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1.
I~IOXThe bulk tranSfer method, direct measurement or gradient measurement method are usuallyused for the flux observation and calculation. These methods provide the flux values only in thelOCation where the measurements are carried out. In recent years scientists began to use medelcombined with remote sensing data for the calculation of heat flux. Its main poverty is tO obtainthe flux distribution over the wide ocean area simultaneously. Li Shiming et al. (1997) analyzedthe sensible and la…  相似文献   

2.
In this paper the authors cite the aerosol samples collected with a KA-200 Anderson cascade Impactor and a KB-120 sampler during the first cruise of the Kuroshio investigation operated by the People's Republic of China and Japan cooperative program, from July 23 to August 21, 1987. The concentration size distributions and composition of marine aerosols over the Kuroshio area are analyzed. Neutron activation analysis is used to determine the elemental composition of the aerosols. The authors also discuss some characteristics of marine aerosols relating to long-range transport of crustal and anthropogenic elements from the continent to the remote ocean. Analytical results indicate that elements Al, Fe, Sc and Sb over this area are obviously influenced by the continent of Asia, and the size distributions are changed after long-range transport. The concentration of large particles increase. The concentrations of the elements C1 and Na are closely related to ocean conditions; the source of the elements Cl an  相似文献   

3.
The Fukushima nuclear accident in 2011 released large amounts of radionuclides, including ~(137)Cs, into the Pacific Ocean. A quasi-global ocean radioactive transport model with horizontal grid spacing of 0.5°×0.5° and 21 vertical layers was thereafter established to study the long-term transport of the Fukushima-derived ~(137)Cs in the ocean.The simulation shows that the plume of ~(137)Cs would be rapidly transported eastward alongside the Kuroshio Current and its extensions. Contaminated waters with concentrations lower than 2 Bq/m3 would reach the west coast of North America 4 or 5 years after the accident. The ~(137)Cs tends to be carried, despite its very low concentration, into the Indian and South Pacific Oceans by 2016 via various branches of ocean currents.Meanwhile, the ~(137)Cs concentrations in the western part of the North Pacific Ocean decrease rapidly with time. Up to now the highly contaminated waters have remained in the upper 400 m, showing no evidence of significant penetration to deeper layers.  相似文献   

4.
太平洋海域海气热通量地理分布和时间变化的研究   总被引:6,自引:1,他引:6  
应用美国宇航局Goddard地球观测系统四维资料同化系统计算和分析了太平洋海域感热通量和潜热通量随时间的变化规律和地理分布特征.研究结果表明,太平洋西北部海域热通量有明显的季节性变化,其余海域这种现象不明显.在太平洋海域总是存在潜热通量最高值区域,而感热通量除冬季20°N以北海域数值稍高外,其余海域数值都很小,没有出现最高值区域.纬度不同热通量随经度的变化规律不同,经度不同,热通量随纬度的分布规律也不同,同时各断面热通量随纬度的分布趋势随季节而改变.  相似文献   

5.
I am deeply honored to have been selected as a recipient of the 1987 Okada Prize by the Oceanographical Society of Japan. The present paper reviews my work and recent studies of other investigators concerning mineral aerosol (dust) particles in the marine atmosphere over the Pacific Ocean. I would like to emphasize the importance of atmospheric deposition of continental substances to the ocean environment. From consecutive measurements of atmospheric dust concentrations and total deposition fluxes at 13 island stations in the Pacific Ocean, a strong seasonal transfort pattern of dust particles was found at most of the stations. High atmospheric dust concentrations occurred during the spring in both hemispheres. There was a latitudinal gradient in both the atmospheric dust concentration and flux, with the highest values observed at midlatitudes. When combined with observations of dust storms in Asia and isentropic trajectory analysis, it was clear that the dust over the central North Pacific was transported by the upper westerly winds from the arid desert regions in central and eastern Asia. Transport times were 1–2 weeks, and in some cases, atmospheric transport paths of over 10,000 km were observed. Infrequent short-term dust events contributed most of annual atmospheric dust flux to the open ocean. These sporadic inputs are major sources for both suspended mineral matter in the water column and the non-biogenic component of deep-sea sediments in the Pacific Ocean. The impact of atmospheric dust fluxes on chemical and biological processes in the water column remains to be determined.  相似文献   

