热带大西洋年际和年代际变率的时空结构模拟   总被引：10，自引：3，他引：10       下载免费PDF全文

赵珊珊  杨修群  朱益民 《海洋学报》2003,25(3):8-19

使用美国夏威夷大学发展的中等复杂程度海洋模式(IOM)在给定表面强迫条件下模拟了热带大西洋上层海洋年际和年代际变率的时空结构.利用NCEP的41a(1958～1998年)逐月平均表面资料作为强迫场,积分海洋模式41a作为控制试验,并利用模式分别做动量(风应力)通量和热量通量无异常变化的平行试验,与控制试验作比较.对3组试验模拟上层海洋变率状况的比较,并按年际和年代际时间尺度分别分析,揭示表面风应力和热通量异常对海表面温度和温跃层深度变化的影响,并比较了其影响的相对重要性.结果表明模式成功地模拟出了热带大西洋上层海洋的变率.模式模拟的海表面温度年际变化主要表现为弱ENSO型,年代际变化表现为南、北大西洋变化相反的偶极子型.在年际时间尺度上,热力强迫和动力强迫对海表温度变化都有贡献,其中赤道外海表面温度异常(SSTA)变化主要由热通量异常引起,而近赤道SSTA的变化主要由动量异常强迫引起.在年代际时间尺度上,热通量强迫的作用远比动量强迫重要.模式不仅能够模拟SST在年际和年代际时间尺度上的变率,还能够模拟温跃层深度在年际和年代际时间尺度上的变率.年际和年代际时间尺度上,温跃层深度的变率主要由动量异常决定,热通量异常强迫的贡献很小.  相似文献   

The Bering Sea—A dynamic food web perspective     

Kerim Aydin  Franz Mueter   《Deep Sea Research Part II: Topical Studies in Oceanography》2007,54(23-26):2501

The Bering Sea is a high-latitude, semi-enclosed sea that supports extensive fish, seabird, marine mammal, and invertebrate populations and some of the world's most productive fisheries. The region consists of several distinct biomes that have undergone wide-scale population variation, in part due to fisheries, but also in part due to the effects of interannual and decadal-scale climatic variation. While recent decades of ocean observation have highlighted possible links between climate and species fluctuations, mechanisms linking climate and population fluctuations are only beginning to be understood. Here, we examine the food webs of Bering Sea ecosystems with particular reference to some key shifts in widely distributed, abundant fish populations and their links with climate variation. Both climate variability and fisheries have substantially altered the Bering Sea ecosystem in the past, but their relative importance in shaping the current ecosystem state remains uncertain.  相似文献   

Genetic Diversity in Marine Molluscs: A Test of the Niche-Width Variation Hypothesis     

B. Lavm  E. Nevo 《Marine Ecology》1981,2(4):335-342

Abstract. A test of the niche width variation hypothesis was conducted in the three Mediterranean littoral species of the family Trochidae: Monodonta turbinata, M. turbiformis and Gibbula richardi. Allozymic variation encoded by 26 gene loci was analyzed, and the levels of polymorphism (P), heterozygosity (H) and allele diversity per locus (A) were estimated and appear to support the niche-width variation hypothesis. The broad-niche species, M. turbiformis and G. richardi are more polymorphic and heterozygous than the relatively narrow-niche M. turbinata (P = 0.571; 0.731 and 0.417; H = 0.108; 0.116 and 0.078; A = 2.025; 2.489 and 1.965, respectively).  相似文献   

Decadal Variability of Subsurface Temperature in the Central North Pacific     

Satoshi Sugimoto  Takashi Yoshida  Tadashi Ando 《Journal of Oceanography》2003,59(6):945-955

Decadal variability of subsurface temperature in the North Pacific has been investigated. Two dominant regions were found; the central subarctic region (CSa) and the north-eastern subtropical region (NESt). In CSa, cooling (warming) of wintertime subsurface temperature corresponds to the large (small) temperature gradient and southward (northward) shift of subsurface temperature front, associated with the increase (decrease) of positive wind stress curl and the southward (northward) shift of curl τ zero line with 2 years delay. It is suggested that the relocation of subtropical-subarctic boundary plays an important role. In NESt, importance of heat flux through the sea surface and heat divergence in the Ekman layer is also discussed. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

