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1.
To meet the increasing demand of national spatial database infrastructure construction and application, a concept model of China‘ s coastal zone scientific data platform is established based on the information feature analysis of a compound dataset, consisting of remote sensing data and conventional data. Based on this concept model, the detailed logical database structure and the storage strategy of remote sensing data and their metadata using ArcSDE are designed. The complicated technology of multisources data combination in this research is crucial to the future coastal zone and offshore database construction and practical running, which will provide intelligent information analysis and technological service for coastal zone and offshore investigation, research, development and management.  相似文献   

2.
《海洋学报(英文版)》1996,15(4):539-556
AstudyofanchoringgeographiccoordinatesandcalculatingzenithandazimuthofsunandscannerforoceanicsatellitedataINTRODUCTIONThescan...  相似文献   

3.
1IntroductionThe21stcenturyisacenturyoftheocean,andallofusmustprepareforthecomingofthiscentury.Asoceanologicalresearchers,wehavemanythingstodotopromotethecon-structionandapplicationofdigitaloceaninna-tionalspatialdatainfrastructure,suchascoastalintegrateddatamanagement,intelli-gentinformationanalysisandsubjectinforma-tionextractionofoceanologicremotesensingdata,nationalandprovincialremotesensingin-formationservicesystemsofoceanology,e-cologicalandenvironmentalinformationser-vicesystemandsharin…  相似文献   

4.
Two multispectral threshold techniques have been developed and tested for the automatic classification of AVHRR/NOAA and SEVIRI/Meteosat-10 data. They provide day-and-night detection and the assessment of cloud-cover parameters, as well as the discrimination of precipitation zones and severe weather phenomena. The validation of output information products, which has been performed with ground-based conventional meteorological observations and radar data, as well as with independent satellite-based estimates of cloud cover and precipitation parameters, confirms the feasibility of developed techniques and reasonable accuracy of output products. Therefore, the technique is concurrent to those implemented in current foreign satellite centers.  相似文献   

5.
In many scientific fields such as meteorology, biology, geography, oceanography and astronomy, the angle value is very important, for example, wind directions, and the directions on which animals and birds migrate. This kind of data is called as directional data. In some problems, it is not expressed as "angle" value, such as month by month mean temperature, however, it can be changed into a directional data through some transformations. The statistical method of directional data means that the methods of mathematical statistics are used in the treatment of directional data. In this way, data are considered as the points on two-dimensional cycle or higher dimensional sphere. Therefore, this method can also be called statistics on sphere. Because of its own characteristical feature, the statistics of directional data much differ from common statistics. Up to now, research work in this field has just started in China. In this paper, a statistical study on typhoon moving directions after their formation ov  相似文献   

6.
[1]Battisti D S. 1988. The dynamics and  相似文献   

7.
The variability in global oceanic evaporation data sets was examined for the period 1988-2000. These data sets are satellite estimates based on bulk aerodynamic formulations and include the NASA/Goddard Space Flight Center Satellite-based Surface Turbulent Flux version 2 ( GSSTF2), the Japanese-ocean flux using remote sensing observations (J-OFURO), and the Hamburg Ocean-Atmosphere Parameters and Fluxes from Satellite version 2 (HOAPS2). The National Center for Environmental Prediction (NCEP) reanalysis is also included for comparison. An increase in global average surface latent heat flux (SLHF) can be observed in all the data sets. Empirical mode decomposition (EMD) shows long-term increases that started around 1990 for all remote sensing data sets. The effect of Mt. Pinatubo eruption in 1991 is clearly evident in HOAPS2 but is independent of the longterm increase. Linear regression analyses show increases of 9.4%, 13.0%, 7. 3%, and 3.9% for GSSTF2, J-OFURO, HOAPS2 and NCEP, for the periods of the data sets. Empirical orthogonal function (EOF) analyses show that the pattern of the first EOF of all data sets is consistent with a decadal variation associated with the enhancement of the tropical Hadley circulation, which is supported by other satellite observations. The second EOF of all four data sets is an ENSO mode, and the correlations between their time series and an SO1 are 0.74, 0.71,0.59, and 0.61 for GSSTF2, J-OFURO, HOAPS2, and NCEP in that order. When the Hadley modes are removed from the remote sensing data, the residue global increases are reduced to 2.2% , 7. 3%, and 〈 1% for GSSTF2, J-OFURO and HOAPS, respectively. If the ENSO mode is used as a calibration standard for the data sets, the Hadley mode is at least comparable to, if not larger than, the ENSO mode during our study period.  相似文献   