6.
本文使用SODA(simple ocean data assimilation)海洋同化资料,系统分析了厄尔尼诺-南方涛动(El Ni?o-Southern Oscillation,ENSO)循环中冷暖位相期间热带太平洋上层海洋环流的演变规律,探讨了形成海洋环流异常的新机制。结果表明,在厄尔尼诺成熟期,热带中东太平洋赤道潜流最弱,赤道两侧出现反气旋性环流异常;西太平洋赤道外热带海域出现气旋性环流异常,该区南、北赤道流、棉兰老流、黑潮、新几内亚沿岸潜流及南赤道逆流增强;北赤道逆流区出现异常气旋性环流串,北赤道逆流接近正常。在厄尔尼诺衰退期和拉尼娜发展期,热带中西太平洋赤道潜流达到极强,赤道两侧出现气旋性环流异常;西太平洋赤道外热带海域异常环流减弱,该处主要流场的强度减弱或处于正常状态;北赤道逆流区反转为异常西向流。结果表明, ENSO循环期间的上层海洋环流异常受到热带太平洋温跃层深度异常产生的压强梯度力异常调控,在赤道外热带海洋温跃层深度异常和科里奥利力共同作用产生大尺度海洋环流异常,而在赤道海域,海洋温跃层深度异常和Gill效应造成赤道潜流异常以及关于赤道对称的气旋或反气旋性环流异常。  相似文献   

7.
崔伟  王伟  马毅  杨俊钢 《海洋学报》2017,39(2):16-28
本文利用22年的AVISO卫星高度计融合数据,基于WA涡旋自动识别方法对西北太平洋的中尺度涡进行了识别追踪,并统计分析了研究区域中尺度涡的空间分布特征、运动属性以及季节和年际变化。研究结果表明:22年间共追踪到生命周期超过30 d的气旋涡3 841个,反气旋涡2 836个,气旋涡数量多于反气旋涡。涡旋大部分向西移动,西向传播的涡旋分布在整个研究区域,而东向传播的涡旋则集中在黑潮及其延伸区。涡旋主要存在15°~30°N的纬度带间;分别而言,气旋涡主要分布在研究区域的北部和南部,而反气旋涡主要分布在副热带逆流区。30°~35°N之间的黑潮延伸区具有明显更高的涡动能和涡振幅,与同纬度区域相比这里的涡旋半径也较高。在季节和年际变化上,春季出现的中尺度涡最多,夏季最少;对涡旋的月生成数目与ENSO指数MEI比较发现,西北太平洋涡旋活动变化并不直接与ENSO现象相关。  相似文献   

8.
1Introduction Sulfurisoneofthemostimportantelements whosebiogeochemicalcyclesarepivotaltotheatmo- sphericenvironmentandtotheclimaticchanges.The predominant,stablechemicalspeciesofsulfurinthe atmosphereissulfuricacidorsulfatewhichunderor- dinaryconditionsexistsmainlyinsmallaerosolparti- cles(Chinetal.,1996;Kerminenetal.,2000;Restadet al.,1998).Sulfuricacidorsulfate-dominatedaerosols areubiquitousintheloweratmosphere.Inthemarine boundarylayer(MBL),non-sea-saltsulfuricacidorsulfate(nss-SO42-)…  相似文献   

9.
-Mainly on the basis of the data obtained during PRC/US bilateral TOGA cruises, abnormal variation occurred during the 1986/1987 El Nino is shown in this paper about the thermal structure and circulation of the upper western tropical Pacific Ocean. The effects of the abmormal variation on the subtropical high over the Northwest Pacific Ocean are discussed. During the El Nino: (1) In the east part of the western tropical Pacific Ocean (the subsurface temperature data on the 165° E section are taken as an example), the water wanner than 29 C in the upper layer spread on the longitudinal section and positive temperature anormalies appeared in a large area of the sea surface. (2) In the west part of the western tropical Pacific Ocean (the subsurface temperature data on the 137°E section are representative ), the cross section occupied by the upper layer warmer water ( T >28 ℃ ) became shrunk, and the sea surface temperature showed negative amomalies. (3) The eastward flows in the upper layer of the 165°  相似文献   

10.
11.
1Introduction CarboncyclingintheArcticOceanplaysanim- portantroletoglobalchange.Traditionally,marine productivityintheArcticOceanisthoughttobevery low,andthussomebiogeochemicalprocessessuchas particleexportandcyclingofnutrientsarenotsoac- tivebecauseofthembeingcoveredperenniallybyice, lowtemperatureandshorttimeofphotosynthesis (PlattandRao,1975).Afewpreviousestimatesof particulateorganiccarbon(POC)exportindicateda neglectablemagnitudeinthecentralArcticOcean (Baconetal.,1989).However,recen…  相似文献   

12.
Basing upon the total of 1,081 samples collected by a large plankton net (160 cm in mouth diameter) in the Pacific Ocean, the geographical and vertical distribution ofGonostoma gracile were studied. The species is distributed in the water masses of the Kuroshio, the Kuroshio Extension, the North Pacific Current, the Oyashio, the North Pacific Subarctic Water and the western North Pacific Central Water. The center of distribution lies in the Kuroshio area off Japan. Vertically, the species occurs between the depths of 200 and 1,000 m, mainly 300–700 m, both during daytime and at night. A part of population might come up to 0–200 m at night, although its biomass is negligibly small in comparison to that remaining in 300–700 m layer. Postlarvae are found in 300–700 m layer, mainly at 300–500 m, and apparently do not undertake diurnal vertical migration.  相似文献   

