检索结果-南通市图书馆

Relative importance of wind and buoyancy forcing for interdecadal regime shifts in the Pacific ocean

在线全文

学校读者我要写书评

暂无评论

Science China Earth Sciences 2003年第5期46卷 417-427页

作者：王东晓王佳吴立新刘征宇 LaboratoryofTropicalMarineEnvironmentalDynamics SouthChinaSeaInstituteofOceanologyChineseAcad-emyofSciences InternationalArcticResearchCenter UniversityofAlaska DepartmentofAtmosphericandoceanicSciences UniversityofWisconsin-Madison

Miami Isopycnal Coordinate ocean Model (MICOM) is applied here to simulate the interdecadal climatic change in the Pacific ocean. The surface forcing functions from January 1945 through to December 1993 are derived from the Comprehensive ocean and Atmospheric Data Set (COADS). Such a numerical experiment reproduces the observed basin-wide evolution for the interdecadal variability of the heat content in the upper 400 m layers. The teleconnections between the central North Pacific, the Gulf of Alaska, and the eastern and western tropical Pacific oceans are captured very well. Two additional experiments are performed to investigate the rela-tive importance of anomalous wind and buoyancy forcing regarding the regime shift. The results show that the anomalous buoyancy forcing is the dominant factor in the North Pacific and the sub-tropics, whereas the anomalous wind forcing is more important in the tropical Pacific than the other factors. Subduction is intrinsic physics for the interdecadal variability in the midlatitudes and the northern subtropics, whereas other mechanisms are involved in the tropical Pacific.

关键词： Pacific ocean, regime shift, relative importance, buoyancy forcing.

Observational estimation of heat budgets on drifting ice and open water over the Arctic ocean

在线全文

学校读者我要写书评

暂无评论

Science China Earth Sciences 2003年第6期46卷 580-591页

作者：卞林根高志球陆龙骅张雅宾 C.Roger X.D.Zhang ChineseAcademyofMeteorologicalSciences IARC/Frontier Fairbanks IARC/Frontier Fairbanks

Estimates of the surface heat budget over drifting ice and open water in the Arctic ocean are made using eddy correlation and flux-profile methods using data obtained from drifting ice and from the R/V Xuelong in the Chinese National Arctic Research Expedition during August 19—24,1999. The results show that the net radiation received by the ice surface is mainly lost through the sensible heat flux and the heat flux due to melting ice, and the latent heat flux making small contribution to the heat balance. However, the heat balance of the open water surface was dominated by the radiative flux whereas the latent and sensible heat fluxes and the oceanic heat flux were greater than those on the sea-ice surface. These results emphasize that thermodynamic processes are quite different between air/open water and air/sea-ice over the Arctic ocean which is important when considering the effect of sea-air-ice interaction on climate change process dur-ing the summer period.

关键词： Arctic ocean, drifting ice, open water, turbulence flux, heat balance.

Distribution of ^(226)Ra in the Arctic ocean and the Bering Sea and its hydrologic implications

在线全文

学校读者我要写书评

暂无评论

Science China Earth Sciences 2003年第5期46卷 516-528页

作者：邢娜陈敏黄奕普蔡平河邱雨生 Departmentofoceanography XiamenUniversity

Radium-226 (226Ra) activities were measured in the surface water samples collected from the Arctic ocean and the Bering Sea during the First Chinese National Arctic Research Ex-pedition. The results showed that 226Ra concentrations in the surface water ranged from 0.28 to 1.56 Bq/m3 with an average of 0.76 Bq/m3 in the Arctic ocean, and from 0.25 to 1.26 Bq/m3 with an average of 0.71 Bq/m3 in the Bering Sea. The values were obviously lower than those from open oceans in middle and low latitudes, indicating that the study area may be partly influenced by sea ice meltwater. In the Bering Sea, 226Ra in the surface water decreased northward, probably as a result of the exchange between the 226Ra-deficient sea ice meltwater and the 226Ra-rich Pacific water. In the Arctic ocean, 226Ra in the surface water increased northward and eastward. This spa-tial distribution of 226Ra reflected the variation of the 226Ra-enriched river component in the water mass of the Arctic ocean. The vertical profiles of 226Ra in the Canadian Basin showed a concen-tration maximum at 200 m, which could be attributed to the inputs of the Pacific water or/and the bottom shelf water with high 226Ra concentration. This conclusion was consistent with the results from 2H, 18O tracers.

