated policies to stimulate blue growth. Extending our knowledge of the maritime economy of the European Atlantic Arc will make it possible to design strategies that address the real issues, increasing the likelihood of these being effective.  相似文献   

9.
A gridded monthly terrestrial precipitation from the Climatic Research Unit (CRU), University of East Anglia data set and the UK Met Office Northern Hemisphere mean sea level pressure data are used to investigate interdecadal changes in the relationships between precipitation variability over Europe and atmospheric circulation in the Atlantic–European sector during boreal spring and fall.
Singular value decomposition (SVD) analysis, performed for the climatic periods of strong/weak links to the North Atlantic Oscillation (NAO) during spring and fall, revealed considerable interdecadal changes both in the strength and the structure of the links between European precipitation and regional atmospheric circulation. During periods of strong links to the NAO, the leading SVD mode is characterized by the NAO-like meridional dipole in sea level pressure (SLP) fields and associated opposite precipitation variations over northern/southern Europe. When the links to the NAO are weak, the leading SVD mode is represented by the tripole pattern in SLP fields over the North Atlantic–European region, driving regional precipitation variability both in spring and fall. Further correlation analysis has shown that this mode is associated with the Scandinavian teleconnection pattern (SCA). Thus, for the considered seasons during periods of weak NAO influence, the SCA plays a role of major driver of the regional precipitation variability.  相似文献   

10.
The implementation of the Natura 2000 network of marine protected areas under the European Habitats Directive (92/43/EEC) has far-reaching implications for fisheries. To date, no consistent approaches have been established to develop fisheries management measures in Natura 2000 areas, and no European member state has proposed any fisheries measures to the European Commission for consideration under the Common Fisheries Policy. Four key issues are identified in the relationship between fisheries and Natura 2000, and the possible role that the future Common Fisheries Policy could have in this context is discussed. There is a need (1) for a consistent framework to integrate scientific advice, stakeholder participation and management in the management process; (2) for a common methodology to prioritize conservation objectives, in particular for transboundary protected areas; (3) for a consistent framework to assess and evaluate fisheries impacts to define management measures; and (4) to define spatial properties for fisheries. The results from the projects EMPAS (Germany), FIMPAS (the Netherlands), and INDEMARES (Spain) and the Dogger Bank case are discussed.  相似文献   

11.
The European principles of Integrated Coastal Zone Management (ICZM) are often viewed as central, defining features of the EC approach to ICZM, enshrined within the EC Recommendation (2002/413/EC) and endorsed by the European Commission in its Communication on ICZM (COM(2007) 308 final). This paper presents the findings of COREPOINT surveys which evaluated the extent to which the ICZM principles are addressed and interpreted across the North West European region. An interpretation of these findings is undertaken in order to provide an assessment of local ICZM development against the European ICZM Progress Indicator. The surveys revealed rather mixed adherence to with the EC ICZM principles at national, regional and local levels, although there were some promising results related to the principles of local specificity and stakeholder engagement. The principles providing the greatest challenge were those promoting the broad holistic approach, the long-term approach and adaptive management. The surveys demonstrated the value of using a structured, clearly designed ‘expert’ survey for providing an insight into operational aspects of the ICZM principles and provided a means of assessing ICZM progress. As such, this paper provides a useful contribution to the ongoing European and wider debate about the principles and their evaluation.  相似文献   

12.
《Marine Policy》2005,29(3):189-197
Within the European Union, scientific fisheries research and advice is passed down a chain of central European institutions before being incorporated into policy. However, advice is often poorly or only partially implemented and the system has largely failed to achieve sustainable fisheries management.This paper aims to explain why, by examining the use of fisheries science within the Common Fisheries Policy (CFP). The problem is examined with respect to both the political system and fisheries science, to show that the factors in both the supply, and the subsequent use, of scientific data inhibit effective fisheries management.  相似文献   

13.
Successive marine policies set by the European Union identify the maritime sectors as crucial drivers for growth and jobs in the EU economy. The design of marine policies and the assessment of the importance of the maritime economy need empirical support that provides the basic data to help the decision-making process. This paper proposes a metric, in the form of a synthetic index, to measure and compare the importance of the maritime sectors in the European Atlantic area. The index scores can be used to assess the position of each Atlantic region so that it is possible to compare its performance to the rest of the area. The results show the relative weight of the maritime sectors in the European Atlantic regions and the high heterogeneity among them. Analyzing the maritime economy with this index can provide guidance for the design of economic policies to identify and revitalize the regions with greater potential for Blue Growth in the Atlantic area. This may help to put into perspective the importance of the maritime economy and can serve to improve the socio-economic dimension of the use of marine waters.  相似文献   

