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1.
Satellite altimeter needs to be calibrated to evaluate the accuracy of sea surface height data. The dedicated altimeter calibration field needs to establish a special calibration strategy and needs to evaluate its calibration ability. This paper describes absolute calibration of HY-2B altimeter SSH using the GPS calibration method at the newly Wanshan calibration site, located in the Wanshan Islands, China. There are two HY-2B altimeter passes across the Wanshan calibration site. Pass No. 362 is descending and the ground track passes the east of Dan’gan Island. Pass No. 375 is ascending and crosses the Zhiwan Island. The GPS data processing strategy of Wanshan calibration site was established and the accuracy of GPS calibration method of Wanshan calibration site was evaluated. Meanwhile, the processing strategies of the HY-2B altimeter for the Wanshan calibration site were established, and a dedicated geoid model data were used to benefit the calibration accuracy. The time-averaged HY-2B altimeter bias was approximately 2.12 cm with a standard deviation of 2.08 cm. The performance of the HY-2B correction microwave radiometer was also evaluated in terms of the wet troposphere path delay and showed a mean difference ?0.2 cm with a 1.4 cm standard deviation with respect to the in situ GPS radiosonde.  相似文献   

2.
Izvestiya, Atmospheric and Oceanic Physics - On July 5, 2016, NASA’s Juno station began flying around Jupiter in a meridional orbit, having detected eight cyclones near the poles in latitude...  相似文献   

3.
Nikiforov  S. L.  Ananiev  R. A.  Libina  N. V.  Dmitrevskiy  N. N.  Lobkovskii  L. I. 《Oceanology》2019,59(3):422-424
Oceanology - Abstract—The results of recent geological and geophysical expeditions indicate the activation of hazardous natural phenomena associated with ice gouging and representing a...  相似文献   

4.
Izvestiya, Atmospheric and Oceanic Physics - A coupled Earth’s thermosohere-ionosphere global dynamics model (for altitudes of 90–500 km) is presented. This model is based on a...  相似文献   

5.
The first map of the acoustic basement and the new map of chrons C1-C5E for the region of the East Scotia mid-ocean ridge have been made. The analysis of the maps and the calculations have indicated that the sea-floor spreading at the ridge’s flanks started in its southeast in the interval of chrons C5Er-6An (18.52–20.17 Ma BP). The maximal spreading rate (5.3 cm/year) was in the interval of chrons C5Bn-C5Br (14.78–15.97 Ma BP). Then, the spreading rate was slow and increased again from 3–6 Ma BP until the present. The spreading in the last 1–2 Ma was accompanied by the propagating of the axes southwards in the E1, E2, and E4 segments and northwards in the E8 and E9 segments.  相似文献   

6.
The peculiarities of the crustal structure within the Falkland Basin have been discussed. Maps of the free-air and Bouguer (2.3 g/cm3) gravity anomalies and their transforms have been made. The complex analysis of the anomalous gravity field has allowed us to confirm the continental origin of the crust. The zoning of the crust has been performed. The crust is thinned and is enriched in basic and ultrabasic intrusions. A map demonstrating the distribution of the faults within the studied water area has been made. A conclusion has been reached about the leading role played by tension processes throughout the evolution of the crust within the studied water area.  相似文献   

7.
《Oceanologica Acta》2002,25(5):267-269
This article outlines the background and planning for a South American workshop on marine biodiversity in Concepción, Chile, 28–30 October, 2002. This first CoML/POGO effort in the Southern hemisphere, pursuant to the Sao Paulo declaration began with presentations in all major coastal states and brings together key South American researchers to take advantage of new research concepts emerging from the Census projects.  相似文献   

8.
Pituitary gland, or pituitary for short, is characteristic of all vertebrates. As a “master gland” controlling a multitude of important functions in the body, its evolutionary origin has been an object of investigations of evolutionary biology for two centuries. Previous morphological, ultrastructural and immunohistochemical studies suggested the homology of the Hatschek’s pit of amphioxus and vertebrate pituitary. Developmental genetics study showed that the development of Hatschek’s pit and vertebrate pituitary is both subject to regulation by the common genes such as Pit1, Lhx3 and BMP3b. Our recent studies demonstrated that the Hatschek’s pit is able to secrete growth hormone (GH)-like hormone and thyroid-stimulating hormone (TSH)-like hormone that both play functions similar to vertebrate GH and TSH. We thus think that the emergence of Hatschek’s pit represents one of important events during endocrine network evolution, which laid a foundation for the subsequent formation of a hypothalamic-pituitary system in vertebrates.  相似文献   

