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1.
近百年中国北方沿海地区气温年代际变化及趋势预测 总被引：1，自引：0，他引：1
《海洋湖沼通报》2015,(3)
以青岛为例,利用近百年的月平均气温资料,通过统计的方法分析了中国北方沿海地区四季气温变化,分析了气温年代际变化与太平洋海温以及太平洋海温年代际振荡(PDO)的关系,着重分析了气温正负位相年北半球平均环流形势和海平面气温。最后利用CMIP5模式数据预测青岛气候未来的变化趋势。结果表明:中国北方近海地区气温呈上升趋势,冬季温度上升幅度最大,夏季升温最小,气温变化与附近海域海温显著相关。各季节气温有年代际和50a变化周期,在年代际变化周期上与PDO周期有较好的同期和滞后相关性,春季和夏季尤为明显。青岛气温正负位相年平均环流形势明显相反,并且与北半球海平面气温异常联系紧密。全球变暖背景下,未来青岛气温仍将持续上升。 相似文献
2.
西太平洋暖池海温异常年夏季东亚大气环流特征 总被引：3，自引：0，他引：3
利用NCEP/NCAR逐月再分析资料对西太平洋暖池区海表水温冷、暖异常年夏季东亚大气环流作了合成分析,与气候平均比较后发现:夏季暖池区暖异常时,在西太平洋上空的对流层低层产生一个强的反气旋偏差环流,因而不利于南海南部和赤道太平洋地区的西风发展,使热带夏季风强度减弱;在南海西部和中南半岛东部有偏差气流转向大陆,因而增强了偏南风,使副热带夏季风强度增强;在对流层中、下层副高脊线位置偏南,大约以400hPa为分界线,低层副高强度增强,高层副高强度减弱。西太平洋暖池冷异常年夏季东亚大气环流特征大致与上述情况相反,且强度或变化幅度小于暖异常年夏季。另外,与气候平均比较,暖异常年纬向Walker环流上升支大幅西移,而冷异常年该环流上升支则东移。 相似文献
3.
《海洋预报》2015,(6)
利用国家气候中心提供的中国160站逐月气温数据集、NCEP/NCAR再分析数据中心提供的大气环流数据、NOAA提供的全球海表温度数据及美国冰雪中心的海冰数据,分析了1951—2011年我国冬季气温异常的时空变化特征。应用经验正交函数分解得到中国冬季气温变化的两种典型空间分布型态-全国一致型和南北相反型,三次样条函数拟合结果表明这两种分布型态均具有显著的趋势变化特征。同时,分别探讨了大气环流及外强迫因子的趋势变化及其对中国冬季气温变化趋势的影响,并综合分析了影响我国冬季气温趋势变化的海温(冰)等外强迫因子与东亚大气环流系统之间的相互配置及贡献。结果表明,强的热带海温异常变化是影响东亚大气环流及冬季气温变化的最主要外强迫因子。当热带印度洋与赤道中东太平洋海温同时偏高(低)时,冬季西伯利亚高压强度偏弱(强),AO处于正(负)位相,东亚冬季风强度偏弱(强),冬季气温呈一致偏高(低)变化;当热带印度洋海温偏高(低),赤道中东太平洋海温偏低(高)时,东亚冬季风强度偏弱(强),AO指数为负(正)位相,西伯利亚高压偏弱(强)的配置时,冬季气温易呈北冷(暖)南暖(冷)趋势变化。 相似文献
4.
对2种东亚夏季风指数进行了对比分析，选择1种能较好地表征山东夏季降水的夏季风指数。研究了山东旱涝年以及强弱季风年500hPa高度场、850hPa风场、热带洋区OLR场、西太平洋副热带高压等异常分布特征，并初步探讨了影响山东夏季降水的物理机制。结果表明，海陆热力差指数是1种较适合研究山东夏季降水的东亚夏季风指标。强（弱）指数年，南海．热带西太平洋地区对流活动较常年偏强（弱），热带东太平洋地区对流活动偏弱（强），walker环流偏强（弱），北半球500hPa环流形势呈EAP（负EAP）遥相关型，副热带高压偏北偏强（偏南偏弱），山东夏季以多雨（少雨）年份居多；春夏季南海．热带西太平洋地区对流活动与山东夏季降水之间存在着遥相关关系，两者遥相关的可能机制是热带强迫所激发的大尺度准定常Rossby波的传播。 相似文献
5.