8.
1 IntroductionIt is well known that interaction between the trop-ical ocean and atmosphere produces the largest inter-annual climate signal, El Nino-Southern Oscillation(ENSO). In past decades many efforts have been madein understanding and predicting ENSO: such as the hy-pothesis of Bjerknes (1969) that ENSO arises as aself-sustained cycle in which SSTA in the Pacific O-cean causes the trade winds to strengthen or slackenand that this in turn drives the ocean circulation changesthat …  相似文献   

9.
An automatic measuring system called “FerryBox” was installed in the North Sea on a ferry travelling between Germany (Cuxhaven) and Great Britain (Harwich), enabling online oceanographic and biological measurements such as salinity, temperature, fluorescence, turbidity, oxygen, pH, and nutrient concentrations. Observations made along the ferry transect reveal characteristic phenomena such as high salinity inflow through the Channel into the Southern Bight, algal bloom dynamics and related oxygen and pH changes. Combination of these online observations with remote sensing enhances the spatial resolution of the transect related measurements. Several examples of the synergy between these two measuring strategies are shown, both for large-scale algal blooms in the North Sea as well as for local intense but short-term blooms in the German Bight. Coherence of the data sets can be gained and improved by using water transport models in order to obtain synoptic overviews of the remotely sensed and FerryBox related parameters. Limitations of the currently used algorithms for deriving chlorophyll-a from remote sensing images for coastal and shelf seas (Case-2 water) are discussed, as well as depth related processes which cannot be properly resolved on the basis of water intake at a fixed point. However, in unstratified coastal waters under normal conditions FerryBox data represent average conditions. The importance of future applications of this combination of methods for monitoring of coastal waters is emphasized.  相似文献   

10.
The Ghana margin displays one of the best-known transform margins. Studies of the margin have provided the framework for a number of conceptual models aimed at understanding transform margin development worldwide. However, the deep structure of the margin is poorly known as knowledge is based only on wide-angle refraction measurements obtained from two separate localities on the margin. Consequently, complexities in the rift–shear margin architecture have been overlooked by current interpretations of margin development. Based on combined analysis of a detailed grid of ∼2710 km multichannel (MCS) lines and potential field data, we provide new insights into the structural architecture and tectonic development of the Ghana margin. In particular, we outline the deep structure of the entire margin using a series of 2D gravity modelled transects constrained by MCS and published wide-angle data. Our study reveals more complex rift–shear margin architecture than previously envisaged. We demonstrate that the main transform boundary representing the continental extension of the Romanche Fracture Zone, is actually composed of two distinct margin segments, i.e., the ENE–WSW trending sheared margin segment of the Cote d’Ivoire-Ghana Ridge and the NE–SW trending rift-influenced sheared margin segment of the Ghana Platform. These segments evolved under varying stress regimes, and during different time intervals. West of the transform margin, divergent rifting during the Early Cretaceous initiated the development of the Deep Ivorian Basin, essentially, as a single major pull-apart structure. However, east of the shear zone, oblique rifting resulted in the development of the Eastern Ghana Slope Basin as a composite of at least two coalescing pull-apart basins displaced along strike-slip faults. Our structural interpretation of the transform boundary geometry shows that the ridge and platform margin segments were each subjected to separate thermal influences from two different migrating spreading centres. Tectonic uplift of the ridge began through transpression during mid-Albian time following a change in relative direction of plate motion from NE–SW to ENE–WSW. However, the ridge uplift was amplified by thermal heating from a previously undocumented spreading centre whose progressive westward migration along the ridge followed closely after the Albian transpressional phase. The structural architecture of the Ghana margin resulted from a combination of factors, notably, pre-existing basement structure, plate boundary geometry, the relative direction of plate motion and thermal heating.  相似文献   

