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Field biological and geomorphological observations in certain East Asia coasts permit definition of Mean Sea Level (MSL) with an accuracy of ∼10 cm, that is, a vertical geodetic datum, as well as recognition of the MSL of fossil shorelines, up to a few thousand years old, mainly associated with tectonic/seismic effects. Subsidence produced by compaction of nearly-surficial strata seems also to be a usual effect. These data indicate that datum variability is a widespread effect in East Asia, time-dependent even at time scales affecting engineering works, but only in a few cases fully predictable. 相似文献
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中国近海海平面变化研究进展 总被引：9，自引：0，他引：9
于宜法 《中国海洋大学学报(自然科学版)》2004,34(5):713-719
回顾和总结了近年来有关我国近海地区海平面变化的研究进展。综述了海平面变化的原因，海平面资料获取手段的发展，分析研究海平面变化的方法和模型以及海平面上升速率方面的主要成果；简要介绍了海平面均衡基准订正的意义和主要结论；阐述了1985国家高程基准研究工作和成果。 相似文献
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Sea level in the vicinity of Miami, Florida, is from three separate time series: Miami Beach (1932–1980), Haulover Pier (1982–1992), and Virginia Key (1994-present). In order to calculate the ensemble trend in Miami mean sea level (MSL), the three records must be merged with respect to the North American Vertical Datum of 1988. Because NAVD88 minus accepted MSL varies for the stations, the differences are treated as datum shifts, and are corrected accordingly. Thus adjusted, Merged Miami Sea Level (1932–2013) has a linear trend of 23.4 ± 1.3 cm/century, and along with logarithmic and polynomial least-squares fits, all three having a variance explained (r2 × 100) of 82.4%. 相似文献
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四个耦合模式在模拟和预测东亚季风系统方面的对比分析 总被引：2，自引：1，他引：1
基于政府间气候变化专门委员会(IPCC)第四次评估报告(AR4)中的海气耦合模式实验,本文研究了温室气体辐射强迫达到4.5 W/m2(Representative Concentration Pathways,RCP4.5)未来情景下东亚地区季风气候变化,对4个海气耦合模式(FGOALS_s2.0(Flexible Global Ocean-Atmosphere-Land System model_s2.0)、GFDL_CM3(Geophysical Fluid Dynamics Laboratory Coupled Model v3)、MPI_ESM_LR(Max Planck Institute-Earth System Model-Low Resolution)和MIROC5(Model for Interdisciplinary Research on Climate v5))的模拟结果进行了对比。结果显示,各模式均能较好地模拟东亚地区的季风气候态特征,例如冬、夏季盛行风向,降水、热通量的季节和海陆分布特点及降水北进南撤特征。然而,各模式的模拟结果之间也存在差异,例如与再分析资料相比,FGOALS_s2.0模拟的风速偏大,GFDL_CM3模拟的降水较低,综合比较得出,GFDL_CM3对东亚地区气候变化的模拟效果最好。对未来气候的预测方面,4个模式给出较为一致的结论:未来100 a东亚季风的总体变化趋势为季风环流夏季风增强,冬季风减弱,夏季风速增加3.7%左右;降水增加,尤以陆地增加明显,东亚地区未来降水全年增加量约为4.62%;大部分地区热通量有增加的趋势,这是温室效应增强的结果。 相似文献
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利用第六次国际耦合模式比较计划（Coupled Model Intercomparison Project Phase 6, CMIP6）中的两组子试验,结合线性斜压模式模拟的结果,研究了近年来亚洲内部出现的东亚减少、南亚增加的偶极子型人为气溶胶排放变化调控亚洲夏季风响应的特征及物理机制。对东亚夏季风而言,在考虑海洋-大气耦合作用的气候系统总响应中,东亚夏季风环流和降水显著地加强;在不考虑海洋调控作用的大气直接响应过程中,东亚人为气溶胶排放减少导致的陆地升温使得海陆温差增大,进而通过引起东亚陆地上的气旋式环流异常加强东亚夏季风环流和降水。对南亚夏季风而言,其在偶极子型人为气溶胶强迫下呈现出更为复杂的变化特征。在大气直接响应过程中,人为气溶胶强迫引起的海陆热力差异变化导致南亚夏季风环流减弱、降水减少。在考虑海洋-大气耦合过程的总响应中,南亚夏季风环流表现出微弱增强,同时印度次大陆的南亚夏季风降水也出现增多的异常变化。这表明,局地和海洋-大气动力耦合过程在区域气候对人为气溶胶强迫的响应中扮演着非常重要的角色。此外,通过线性斜压模式发现,东亚和南亚局地的人为气溶胶强迫导致的大气加热场异常不仅能影响局地的夏季风环流,还可以通过引起大范围的表面气压异常进而调控整个亚洲夏季风环流的变化。 相似文献
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南极威德尔海区域海冰异常对初夏东亚大气环流和天气影响的数值研究 总被引：5，自引：2，他引：3
利用经过改变用于长期数值预报的CCM1(R15L7)模式以1975年1月16日00Z模式适应场为初始场积分5个月,研究南极威德尔海附近(60°W～30°E)海冰的面积异常对东亚初夏环流转换季节的影响.发现当南极海冰偏多时,在亚洲北部冷空气活动在初夏仍然很多,势力还很强,东亚南北两支急流分支仍很明显,各种环流特征更偏向于冬季型,不利于东亚初夏的环流季节转换.海冰异常偏少时则相反,亚洲北部的冷空气活动明显减弱,南方暖气流势力明显加强北移,东亚的两支急流也趋于合并北抬,环流形势更接近于夏季型,海冰的减少促进了东亚初夏的环流季节转换过程. 相似文献