山东省东接太平洋，西连欧亚大陆，受海洋和大陆的影响，季风气候特点相当显著，常导致严重旱、涝灾害。山东全年降水主要集中在夏季，6~8月降水占全年降水的60%以上。其原因主要是受西太平洋副热带高压和夏季风活动的影响。副热带高压的增强和北伸与梅雨锋的位置和强度变化对山东夏季降水有直接作用，其夏季降水的年际变率较大，是旱、涝频发的省份。
我国旱涝变化与太平洋海洋热状况有着极为密切关系(翁学传等，1994)。El Nino现象对气候的影响更加引起了海洋气象学家对海洋变化的高度重视。他们分析了El Nino现象和太平洋海表温度(SST)与山东夏季降水的关系(如:奚秀芬，1988；卢金墀，1982；张苏平等1999)，但对比降水分布发现无论是 El Nino发生的当年还是次年，降水距平百分率的零线均从山东中部通过。我国夏季降水主要受三种类型雨带控制。由于山东处于一类雨带(华北多雨)和二类雨带(江淮多雨)的转换地带，近40年的降水资料分析表明，三种类型雨带在山东夏季降水正、负距平年出现率几乎均等。因此，山东夏季降水的变化有其特殊性，需要从多方面进行研究。
西太平洋暖池是全球海温最高的海域，也是全球海气能量交换总量最大的区域。它的存在和变化对北半球夏季气候异常有着重要作用。西太平洋副热带高压的变化与西太平洋暖池面积大小有密切关系(李万彪等，1998)，20世纪70年代末以来的西太平洋副高增强也与这一时期暖池的跃变有关(赵永平等，2002)，暖池及其上空的对流活动的异常影响着西太平洋副高的变化和我国雨带的位置(黄荣辉等，1992，1994)，由此所激发的大气遥相关波列可波及西欧和北美。最近的研究也表明，冬、春季暖池区热含量的变化对南海夏季风爆发早、晚有重要影响(Chen et al.，2001)。当西太平洋暖池区海洋热含量高时，南海夏季风爆发早，反之则爆发晚。这对我国夏季季风雨的变化研究有重要意义，而且也必将对山东夏季旱涝产生重要影响。
本文作者通过对山东夏季降水资料的分析，对山东夏季降水时空变化及其与西太平洋暖池区域海洋热状态及副热带环流和夏季风变化的关系和影响的可能过程进行了探讨。 相似文献
6.
利用1951—2013年山东122个气象观测站资料,分析山东冬季气温演变特征以及异常冷暖年相对应的大气环流异常。结果表明:山东冬季气温的年代际变化特征明显,冬季变暖的时间是从20世纪80年代中期开始,突变年为1986年;冬季异常冷暖年,乌拉尔山高压脊存在明显差异;在500 h Pa高度距平场上欧亚大陆呈反位相分布,异常冷年极强负距平中心位于贝加尔湖附近,山东处于负距平区底部;异常暖年,正距平中心位于巴尔喀什湖附近,山东处于正距平中。另据分析,冬季拉尼娜事件发生,和山东冬季气温偏冷有较好的关联性;并发现冬季气温与前期7月Nino3区海温正相关最好。 相似文献
7.
太平洋-印度洋暖池次表层水温与南海夏季风爆发 总被引：3，自引：0，他引：3
为探索太平洋—印度洋热带海域次表层水温对南海季风的影响，用Argo剖面浮标等实测资料，分析了太平洋—印度洋暖池次表层水温异常对南海夏季风爆发的影响。结果表明：冬季，太—印暖池次表层水温偏暖（冷）时，翌年南海夏季风爆发时间偏早（晚）是主要现象。太—印暖池次表层水温偏暖，可能引起Walker环流加强，西太平洋副热带高压偏弱，中心位置偏北偏东，南海和西太平洋上空对流层下层有气旋性距平环流出现，有利于低空西到西南气流的加强，导致南海夏季风爆发偏早；太—印暖池次表层水温偏冷，可能引起Walker环流东移并减弱，西太平洋副热带高压偏强，中心位置偏南偏西，南海和西太平洋上空对流层下层有反旋性距平环流出现，不利于低空西到西南气流的加强，导致南海夏季风爆发偏晚。结论：冬季，太—印暖池次表层水温偏暖（冷），翌年南海夏季风爆发时间偏早（晚）是主要现象。 相似文献
8.