11.
In this study, the outgoing longwave radiation (OLR) data of eight years have been used to investigate the annual and interannual variations of large-scale circulation over the tropics. The results of EOF analysis indicate that the first three eigenvectors reflect the essential features in OLR annual variation. However, they contribute little to the interannual change. In comparison, the fourth to the sixth components have very large year-to-year variations. The pronounced anomalies are located over the tropics with east-west dipole pattern. It implies that ENSO events are related closely to the variation of the Walker circulation.  相似文献   

12.
13.
We pioneered a retrospective analysis of Black Sea hydrophysical fields for the period from 1971 to 1993. We describe a reanalysis algorithm based on the assimilation (in a σ-coordinate circulation model) of observed temperature and salinity data obtained on hydrophysical test areas. The thickness of the cold intermediate layer (CIL) and its freezing capacity for 1985 to 1993 were found to be increasing. At the levels of 0, 50, 75, and 100 m, the tendency of variations in annual values of level-averaged temperature is negative. At the level of 200 m and deeper, the linear trends of the interannual course of temperature are positive. We found that the linear trends of interannual variations in salinity are negative in the upper layer of 0 to 50 m and positive at 75 m and deeper. The sea-water circulation in the layer from 0 to 300 m was observed to be maximum in February–March and minimum in September–October. The characteristic of the linear trend of interannual variations in the kinetic energy of currents averaged over the sea surface is negative, while its value is positive in the layer from 50 to 100 m. Some factors responsible for the formation of hydrophysical fields in the sea and their seasonal and interannual variations were indicated. We revealed that there is a qualitative resemblance between seasonal and interannual variations [4, 26] in temperature, salinity, and kinetic energy.  相似文献   

14.
On the basis of the time series of AVHRR data from NOAA satellites and the geographical information system PURSIS, fluctuations of the plume front and the turbidity maximum in the Hangzhou Bay, reflected by the distributions of temperature and suspended sediment concentration respectively, are studied in view of long-term behaviors or seasonal and tidal cycles. The data suggest that the effect of front plays an important role in the development of the turbidity maximum close to the Changjiang Estuary > while the effect of tide dominates over the development of another very turbid water situated in the shoal areas in the southern Hangzhou Bay.  相似文献   

15.
Rongxing Li 《Marine Geodesy》2013,36(2-3):115-127
Shape from shading is one of the methods that derive geometric information of objects from analysis of monocular images. Application of this technique to underwater sonar images enables the conversion of imposed reflectance characteristics in sonar images to shape information, namely, slopes, about the seafloor surface. A combination of this shape information and available sparse distributed depth points results in improved dense bathymetric data.

The reconstruction of shape models of seafloor surfaces from sonar images is treated as an inverse problem and is solved by the regularization theory. Sparse gridded points are used for boundary constraints. The regularization is implemented as a relaxation procedure with a hierarchical structure of multiresolution grids.  相似文献   