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- The relationship between meridional wind in mid - latitudes of East Asia and SST in the Equatorial Eastern Pacific is analysed in this paper. It is pointed out that there exist close relations between the seasonal changes of the meridional wind in mid - latitudes of East Asia and SST in the Equatorial Eastern Pacific. The intensification of north winds over East Asia also plays an important role in the rise of SST in Equatorial Eastern Pacific one year later. The strong winter monsoon usually occurs in previous winter of El Nino and it causes low temperature to a great extent in China . The low temperature in China can be regarded as a precursor of El Nino. 相似文献
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The rise or fall trend of the sea level along the coast of East Asia is estimated with different computational methods based on sea‐level data of longer time series collected from 45 tide gauge stations there. The results show that the relative sea level, on average, has been rising along the coast of the whole of East Asia from the early 1950s to the early 1990s. The regional change of sea‐level rise or fall is greater. The sea level along the coast of China, except along the Shandong Peninsula, is rising; the sea level along the coast of the southern islands of Japan and the southern Korean peninsula, as estimated by several methods, is mostly rising, but the rate of rise is very small. The difference between the results estimated in this study and the corresponding results of Barnett along the coast of East Asia is significant. This is mainly because the number of the stations selected by Barnett is relatively small, and the selected stations are concentrated at the southern and northern ends of the region, without data in the middle of the region. The effect of the estimating methods is smaller. 相似文献
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El Niño对东亚气候年际异常影响的数值模拟 总被引：3，自引：0，他引：3
根据1949~1998年期间8次显著El Niño事件合成的24个月年际海温异常(SSTAs)和气候平均的海温(SST),利用CCM3分别进行了3个包含10次积分的集合试验,即控制试验(CTRL),热带太平洋海洋全球大气试验(TOGA)以及整个太平洋海洋全球大气试验(TOGA-NP),通过对比分析这3个试验之间的集合模拟结果,揭示了在El Niño不同演变阶段东亚气候年际异常响应结构以及北太平洋年际SSTAs在此过程中的调制作用.结果表明:El Niño发展阶段夏季,东亚地区大气环流异常呈显著的负PJ波列,副热带高压减弱、偏东,东亚夏季风增强,东北和江淮流域降水偏多,华北和长江流域及其以南地区降水偏少;El Niño成熟阶段冬季,东亚大槽加强,东亚北部冬季风加强,西太平洋副热带地区低层有显著的反气旋式异常风场,华南地区降水显著增多;El Niño衰亡阶段夏季东亚气候年际异常型与其发展阶段夏季几乎相反.同时,北太平洋年际SSTAs对El Niño影响东亚气候年际异常有一定的调制作用,使模拟的我国降水异常分布更符合观测. 相似文献
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The long-term time series analysis of the SST (sea surface temperature) in the Eastern Equatorial Pacific Ocean and the monthly MSL (mean sea level) in the tropical Pacific Ocean is conducted. Their quasiperiodic and low-frequency oscillation features are revealed. The significant periods of low-frequency fluctuations for monthly MSL in the area of 20°N-20° S are between 43. 5 months and 50. 0 months, approximating closely to 47. 6 months which is the significant period of SST in the Eastern Equatorial Pacific Ocean. From the results of space-spectral analysis, the low-frequency fluctations of monthly MSL in the tropical Pacific Ocean appear to have a anticlockwise circularly-propagating pattern, which is, the Eastern Pacific Ocean (off-shore of Mexico) →the area of NEC (North Equatorial Current) →the Western Equatorial Pacific Ocean→the area of NECC (North Equatorial Counter-Current)→the Eastern Equatorial Pacific Ocean. The phases of the pattern correspond to those of El Nino cycle. On the basis 相似文献