14.
Extreme sea levels at European coasts and their changes over the twentieth and twenty-first centuries are considered, including a method to analyze extreme sea levels and to assess their changes in a consistent way at different sites. The approach is based on using a combination of statistical tools and dynamical modelling as well as observational data and scenarios for potential future developments. The analysis is made for both time series of extreme sea levels and individually for the different components contributing to the extremes comprising (i) mean sea level changes, (ii) wind waves and storm surges and (iii), for relevant places, river flows. It is found that while regionally results vary in detail, some general inferences can be obtained. In particular it is found, that extreme sea levels show pronounced short-term and long-term variability partly associated with seasonal and nodal tidal cycles. Long-term trends are mostly associated with corresponding mean sea level changes while changes in wave and storm surge climate mostly contribute to inter-annual and decadal variability, but do not show substantial long-term trends. It is expected that this situation will continue for the upcoming decades and that long-term variability dominates over long-term trends at least for the coming decades.  相似文献   

15.
Izvestiya, Atmospheric and Oceanic Physics - The smoke haze over the European part of Russia (EPR) and Belorus in July 2016 has been studied with the use of aerosol optical thickness (AOT) data...  相似文献   

16.
We study the water vapor (WV) content over European Russia (ER) during the period of forest and peatbog fires in July–August 2010 using total column water vapor observations from MODIS instruments (both Aqua and Terra platforms) as well as aerological data and NCEP/NCAR reanalysis. It is found that the spatial distribution of total column water vapor (TCWV) over ER in this period was anomalous, with the WV excess in the north of the territory and its deficit in the south of ER. The relationship between WV variations, atmospheric dynamics and the fire situation is analyzed. Along with the processes of the WV advection and evaporation we evaluate the contribution of pyrogenic emission of WV in spatial-temporal evolution of WV over ER during wildfires. The changes of water vapor at different heights in the troposphere and stratosphere are investigated. The results of a comparative analysis of WV contents during the periods of summertime atmospheric blockings in 1972 and 2010 are also presented. The near-infrared total-column precipitable water MODIS products (L3) are validated by upper-air radiosonde data.  相似文献   

17.
The EU Green Paper on Maritime Policy is the European response to the new generation of ocean strategies based on science, technology and innovation aimed at new objectives, such as the strengthening of security and access to new resources. The European character of the proposal is found in the presence of social, cultural and historical elements, what is called the “European vision”. The viability of a European vision of the oceans and the idea of maritime empire as an extension of the current concept of empire within the general context of emerging ocean strategies are the elements offered up for debate on this European Union initiative.  相似文献   

18.
The geomorphic, oceanographic, terrestrial and anthropogenic attributes of the European coastal zone are described and published data on ecosystem function (primary production and respiration) are reviewed. Four regions are considered: the Baltic Sea, Mediterranean Sea, Black Sea and the European Atlantic coast including the North Sea. The metabolic database (194 papers) suffers from a non-homogeneous geographical coverage with no usable data for the Black Sea which was therefore excluded from this part of our study. Pelagic gross primary production in European open shelves is, by far, the most documented parameter with an estimated mean of 41 mmol C m−2 d−1, the lowest value is reported in the Mediterranean Sea (21 mmol C m−2 d−1) and the highest one in the Atlantic/North Sea area (51 mmol C m−2 d−1). Microphytobenthic primary production, mostly measured in shallow areas, is extrapolated to the entire 0–200 m depth range. Its contribution to total primary production is low in all regions (mean: 1.5 mmol C m−2 d−1). Although macrophyte beds are very productive, a regional production estimate is not provided in this study because their geographical distribution along the European coastline remains unknown. Measurements of pelagic community respiration are clearly too sparse, especially below the euphotic zone, to yield an accurate picture of the fate of organic matter produced in the water column. With a mean value of 17 mmol C m−2 d−1, benthic community respiration consumes approximately 40% of the pelagic organic matter production. Estuaries generally exhibit high metabolic rates and a large range of variation in all parameters, except microphytobenthic primary production. Finally, the problem of eutrophication in Europe is discussed and the metabolic data obtained in the framework of the Land–Ocean Interactions in the Coastal Zone (LOICZ) project are compared with available direct measurements of net ecosystem production.  相似文献   

19.
The present extent of European ice coasts, their spatial changes in the past 50 years and the velocities of ice flow in marginal parts of tidewater glaciers were determined and mapped at a regional scale using space-borne image data, both optical and radar. The methods of satellite photogrammetry and radar interferometry provided efficient solutions to the integral estimation of ice-coast dynamics in the Franz Josef Land, Novaya Zemlya and Svalbard archipelagos. Studies revealed significant degradation of the ice coasts (–7.7% by length) compared to the situation represented in the available maps. The results obtained in the laboratory were verified during several field campaigns.  相似文献   

20.
Abstract. We describe a software system that allows even an inexperienced user to estimate the wave statistics at any location along the European coastal zone. The system is composed of a solid, well verified data set, a geographical tool, a modelling section and a statistical package. Their use is fully transparent to the user.  相似文献   

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