关键词： Arctic ocean, Bering Sea, 226Ra, distribution.

Investigations on distributions and fluxes of sea-air CO_2 of the expedition areas in the Arctic ocean

在线全文

学校读者我要写书评

暂无评论

Science China Earth Sciences 2003年第6期46卷 569-579页

作者：王伟强陈立奇杨绪林黄宣宝 ThirdInstituteofoceanography StateOceanicAdministration KeyLaboratoryofGlobalChangeandMarine-AtmosphericChemistry StateOceanicAdministrationXiamen361005China ChineseArcticandAntarcticAdministration

The distributions and fluxes of sea-air carbon dioxide were investigated the first time based on the firsthand data collected during the First Chinese National Arctic Research Expedition. The results revealed that values of atmospheric CO2 partial pressure (Pa) measured in the sum-mer during the expedition fell between 352 and 370 (x10?6 CO2·Air?1, same unit below) with an average value of 358. Particularly, Pa appeared high in the northern sea areas of Poitlay. However, the values of CO2 partial pressure at the surface layer of seawater (Pw) ranged from 98 to 580 with the difference between the low and high being 472. The average value ofPw was 242, which is 116 lower than that of the correspondingP a. In addition, the distribution ofPw was roughly low in the west and north, but high in the east and south. These phenomena were closely related to plankton, ice, water temperature and circulation of the region. The estimation in carbon fluxes showed that the patterns in distribution were similar through different calculating methods with an exception in eastern sea areas of the region where a weak source of atmospheric CO2 was indi-cated. Most sea areas of the region were sinks or strong sinks of atmospheric CO2. However, the magnitudes in the fluxes were different. The average values varied from 6.57 (Liss method) to 26.32 ***2·m?2·h?1 (14C method) with a difference of about 4 times between the low and high, which is 2 to 10 times as high as the global average. Compared with the fluxes in the same region obtained using model of Takahashi, Feely et al., the values determined based on Wanninkhof coef-ficient calculation were 2.38 times as great as those obtained by them.

关键词： carbon flux, distribution, the Arctic ocean, carbon dioxide.

Effects of Second Order Scattered Wave in Stratified ocean

在线全文

学校读者我要写书评

暂无评论

Marine Science Bulletin 2001年第1期3卷 9-18页

作者：黄华詹杰民朱顶金廖德驹 Dept. of Applied Mechanics and Eng. Zhongshan University Guangzhou 510275 Dept. of Applied Mechanics and Eng. Zhongshan University Guangzhou 510275y using the theories on Stokes multicolored water waves and taking the two- layer ocean as a basic model of stratified ocean the paper analyzes the problems related to the effects of the nonlinear water wave on offshore structures. A mathematical expression is presented to describe second order wave radiation conditions. Using integral principle the analytical integral solutions are given to evaluate second order scattered wave loads on general vertical circular cylinders in the two-layer ocean and the special recurrence formulas for infinite integrals over free and stratified surfaces are derived.

By using the theories on Stokes multicolored water waves and taking the two- layer ocean as a basic model of stratified ocean, the paper analyzes the problems related to the effects of the nonlinear water wave on offshore structures. A mathematical expression is presented to describe second order wave radiation conditions. Using integral principle, the analytical integral solutions are given to evaluate second order scattered wave loads on general vertical circular cylinders in the two-layer ocean, and the special recurrence formulas for infinite integrals over free and stratified surfaces are derived.

关键词： Stratified ocean, second order wave, two layer ocean, scattering, diffracting, wave load

Chemical Fluxes of Asian Rivers into oceans and their Controlling Factors

在线全文

学校读者我要写书评

暂无评论

Marine Science Bulletin 2001年第2期3卷 30-37页

作者：杨守业李从先刘曙光 Laboraatory of Marine Geology University Shanghai 200092 Laboraatory of Marine Geology University Shanghai 200092~~

Chemical fluxes of Asian rivers into oceans bear different regional variations. Three zones are characteristic of distinct dissolved sediment loads and yields and ionic *** into oceans in China play an important role in Asia because of their different chemical fluxes, among which those draining the Loess Plateau have high ionic concentration, low water discharges and dissolved sediment loads and ***, vegetation, soil and strata lithology, chemical weathering intensity and tectonic activity dominate chemical fluxes of Asian rivers into oceans, and different factors have different effects on the chemical fluxes of separate regional rivers. Rising of the Tibet Plateau also exerts an important influence on chemical compositions of rivers originating from it.