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A New Methodology for Incorporating Tide Gauge Data in Sea Surface Topography Models 总被引：1，自引：0，他引：1
As part of the Vertical Offshore Reference Frames (VORF) project sponsored by the U. K. Hydrographic Office, a new model for Sea Surface Topography (SST) around the British Isles has been developed. For offshore areas (greater than 30 km from the coast), this model is largely derived from satellite altimetry. However, its accuracy and level of detail have been enhanced in coastal areas by the inclusion of not only the 60 PSMSL tide gauges with long-term records around the coasts of the United Kingdom and Ireland but also some 385 gauges established at different epochs and for different observation spans by the U. K. Admiralty. All tide gauge data were brought into a common reference frame by a combination of datum models and direct GPS observations, but a more significant challenge was to bring all short-term sea level observations to an unbiased value at a common epoch. This was achieved through developing a spatial-temporal correlation model for the variations in mean sea level around the British Isles, which in turn meant that gauges with long-term observation spans could be used as control points to improve the accuracy of Admiralty gauges. It is demonstrated that the latter can contribute point observations of mean sea level (MSL) with a precision of 0.078 m. A combination of least squares collocation and interpolation was developed to merge the coastal point and offshore gridded data sets, with particular algorithms having to be developed for different configurations of coastal topology. The resulting model of sea surface topography is shown to present a smooth transition from inshore coastal areas to offshore zones. Further benefits of the techniques developed include an enhanced methodology for detecting datum discontinuities at permanent tide gauges. 相似文献
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西太平洋暖池热含量变化与东亚冬季风关系 总被引：1，自引：0，他引：1
利用 1955-2003 年 NCEP\NCAR 再分析资料和美国 Scripps 海洋研究所环境数据分析中心 ( JEDAC ) 提供的冬季热含量资料,采用小波分析、相关及合成分析等方法, 分析了西太平洋暖池热含量变化特征及其与东亚冬季风关系.结果表明,西太平洋暖池热含量与东亚冬季风有着非常密切的联系,当西太平洋暖池热含量异常偏高时,对流层低层在菲律宾及以东洋面形成一个异常的气旋性环流,中国大陆上空形成一个异常的反气旋性环流,从而使得东亚冬季风在东南区加强,西北区减弱. 相似文献
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东海虾类的生态群落与区系特征 总被引：6，自引：0，他引：6
有关东海的虾类，刘瑞玉(1959，1963，1964)、董聿茂(1959，1980，1986)等已做过大量的调查研究。近10多年来，由于东海传统的主要经济鱼类资源衰退，捕食虾类的鱼类减少，因此，使虾类生存空间扩大，这有利于虾类资源的繁衍生长，使虾类资源发生量增多，数量增长较快。东海区三省一市近几年虾类产量达到80×104~90×104t，其中浙江省为60×104~70×104t，拖虾作业已成为东海区一大作业方式，对促进海洋捕捞业的发展起重要作用。20世纪80年代中后期，我们开展了东海虾类资源开发调查，尔后又继续与拖虾生产船相结合进行监测调查，积累了一些资料，本文就东海虾类生态群落结构与区系特征进行探讨。 相似文献
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The present study evaluates future storm surge risk due to tropical cyclones (typhoons) in East Asia. A state-of-the-art atmospheric general circulation model (GCM) outputs are employed as the driving force for simulating storm surges associated with the projected changes in climate. The reproducibility of tropical cyclone (TC) characteristics from the GCM in the Northwest Pacific (NWP) is confirmed by comparing with the observed best track data, and future typhoon changes were presented. Storm surge simulation is carried out for East Asia, with the finest nested domain on the Japanese coast. The probability of maximum storm surge heights with specified return periods is determined using extreme value statistics. We show a strong regional dependency on future changes of severe storm surges. 相似文献