16.
Physiology corrupts geochemical records of mollusk shells in many ways, e.g., by actively controlling the incorporation of trace elements in the skeleton. However, the effects of variable biomineralization rates and growth cessation have largely remained unconsidered. Mediated by endogenous timekeeping mechanisms, mollusks stop growing skeletal material on a regular basis ranging from ultradian to annual timescales. During growth cessation, the shells do not record environmental conditions. Shell growth also stops when environmental conditions are beyond the physiological tolerance of the organism, e.g., above and below genetically determined, species-specific thermal extremes where shell growth slows and eventually ceases. Such growth disruptions can occur at non-periodic time intervals. Due to growth retardations and halts, proxy records of mollusk shells are thus incomplete, and reconstructed environmental amplitudes prone to truncation. Furthermore, environmental records are biased toward the physiological optimum of the animal. Favorable environmental conditions increase shell growth, whereas adverse environmental conditions result in reduced shell production and lowered overall metabolism. Not least, the duration of the growing season and overall growth rate decrease as the mollusk grows older. Mathematical modeling approaches can significantly improve proxy records obtained from mollusk shells. For example, if the duration of growth cessation is known, it may be possible to model the missing environmental record. It is also fairly easy to account for age-related growth trends, or variable time-averaging in different portions of the shell. However, a major premise for a reliable interpretation of proxy records from a mollusk shell or other organisms secreting biogenic hard parts is a proper understanding of the physiology, and of course, a high-resolution record of the many different environmental factors that may influence physiology and shell growth. The present paper reviews examples from the literature, and unpublished data on how physiology influences geochemical proxy records from mollusk shells, and presents methods how to eliminate such adverse effects.  相似文献   

17.
There is a pressing need for standardization of data derived from bathy‐metric swath‐mapping systems. Currently several dozen multibeam and sidescan sonar data formats exist within the oceanographic community, and more can be expected as new systems are developed. Without some standardization of swath‐mapping data formats, the capability for use and integration of data from different systems will be severely compromised.

This paper presents a strategy for organizing swath bathymetry data in a logical modular fashion that will allow data from all current swath bathymetric sonar systems to be stored and accessed in a common fashion. We have chosen the approach of defining compact efficient modules for each logically independent portion of a data record and storing it in a manner that is portable between diverse computer architectures and operating systems. This approach is extensible to accommodate new types of data. Although specifically developed for swath bathymetry, this format is also capable of supporting digital sidescan data and other types of swath data.  相似文献   

18.
The article presents the results of shipboard and satellite measurements in the surface layer of the Baltic, Norwegian, and Barents seas during legs from the Baltic to the White Sea in June–August 2014–2016. Special attention is paid to marine phytoplankton blooms of cyanobacteria in the Baltic Sea and coccolithophores in the Barents Sea. No blooms were found in the Norwegian Sea. The efficiency of combined application of in situ and satellite optical methods for studying the parameters of phytoplankton blooms is shown.  相似文献   

19.
In this study demersal survey data for the period 1990–1999 are used to investigate the average distribution of the Cape hake Merluccius capensis and M. paradoxus off Namibia in terms of density and mean length. Further, biomass estimates are compared on the basis of depth and density stratification. The main distribution of M. capensis was north of 27°S and that of M. paradoxus south of 24°S. M. paradoxus was deeper than M. capensis. For both species, average length increased with depth. M. paradoxus expanded its range to the north through the 1990s as its population size (off South Africa and Namibia) increased. In Namibian waters, small M. paradoxus were found only south of 25°S. Mean length of M. capensis increased north of 21°S, largely as a result of decreased numbers of small fish in shallower water. Abundance estimates stratified by depth were no different from those post-stratified on similar densities.  相似文献   

20.
Offshore waters provide resources for human beings,while on the other hand,threaten them because of marine disasters.Ocean stations are part of offshore observation networks,and the quality of their data is of great significance for exploiting and protecting the ocean.We used hourly mean wave height,temperature,and pressure real-time observation data taken in the Xiaomaidao station(in Qingdao,China)from June 1,2017,to May 31,2018,to explore the data quality using eight quality control methods,and to discriminate the most effective method for Xiaomaidao station.After using the eight quality control methods,the percentages of the mean wave height,temperature,and pressure data that passed the tests were 89.6%,88.3%,and 98.6%,respectively.With the marine disaster(wave alarm report)data,the values failed in the test mainly due to the influence of aging observation equipment and missing data transmissions.The mean wave height is often affected by dynamic marine disasters,so the continuity test method is not effective.The correlation test with other related parameters would be more useful for the mean wave height.  相似文献   

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