13.
Understanding of the temporal variation of oceanic heat content(OHC) is of fundamental importance to the prediction of climate change and associated global meteorological phenomena. However, OHC characteristics in the Pacific and Indian oceans are not well understood. Based on in situ ocean temperature and salinity profiles mainly from the Argo program, we estimated the upper layer(0–750 m) OHC in the Indo-Pacific Ocean(40°S–40°N, 30°E–80°W). Spatial and temporal variability of OHC and its likely physical mechanisms are also analyzed. Climatic distributions of upper-layer OHC in the Indian and Pacific oceans have a similar saddle pattern in the subtropics, and the highest OHC value was in the northern Arabian Sea. However, OHC variabilities in the two oceans were different. OHC in the Pacific has an east-west see-saw pattern, which does not appear in the Indian Ocean. In the Indian Ocean, the largest change was around 10°S. The most interesting phenomenon is that, there was a long-term shift of OHC in the Indo-Pacific Ocean during 2001–2012. Such variation coincided with modulation of subsurface temperature/salinity. During 2001–2007, there was subsurface cooling(freshening)nearly the entire upper 400 m layer in the western Pacific and warming(salting) in the eastern Pacific. During2008–2012, the thermocline deepened in the western Pacific but shoaled in the east. In the Indian Ocean, there was only cooling(upper 150 m only) and freshening(almost the entire upper 400 m) during 2001–2007. The thermocline deepened during 2008–2012 in the Indian Ocean. Such change appeared from the equator to off the equator and even to the subtropics(about 20°N/S) in the two oceans. This long-term change of subsurface temperature/salinity may have been caused by change of the wind field over the two oceans during 2001–2012, in turn modifying OHC.  相似文献   

14.
Using the air-sea data set of January, 1983 (the mature phase of the 1982/83 El Nino event), the net radiation on the sea surface, the fluxes of the latent and the sensible heat from ocean to the atmosphere and the net heat gain of the sea surface are calculated over the Indian and the Pacific Oceans for the domain of 35°N-35°S and 45°E-75°W. The results indicate that the upward transfer of the latent and the sensible heat fluxes over the winter hemisphere is larger than that over the summer hemisphere. The sensible heat over the tropical mid Pacific in the Southern Hemisphere is transported from the atmosphere to the ocean, though its magnitude is rather small. The latent heat flux gained by the air over the eastern Pacific is less than the mean value of the normal year. The net radiation, on which the cloud amount has considerable impact, is essentially zonally distributed. Moreover, the sea surface temperature (SST) has a very good correlation with the net radiation, the region of warm SST coinci  相似文献   

15.
Settling particles play an important role in transporting organic carbon from the surface to the deep ocean. It is known that major components of settling particles are biogenic silicates (opal), biogenic carbonate (CaCO3), lithogenic clays and organic matter. Since each component aggregates and/or takes in organic carbon, all of these components have the ability to transport particulate organic carbon (POC) to the interior of the ocean. In this study, sediment trap experiments were carried out in four areas of the western North Pacific (including a marginal sea). Factors are proposed that correlate the composition of settling particles with POC flux. Annual mean organic carbon fluxes at 1 km depth in the western North Pacific Basin, Japan Sea, Hidaka Basin and northern Japan Trench were found to be 14.9, 18.1, 13.0 and 6.6 mg/m2/day, respectively. Organic carbon flux in the western North Pacific was greater than that in the Eastern North Pacific (7.4), the Equatorial Pacific (4.2), the Southern Ocean (5.8) and the Eastern North Atlantic (1.8). In the western North Pacific, it was calculated that 52% of POC was carried by opal particles. Opal is known to be a major component even in the Eastern North Pacific and the Southern Ocean, and the opal fluxes in these areas are similar to those in the western North Pacific. However, the organic carbon flux that was carried by opal particles (OCopalflux) in the western North Pacific was greater than that in the Eastern North Pacific and the Southern Ocean. These results indicate that the ability of opal particles to transport POC to the deep ocean in the western North Pacific is greater than that in the other areas.  相似文献   

16.
利用一个斜压两层海洋模式解析地研究了赤道东、西太平洋对信风张弛的响应特征.研究表明:当赤道上空偏东信风张弛或转为西风时,由于打破了海洋原来的平衡关系,结果在赤道东、西太平洋的温跃层附近产生了扰动并开始传播.西太平洋温跃层附近的扰动向东传播的速度远大于东太平洋扰动向西传播的速度,而且与东太平洋温跃层扰动向西传播的狭窄范围和小振幅相比,西太平洋温跃层扰动向东传播的范围和强度均很大.这与最近几次强厄尔尼诺增暖事件暖水从赤道西太平洋向赤道中、东太平洋的迅速传播特征是一致的.  相似文献   