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Study of the major Asian rivers discharge to the ocean reveals variations of their water discharges and sediment loads.and local characteristics of river sediment concentrations.On the basis of this,the Asian rivers fall into three regions,including Eurasia Arctic,East Asia,Southeast and South Asia Regions.The Eurasia Arctic Region is characterized by the lowest sediment concentration and load,while the East Asia Region is of the highest sediment concentration and higher sediment load,and the South-East and South Asia Region yields Higher Sediment concentration and highest sediment load. The sediment loads of these regions are mainly controlled by climate,geomorphology and tectonic activity.The Eurasia Arctc rivers with large basin areas and water discharge,drain low relief which consists of tundra sediment,thus causing the lowest sediment load.The East Asia rivers with small basin areas and lowest water discharges,drain extensive loess plateau,and transport most erodible loess material,which results in highest sediment concentration.The SE and South Asia rivers originating from the Tibet Plateau have large basin areas and the largest water discharges because of the Summer Monsoon and high rainfall influence,causing the highest sediment load.In Asia,tectonic motion of the Tibet Plateau Plays an important role.Those large rivers originating from the Tibet Plateau trasport about 50% of the world river sediment load to ocean annually,forming large estuaries and deltas,and consequently exerting a great influence on sedimentation in the coastal zone and shelves. 相似文献
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Ole Baltazar Andersen Karina Nielsen Per Knudsen Chris W. Hughes Rory Bingham Luciana Fenoglio-Marc 《Marine Geodesy》2013,36(6):517-545
AbstractThe ocean mean dynamic topography (MDT) is the surface representation of the ocean circulation. The MDT may be determined by the ocean approach, which involves temporal averaging of numerical ocean circulation model information, or by the geodetic approach, wherein the MDT is derived using the ellipsoidal height of the mean sea surface (MSS), or mean sea level (MSL) minus the geoid as the geoid. The ellipsoidal height of the MSS might be estimated either by satellite or coastal tide gauges by connecting the tide gauge datum to the Earth-centred reference frame. In this article we present a novel approach to improve the coastal MDT, where the solution is based on both satellite altimetry and tide gauge data using new set of 302 tide gauges with ellipsoidal heights through the SONEL network. The approach was evaluated for the Northeast Atlantic coast where a dense network of GNSS-surveyed tide gauges is available. The typical misfit between tide gauge and satellite or oceanographic MDT was found to be around 9?cm. This misfit was found to be mainly due to small scale geoid errors. Similarly, we found, that a single tide gauge places only weak constraints on the coastal dynamic topography. 相似文献