《海洋气象学报》2017,(4)
使用1951年以来66 a的观测和再分析资料,通过合成分析的方法对比分析了厄尔尼诺/拉尼娜(El Nio/La Nia)伴随正/负印度洋偶极子(positive/negative Indian Ocean Dipole,pIOD/nIOD)发生年或独立发生年山东夏、秋季气温和降水的年际变化特征,结果表明,伴随IOD型和独立型El Nio/La Nia对山东夏、秋季气温和降水的影响在强度、范围、正负位相、空间型态上存在很大的差异。在气温方面,El Nio在p IOD的调制作用下对山东南部地区夏季气温年际变化的影响加强;El Nio与p IOD伴随发生时,山东秋季气温较常年偏高,而独立发生时气温则偏低,呈反位相变化;La Nia与n IOD伴随发生年夏季鲁西北气温较常年偏低,La Nia独立发生年夏季半岛东部气温较常年偏高,气温异常呈反位相变化;nIOD对La Nia的调制促进作用有利于山东秋季气温较常年异常偏高;850 h Pa气温异常与山东表面气温异常有很强的正相关关系。在降水方面,El Nio在pIOD的调制作用下容易引起山东北部地区夏季降水偏少,但会削弱其对山东中部地区秋季降水负异常的影响;La Nia在n IOD的调制作用下山东境内降水都较常年偏多,但降水异常地域分布非常不均,鲁西北降水较常年显著偏多;独立型La Nia更易引起鲁西北西部、鲁中、鲁南大部分地区夏季降水偏少。850 h Pa环流异常配合温度场异常对山东夏、秋季降水异常分布有一定的影响。 相似文献
9.
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
10.
根据1949~1998年期间8次显著El Nio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 Nio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 Nio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 Nio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 Nio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 Nio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
11.
Arne Schnack-Friedrichsen Angela M. Davis Jim D. Bennell Dei G. Huws 《Marine Georesources & Geotechnology》2001,19(4):221-243
The interdependence between the seismo-acoustic properties of a marine sediment and its geotechnical/physical parameters has been known for many years, and it has been postulated that this should allow the extraction of geotechnical information from seismic data. Though in the literature many correlations have been published for the surficial layer, there is a lack of information for greater sediment depths. In this article, a desktop study on a synthetic seafloor model illustrates how the application of published near-surface prediction equations to subsurface sediments (up to several tens of meters burial depth) can lead to spurious predictions. To test this further, acoustic and geotechnical properties were measured on a number of sediment core samples, some of which were subjected to loading in acoustically-equipped consolidation cells (oedometers) to simulate greater burial depth conditions. For low effective pressures (representing small burial depths extending to around 10 meters subsurface), the general applicability of established relationships was confirmed: the prediction of porosity, bulk density, and mean grain size from acoustic velocity and impedance appears generally possible for the investigated sedimentary environments. As effective pressure increases through, the observed relationships deviate more and more from the established ones for the near-surface area. For the samples tested in this study, in some instances increasing pressure even resulted in decreasing velocities. There are several possible explanations for this abnormal behavior, including the presence of gas, overconsolidation, or bimodal grain size distribution. The results indicate that an appropriate depth correction must be introduced into the published prediction equations in order to obtain reliable estimates of physical sediment properties for greater subsurface depths. 相似文献
12.
Shigehisa Nakamura 《Marine Geodesy》2000,23(1):55-61
Specific properties of the interannual sea level variations and annual tides in the Northwestern Pacific were studied. Several tide stations were monitored. The monthly mean sea level for the year of 1995 was analyzed at each tide station. A seismic event in 1995, some tectonic activity around the subject area, and the Kuroshio (the oceanic western boundary current) may possibly contaminate results which would have occurred from the astronomical annual tide alone. 相似文献
13.