17.
吕宋海峡西部深海盆内孤立波潜标观测研究   总被引:2,自引:0,他引:2  
Using a net surface heat flux (Qnet) product obtained from the objectively analyzed air-sea fluxes (OAFlux) project and the international satellite cloud climatology project (ISCCP), and temperature from the simple ocean data assimilation (SODA), the seasonal variations of the air-sea heat fluxes in the northwestern Pa cific marginal seas (NPMS) and their roles in sea surface temperature (SST) seasonality are studied. The seasonal variations of Qnet, which is generally determined by the seasonal cycle of latent heat flux (LH), are in response to the advection-induced changes of SST over the Kuroshio and its extension. Two dynamic regimes are identified in the NPMS: one is the area along the Kuroshio and its extension, and the other is the area outside the Kuroshio. The oceanic thermal advection dominates the variations of SST and hence the sea-air humidity plays a primary role and explains the maximum heat losing along the Kuroshio. The heat transported by the Kuroshio leads to a longer period of heat losing over the Kuroshio and its Extension. Positive anomaly of heat content corresponds with the maximum heat loss along the Kuroshio. The oceanic advection controls the variations of heat content and hence the surface heat flux. This study will help us understand the mechanism controlling variations of the coupled ocean-atmosphere system in the NPMS. In the Kuroshio region, the ocean current controls the ocean temperature along the main stream of the Ku roshio, and at the same time, forces the air-sea fluxes.  相似文献   

18.
西风爆发、次表层暖水东移与厄尔尼诺现象   总被引:7,自引:2,他引:7       下载免费PDF全文
利用最近20 a的大气海洋资料,分析了厄尔尼诺事件与赤道太平洋西风异常以及赤道太平洋次表层海温之间的关系.结果表明,赤道西太平洋(5°S~5°N,120°~160°E)和赤道中东太平洋(5°S~5°N,160°E~160°W)西风异常都存在着与厄尔尼诺周期一致的年际变化,但前者还包含有显著的2~3个月季节内振荡.赤道西太平洋次表层冷暖水东移也呈现年和年际时间尺度的振荡周期.在厄尔尼诺发生前,赤道西太平洋次表层海水出现持续性增暖,赤道西太平洋西风异常频率加快,强度增强.随后赤道中太平洋(160°E~160°W)出现持续性(3个月以上)强西风异常(即西风爆发),并进一步向东扩展,同时次表层暖水沿着赤道波导东移到赤道东太平洋混合层,导致赤道东太平洋海表大面积异常增暖,形成一次厄尔尼诺现象.最后,模式模拟了1980~1984年赤道太平洋海温的变化,进一步证实了赤道纬向西风异常对暖水东移起着重要的作用.  相似文献   

19.
中国近海大气气溶胶的时间和地理分布特征   总被引:26,自引:5,他引:21  
刘毅  周明煜 《海洋学报》1999,21(1):32-40
通过对中国近海10个航次气溶胶观测资料的统计分析得出:(1)从黄海、东海至日本以南海域气溶胶中地壳元素年平均浓度明显减小,在春季尘暴多发期间地壳元素浓度离到岸距离接指数规律递减.污染元素气溶胶浓度分布与陆源排放量和离岸距离有一定关系.(2)海上陆源气溶胶浓度的季节分布为:春季最大,秋冬次之,夏季最小.受日本排放源的影响,日本以南海域污染元素浓度最大值出现在冬季.(3)Se元素浓度与海洋源密切相关.海盐元素从黄海、东海至日本以南海域浓度逐渐增加,主要受周围海况影响,与风速呈现一定程度的正相关.影响近海气溶胶浓度的主要因素有陆源气溶胶排放量、降水分布和大尺度天气形势.  相似文献   

20.
冬季北太平洋西部上层海洋的热量输送   总被引:1,自引:2,他引:1  
用海气界面净热量收支和1950-1979年表层水温资料,计算了冬季北太平洋西部上层海洋热通量散度场,指出冬季北太平洋西部黑潮将大量低纬暖水输送到中高纬度海域,在30-35°N最大;亲潮将极地冷水沿千岛群岛向南输送,在45-50°N最大;两者在40°N附近相遇,混合减弱后沿纬向东传。同时用EOF分析方法对热通量散度距平场分型,前3个主要型分别为:黑潮亲潮偶合型、北太平洋海流型和冷平流优势型。最后还揭示了第一主要型与北太平洋副热带高压之间有意义的相关关系。  相似文献   

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