Artificial upwelling induced by ocean currents —Theory and experiment     

C.T. Hsieh  P.A. Huang  D.J. Li  L.L. Chu  C.L. Wu  N.T. Liang 《Ocean Engineering》1978,5(2):83-94

A submerged apparatus, which consists of a buoy, several horizontal contraction and expansion tubes (Venturi-type tubes) and a long pipe, is expected to be used to pump the subsurface sea-water (200–300 meter depth) containing abundant nutrients to surface layer (50–100 m) by the dynamic of ocean currents. i.e. an artificial upwelling without energy cost. A preliminary experiment and analysis are undertaken and shows that the capacity of pumping the nutrient-rich sea-water is worth to build a pilot prototype model.  相似文献   

The stability of fish stocks     

Gulland  J. A. 《ICES Journal of Marine Science》1977,37(3):199-204

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Estimation of winds over the sea from land-based measurements     

Jen-Men Lo  N. Al-Madani  M. A. Tayfun  D. Al-Ajmi 《Ocean Engineering》1994,21(7)

Simultaneous measurements of wind velocities at two different sites, one over the sea and the other over land, can differ substantially and therefore cannot be interchanged. In situations where the wind data at an offshore site are missing while simultaneous measurements from a land-based station exist, a linear mean-square estimation (LMSE) technique can be used to estimate the missing data. This technique relies on past wind data gathered simultaneously at the two locations, and it generates from the associated correlation a set of four transfer functions capable of predicting one data set from the other. In the present case, the LMSE technique is outlined briefly, and is then applied to construct seasonal transfer functions between a land-based station and two coastal/offshore sites in Kuwait. Comparisons between the actually observed wind characteristics and those predicted by the LMSE technique are favorable, and thus tend to confirm the applicability of the technique under appropriate conditions.  相似文献   

Offshore permafrost and gas hydrate stability zone on the shelf of East Siberian Seas   总被引：1，自引：0，他引：1  

N. N. Romanovskii  H. -W. Hubberten  A. V. Gavrilov  A. A. Eliseeva  G. S. Tipenko 《Geo-Marine Letters》2005,25(2-3):167-182

Dynamics of the submarine permafrost regime, including distribution, thickness, and temporal evolution, was modeled for the Laptev and East Siberian Sea shelf zones. This work included simulation of the permafrost-related gas hydrate stability zone (GHSZ). Simulations were compared with field observations. Model sensitivity runs were performed using different boundary conditions, including a variety of geological conditions as well as two distinct geothermal heat flows (45 and 70 mW/m²). The heat flows used are typical for the coastal lowlands of the Laptev Sea and East Siberian Sea. Use of two different geological deposits, that is, unconsolidated Cainozoic strata and solid bedrock, resulted in the significantly different magnitudes of permafrost thickness, a result of their different physical and thermal properties. Both parameters, the thickness of the submarine permafrost on the shelf and the related development of the GHSZ, were simulated for the last four glacial-eustatic cycles (400,000 years). The results show that the most recently formed permafrost is continuous to the 60-m isobath; at the greater depths of the outer part of the shelf it changes to discontinuous and patchy permafrost. However, model results suggest that the entire Arctic shelf is underlain by relic permafrost in a state stable enough for gas hydrates. Permafrost, as well as the GHSZ, is currently storing probable significant greenhouse gas sources, especially methane that has formed by the decomposition of gas hydrates at greater depth. During climate cooling and associated marine regression, permafrost aggradation takes place due to the low temperatures and the direct exposure of the shelf to the atmosphere. Permafrost degradation takes place during climate warming and marine transgression. However, the temperature of transgressing seawater in contact with the former terrestrial permafrost landscape remains below zero, ranging from –0.5 to –1.8°C, meaning permafrost degradation does not immediately occur. The submerged permafrost degrades slowly, undergoing a transformation in form from ice bonded terrestrial permafrost to ice bearing submarine permafrost that does not possess a temperature gradient. Finally the thickness of ice bearing permafrost decreases from its lower boundary due to the geothermal heat flow. The modeling indicated several other features. There exists a time lag between extreme states in climatic forcing and associated extreme states of permafrost thickness. For example, permafrost continued to degrade for up to 10,000 years following a temperature decline had begun after a climate optimum. Another result showed that the dynamic of permafrost thickness and the variation of the GHSZ are similar but not identical. For example, it can be shown that in recent time permafrost degradation has taken place at the outer part of the shelf whereas the GHSZ is stable or even thickening.  相似文献   