9.
Izvestiya, Atmospheric and Oceanic Physics - The model balance equation of turbulence is represented in the form of the first law of thermodynamics. The forms for entropy are derived with an...  相似文献   

10.
The primary goal of Australia’s National Representative System of Marine Protected Areas (NRSMPA) is to establish a comprehensive, adequate and representative system of MPAs. This study identifies a glaring contradiction to this policy. The provinces of Christmas and Cocos Islands are among the most unique and threatened marine bioregions in Australia, yet receive no protection from the NRSMPA. The lack of protection appears to be due to difficulties with multiple governance arrangements and other political priorities. These issues have already caused biodiversity loss in the terrestrial environment of these bioregions. The Australian Government must include the Christmas and Cocos provinces in the NRSMPA otherwise it risks irreversible loss of marine biodiversity in these unique bioregions.  相似文献   

11.
First,Wirsching's model,which is widely employed in fatigue reliability anlysis of marine andoffshore structures,is analysed systematically.It is found that the very important random variable △ inWirsching's model can not be directly determined from fatigue experiment because of the irreversibility offatigue test,and in fact,what Wirsching studied from testing results is not △ but α of the statistical Miner'srule.Second,by use of the statistical Miner's rule,a modified Wirsching's model is proposed.Thirdly andmore importantly,based on the two-dimensional probabilistic Miner's rule,a new model is established forfatigue reliability analysis of structural components subjected to specified cyclic loading of variableamplitude or stochastic time history.In the end,an example is presented,from which it will be seen thatthis new model is very convenient to use and feasible to engineering practice.  相似文献   

12.
The data of beam propagation of internal waves into the ocean are confirmed by several analytical solutions of the linear long wave theory. The obtained solutions are applied to calculate the mode of the internal waves.  相似文献   

13.
The global VDM database, which was later supplemented by new determinations published in the world literature (a total of 3194 determinations), is used as the basis for addressing the VDM behavior in the Phanerozoic (0–542 Ma) and up to 580 Ma. The results revealed a positive linear trend to higher VDM values from 3.5 × l022 Am2 to 5.7 × l022 Am2. Against this background, fluctuations of the mean VDMs occur with a periodicity of about 40 Myr. In the Phanerozoic, prominent minima of the intensity are found in the time intervals of 510–520, 420–460, 340–370, 290–300, 240–270, 190–210, 165–140 Ma (chrons M17–M43), 130–120 Ma (chrons M2–M10), 100–110 Ma (chron C34), 75–85 Ma (chrons C33 and the beginning of chron C34), 70–60 Ma (chrons C31–C27), and 40–15 Ma (chrons C18–C5AD). The distribution of the VDMs appears to reflect the paleomagnetic field behavior and may be taken into account in a magnetization model for the reversely magnetized oceanic crust.  相似文献   

14.
Experimental Investigation of the Decay from A Ship’s Propeller   总被引:1,自引:0,他引:1  
In the present study,an experimental investigation of the decay of the maximum velocity and its turbulent characteristics behind a ship propeller,in "bollard pull" condition(zero speed of advance),is reported.Velocity measurements were performed in laboratory by use of a Laser Doppler Anemometry(LDA) measurement system.Earlier researchers described that the maximum axial velocity is constant at the initial stage of a ship’s propeller jet(Fuehrer and Rmisch,1977;Blaauw and van de Kaa,1978;Berger et al.,1981;Verhey,1983) as reported in a pure water jet(Albertson et al.,1950;Lee et al.,2002;Dai,2005),but a number of researchers disagreed with the constant velocity assumption.The present study found that the maximum axial velocity decays in the zone of flow establishment and the zone of established flow with different rates.The investigation provides an insight into the decays of both the maximum velocity and the maximum turbulent fluctuation in axial,tangential and radial components and the decay of the maximum turbulent kinetic energy.Empirical equations are proposed to allow coastal engineers to estimate the jet characteristics from a ship’s propeller.  相似文献   