Is there a connection between high transport of water through the Rockall Trough and ecological changes in the North Sea?   总被引：1，自引：1，他引：1  

Holliday  N. Penny; Reid  Philip C. 《ICES Journal of Marine Science》2001,58(1):270-274

  相似文献   

Ten-year record of Thalassiosira nordenskioeldii population dynamics: comparison of aquaculture and non-aquaculture sites in the Quoddy Region     

Smith  Aaron C.; Martin  Jennifer L.; Ehrman  James M.; Kaczmarska  Irena 《ICES Journal of Marine Science》2001,58(2):391-397

  相似文献   

南海上层海洋热含量的年际和年代际变化   总被引：1，自引：0，他引：1  

何有海  关翠华 《热带海洋学报》1997,(1)

分析了1959—1988年南海表面至100m垂直平均温度（TAV）资料，结果表明：南海上层海洋热含量存在明显的准两年、4—5年和年代际振动。在E1Nino年，南海上层热含量显著增加。50年代末至70年代初，南海TAV为负距平，此后转为正距平。南海TAV的变化与ENSO事件、东亚冬季风和热带大气环流的变异密切相关。  相似文献   

Variation in Water Masses on Shelf of Northern Bering Sea in September 2016-2018     

Yingjie Wang  Na Liu  Lina Lin  Yan He  Bin Kong  Zhanhai Zhang 《Marine Geodesy》2020,43(3):285-301

Abstract

Based on hydrological data obtained during the 7th to 9th Chinese National Arctic Research Expeditions in the summers of 2016–2018, the main water structure on the shelf of the northern Bering Sea and the volume and heat fluxes of the Bering Strait throughflow were analyzed. Distinct variability was identified in the three Pacific water masses feeding the strait - Anadyr Water (AW), Bering Shelf Water (BSW) and Alaskan coastal water (ACW). Overall, the temperature and salinity of the entire section increased each year, with 2018 showing significant anomalies, i.e., a temperature anomaly of up to 1?°C and a maximum salinity anomaly of 2. From 2016 to 2018, the extent of the ACW gradually narrowed in the eastern part of this section, while the AW expanded eastward each year. The net volume transport through each of the three sections increased poleward from 1.65?Sv to 2.76?Sv, with the AW increasing from 0?Sv to 1.03?Sv, the BSW varying between 0.52–1.65?Sv, and the ACW gradually decreasing from 1.04?Sv to disappearing completely. The net heat fluxes were also poleward, varying between 25.77 TW and 61.50 TW, and showing a significant increase. Significant variations in magnitude and extent were observed in each water mass of the Bering Strait throughflow, which could produce widespread effects in the Arctic Ocean and the global ocean beyond.  相似文献   

Wind-driven interannual variability over the northeast Pacific Ocean     

Patrick F. Cummins  Gary S.E. Lagerloef 《Deep Sea Research Part I: Oceanographic Research Papers》2004,51(12):365

Interannual variability of the sea surface height (SSH) over the northeast Pacific Ocean is hindcast with a reduced-gravity, quasi-geostrophic model that includes linear damping. The model is forced with monthly Ekman pumping fields derived from the NCEP reanalysis wind stresses. The numerical solution is compared with SSH observations derived from satellite altimeter data and gridded at a lateral resolution of 1 degree. Provided that the reduced gravity parameter is chosen appropriately, the results demonstrate that the model has significant hindcast skill over interior regions of the basin, away from continental boundaries. A damping time scale of 2 to 3 years is close to optimal, although the hindcast skill is not strongly dependent on this parameter.A simplification of the quasi-geostrophic model is considered in which Rossby waves are eliminated, yielding a Markov model driven by local Ekman pumping. The results approximately reproduce the hindcast skill of the more complete quasi-geostrophic model and indicate that the interannual SSH variability is dominated by the local response to wind forcing. There is a close correspondence the two leading empirical orthogonal modes of the local model and those of the observed SSH anomalies. The latter account for over half of the variance of the interannual signal over the region.  相似文献   

Phytoplankton variability on the Faroe Shelf   总被引：2，自引：2，他引：2  

Gaard  Eilif; Hansen  Bogi; Heinesen  Signar P. 《ICES Journal of Marine Science》1998,55(4):688-696

  相似文献