Effort distribution and catch patterns adjacent to temperate MPAs   总被引：7，自引：2，他引：7  

Murawski  Steven A.; Wigley  Susan E.; Fogarty  Michael J.; Rago  Paul J.; Mountain  David G. 《ICES Journal of Marine Science》2005,62(6):1150-1167

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Implementing a physical initialization procedure in a regional spectral model: impact on the short-range rainfall forecasting over South America   总被引：1，自引：0，他引：1  

A. M. B. NUNES  S. COCKE 《地球，A辑:动力气象学与海洋学》2004,56(2):125-140

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Erratum     

Otterlei  E.; Folkvord  A.; Nyhammer  G. 《ICES Journal of Marine Science》2002,59(4):850

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Sedimentology of a subtidal,tide-dominated sand body in the Yellow Sea,southwest Korea     

George DeVries Klein  Y.A. Park  J.H. Chang  C.S. Kim 《Marine Geology》1982,50(3):221-240

Odanam Satoe, a subtidal, tide-dominated sand body in the Yellow Sea, Korea, is linear in plan and asymmetrical in cross-section. It consists of fine- to medium-grained, well-sorted subangular sand. Bedforms consist of high-amplitude (1–2 m) sandwaves on the lower flanks of the gentler-sloping bar surface, and medium-amplitude (0.5-1 m) sandwaves on the sand body trough adjoining the steeper face, the bar crest and shallower parts of the gently sloping bar surface. Bedforms are absent on the relatively steeper bar surface, which is characterized by 2° slopes. Bedform orientation on the gentler slope is oblique by 30° to the bar crest, parallel to the sand-body crest on the crest itself, and opposite to the steeper sand-body face in the trough below the steeper slope of the bar.Bottom current velocity data show that tidal currents are semi-rotary with a flood time—velocity asymmetry over the gentler slope, and ebb time—velocity asymmetry over the steeper slope during most of the tidal cycle. Tidal-current flow parallels bar elongation over the steeper slope, whereas over the gentler slope, tidal-current flow is directed at 30° to the bar crest and changes to normal to the crest one hour prior to low tide. Bedform orientation mapped with side-scan sonar shows agreement with these flow directions.Sand dispersal around the sand body is controlled by time—velocity asymmetry and partial rotary flow directions of tidal currents. This circulation causes not only a trapezoidal mode of grain dispersal, but also westerly migration of the sand body documented from comparative bathymetric surveys in 1964 and 1980.  相似文献   

Immediate profile and planform evolution of a beach nourishment project with hurricane influences   总被引：1，自引：0，他引：1  

Nicole A. Elko  Ping Wang 《Coastal Engineering》2007

In this study, planform adjustment began during a period of calm weather immediately after nourishment and then the passage of one strong storm caused a substantial portion of the total profile equilibration. Weekly beach profiles, shoreline surveys, and nearshore wave measurements were conducted before, during, and immediately after construction of the 1100-m long Upham Beach nourishment project on the low-energy, west coast of Florida. This project was constructed in three segments: the wide north segment, the central segment, and the narrow south segment. With the exception of the relatively distant passage of Hurricane Charley, calm weather prevailed for 45 days following completion of the south and central segments. Construction of the wide north segment was completed on August 27, 2004. Substantial planform diffusion occurred prior to construction completion via formation of a 300-m long spit extending from the wide north segment. The shoreline orientation was changed abruptly due to this diffusion spit formation, as opposed to the gradual adjustment predicted by most long-term models. Planform adjustment was initiated prior to profile equilibration, and it did not require high-energy conditions. A simple vector sum model for determining the orientation of a potential diffusion spit was developed. This study recommends designing end transitions at the predicted diffusion spit orientation to avoid post-nourishment spit formation during future projects.  相似文献   

Importance of spawning location and timing to successful transport to nursery areas: a simulation study of Gulf of Alaska walleye pollock   总被引：2，自引：0，他引：2  

Hinckley  Sarah; Hermann  Albert J.; Mier  Kathy L.; Megrey  Bernard A. 《ICES Journal of Marine Science》2001,58(5):1042-1052

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