15.
Multi-species fisheries are complex to manage and the ability to develop an appropriate governance structure is often seriously impeded because trading between sustainability objectives at the species level, economic objectives at the fleet level, and social objectives at the community scale, is complex. Many of these fisheries also tend to have a mix of information, with stock assessments available for some species and almost no information on other species. The fleets themselves comprise fishers from small family enterprises to large vertically integrated businesses. The Queensland trawl fishery in Australia is used as a case study for this kind of fishery. It has the added complexity that a large part of the fishery is within a World Heritage Area, the Great Barrier Reef Marine Park, which is managed by an agency of the Australian Commonwealth Government whereas the fishery itself is managed by the Queensland State Government. A stakeholder elicitation process was used to develop social, governance, economic and ecological objectives, and then weight the relative importance of these. An expert group was used to develop different governance strawmen (or management strategies) and these were assessed by a group of industry stakeholders and experts using multi-criteria decision analysis techniques against the different objectives. One strawman clearly provided the best overall set of outcomes given the multiple objectives, but was not optimal in terms of every objective, demonstrating that even the “best” strawman may be less than perfect.  相似文献   

16.
New data on the Onega River estuary’s hydrological and morpholithodynamic regimes are presented. The river’s bottom structure and soil lithology are described on the basis of field sonar survey materials. Proceeding from the analysis of the hydrographic maps, the dynamics of the Onega River’s mouth bar is tracked over the period of 1830–2000.  相似文献   

17.
Izvestiya, Atmospheric and Oceanic Physics - In the great variety of vortex motions in the atmosphere, concentrated vortices, attracting increased interest from the point of view of both...  相似文献   

18.
Sea area is an important area of oil and gas exploration in China. It has been found that China’s sea area mainly consists of coal type oil and gas, and the exploration of coal-bearing series source rocks has become an important part of oil and gas exploration there. Through years of comprehensive geological research in China’s sea area, it has been revealed that it has undergone multiple occurrences of tectonic opening and closing movements in varying degrees in the Paleogene, forming 26 Cenozoic sedimentary basins of various types, such as active continental margin, passive continental margin, transitional continental margin and drift rift basins. In the present study, it is observed for the first time that coal type source rocks are mainly developed in 14 continental margin basins in China’s sea area, revealing that a very large C-shaped coal-bearing basin group developed there in the Cenozoic. Next, based on the coupling analysis of paleoclimate, paleobotany, paleogeography and paleostructure, it is observed that there are five coal-forming periods in China’s sea area, namely the Paleocene, Eocene, early Oligocene, late Oligocene and Miocene-Pliocene, and the coal-forming age is gradually new from north to south. It is also found that the coal seams in the sea area are mainly developed in three coal-forming environments in Cenozoic, namely delta, fan delta and tidal flat-lagoon. The coal seams developed in different environments are characterized by thin thickness, many layers and poor stability. However, the coal-bearing series source rocks in China’s sea area have a wide distribution range, very high thickness and large amount, thus forming a material basis for the formation of rich coal type oil and gas.  相似文献   

19.
《Marine Policy》1999,23(2):177-190
This paper has two aims. First, New Zealand’s quota management system is analysed using a simple analytical economic model. Second, the paper describes how the system has evolved in response to pressures since implementation. The quota management system has provided a remarkably robust platform for addressing fisheries management problems during its first ten years of operation. It also provided the government with an instrument for settling Maori fishing claims. In 1996, the unsubsidised New Zealand fishing industry exported most of its harvest to highly competitive international markets. The paper concludes with a discussion of contemporary challenges.  相似文献   

20.
Schreider  A. A.  Sazhneva  A. E.  Varga  P.  Denis  C. 《Oceanology》2019,59(5):771-776
Oceanology - Data of the International Bank of Digital Information on the time distribution of the virtual dipole moment (VDM), supplemented by data of more recent studies (a total of 5645 values),...  相似文献   

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