关键词： Chemical flux, Asian rivers into ocean, controlling factors

Zircon SHRIMP U-Pb ages and trace element geochemistry of the Kuhai gabbro and the Dur'ngoi diorite in the southern east Kunlun tectonic belt, Qinghai, Western China and their geological implications

在线全文

学校读者我要写书评

暂无评论

Science China Earth Sciences 2007年第z2期50卷 331-338页

作者： LI WangYe LI ShuGuang GUO AnLin SUN YanGui ZHANG GuoWei CAS Key Laboratory of Crust-Mantle Materials and Environments School of Earth and Space Sciences University of Science and Technology of China Hefei 230026 China CAS Key Laboratory of Crust-Mantle Materials and Environments School of Earth and Space Sciences University of Science and Technology of China Hefei 230026 China Department of Geology Northwest University Xi'an 710069 China Remote Sensing Center of Qinghai Institute of Geological Survey Xining 810012 China Department of Geology Northwest University Xi'an 710069 China

Timing of the intermediate-basic igneous rocks developed in the area of Kuhai-A'nyêmaqên along the southern east Kunlun tectonic belt is a controversial issue. This paper presents new zircon SHRIMP U-Pb dating data for igneous zircons from the Kuhai gabbro and the Dur'ngoi diorite in the Kuhai-A'nyemaqen tectonic belt, which are 555±9 Ma and 493±6 Ma, respectively. The trace element geochemical features of the Kuhai gabbro and the Dur'ngoi diorite are similar to those of ocean island basalts (OIB) and island arc basalts (IAB), respectively. Thus, the Kuhai gabbro with the age of 555±9 Ma and OIB geochemical features is similar to the Yushigou oceanic ophiolite in the North Qilian orogen, whereas the Dur'ngoi diorite with the age of 493±6 Ma and IAB geochemical features is similar to the island arc volcanic rocks developed in the north Qaidam. The Late Neoproterozoic to Early Ordovician ophiolite complex in the area of Kuhai-A'nyêmaqên suggests that the southern margin of the "Qilian-Qaidam-Kunlun" archipelagic ocean in this period was located in the southern east Kunlun tectonic belt. Therefore, the southern east Kunlun tectonic belt in the early Paleozoic is not comparable to the Mianlüe tectonic belt in the Qinling orogenic belt.

关键词： Kunlun tectonic belt, zircon SHRIMP U-Pb dating, "Qilian-Qaidam-Kunlun" archipelagic ocean, ophiolite complex

Warming in Arctic intermediate and deep waters around Chukchi Plateau and its adjacent regions in 1999

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China Earth Sciences 2005年第8期48卷 1312-1320页

作者： ZHAO Jinping1, GAO Guoping2 & JIAO Yutian1 1. First Institute of oceanography, State oceanic Administration, Qingdao 266061, China 2. ocean University of China, Qingdao 266003, China 1. First Institute of oceanography State Oceanic Administration 266061 Qingdao China 2. ocean University of China 266003 Qingdao China

Based on the data measured during Arctic scientific expedition of China in 1999, the characteristics of temperature and salinity distributions around the Chukchi Plateau and its ad-jacent regions have been studied. It was found that the intermediate water with temperature higher than 0.5℃ existed in all parts of a 640 km section with a maximum temperature of 0.85℃ indicating a strong signal of the warming in Arctic Intermediate Water in 1999. Two important phenomena are described in this paper. First, the temperature of warm water was horizontally nonuniform. In the area of Chukchi Plateau, the temperature was higher, the layer of warm water was thicker and the depth of the warm water core was shallower than those in the area of con-tinental slope. The horizontal nonuniformity of the temperature distribution of warming water im-plies that the upward heat flux should also be nonuniform, thus exerting different effects on sea ice thickness, ice extent, and air-sea heat exchange. The mechanism to generate higher tem-perature in the plateau region was the bypassing of current around the plateau area caused by the special local topography, which restricted water exchange across the plateau and conserved heat in the water body. Second, the deep water down to 1400 m was also warming with a tem-perature increase of 0.2℃. The warming in deep water reflects the occurrence of complicated heat redistribution processes in the intermediate water, which altered the thermal structure in the upper 1400 m. The warming data embody the obvious impact of global climate change on the Arctic ocean and further studies are wanted.

关键词： Chukchi Plateau, Arctic ocean, warming in intermediate water, warming in deep water.