The effect of different fixation and storage protocols on the flow cytometric (FCM) simultaneous analysis of bacterioplankton and phytoplankton in coastal seawater samples (Mediterranean coastal lagoons) was investigated. FCM measurements (cell number, fluorescence and scatter characteristics) were obtained through DAPI staining. Three fixatives [glutaraldehyde (GA), formaldehyde (FA) and paraformaldehyde (PFA)] and two storage (3 months duration) methods (5 °C and −196 °C) were tested. Two dominant populations were detected in studied samples: bacteria and eukaryotic picophytoplankton. Adding fixatives (2% final concentration) appears necessary to obtain FCM exhaustive counts of all the bacteria and phytoplanktonic cells. This was related to the permeation effect of fixatives which allowed a better DAPI staining of the cells. Maximum fluorescence, i.e. optimal staining of the cells was obtained with FA or PFA, and significant lower fluorescences with GA. Fixed samples stored at 5 °C induced rapid cell loss. Only storage in liquid nitrogen of samples fixed with FA or PFA, allows mid-term (≥4 months) preservation of bacteria or picophytoplankton cell numbers, and limited evolution of DAPI-induced fluorescence and scatter characteristics. 相似文献
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15.
《海洋学报(英文版)》2014,(9):F0003-F0003
<正>Acta Oceanologica Sinica(AOS)is a comprehensive academic journal edited by the Editorial Committee of Acta Oceanologica Sinica and is designed to provide a forum for important research papers of the marine scientific community which reflect the information on a worldwide basis.The journal publishes scholarly papers on marine science and technology,including physics,chemistry,biology, 相似文献
16.
The relationship between the flux of exotic benthic foraminiferal tests (i.e. tests which are supplied from open-sea sources alone) in a tidal inlet and that of bulk sediment was analysed, which can be expressed as two first-order linear equations. According to this relationship, in order to determine net sediment transport directions in the entrance, the test concentration in surficial sediments of the tidal basin can be compared against a ‘ critical level ’. The critical level is determined for the conditions that no net transport of bulk sediment is present within the entrance. If the observed concentration (averaged over the tidal basin) is higher than the simulated critical level, then the net sediment transport is directed to landward. This method is applied to the analysis of net sand transport at Christchurch Harbour, a tidal inlet system located in southern England. In this investigation, concentrations of exotic foraminiferal tests in the surficial sediments of the tidal basin and ebb tidal delta area were obtained from the analysis of sea-bed sediment samples. A series of probable critical levels were calculated based upon the data sets with regard to: (1) sediment discharge from the rivers; (2) magnitude of sediment discharge within the entrance during the ebb; (3) the test concentration outside the harbour; (4) the thickness of the moving layer; and (5) two parameters associated with dispersive processes. The results show that the concentration in the tidal basin sediment is higher than a number of simulated critical concentrations for representative cases. Consequently, the high level of the concentration of exotic benthic foraminiferal tests within the harbour should be explained as a result of landward net transport of sands within the entrance. 相似文献
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18.
Coastal inundation associated with extreme sea levels is the main factor which leads to the loss of life and property whenever a severe tropical cyclonic storm hits the Indian coasts. The Andhra and Orissa coasts are most vulnerable for coastal inundation due to extreme rise in sea levels associated with tropical cyclones. Loss of life may be minimized if extreme sea levels and associated coastal flooding is predicted well in advance. Keeping this in view, location specific coastal inundation models are developed and applied for the Andhra and Orissa coasts of India. Several numerical experiments are carried out using the data of past severe cyclones that struck these regions. The simulated inland inundation distances are found to be in general agreement with the reported flooding. 相似文献
19.
Hoi-Soo Jung Kap-Sik Jeong Yong-Shik Chu Sung-Hyun Park Ki-Hyune Kim 《Marine Georesources & Geotechnology》2001,19(3):181-195
Grain size and water content in box-core sediments from the Clarion-Clipperton fracture zone (C-C zone) in the northeast equatorial Pacific were analyzed in detail to understand the downcore variations across a hiatus between Quaternary and Tertiary layers. Grain-size distributions in the topmost core sediments show two modes: a coarse mode (peaked at 50 μm) and a fine mode (at 2-25 μm). The coarse mode disappears gradually with depth accompanied by the dissolution of siliceous fossil tests, whereas the fine mode coarsens due to the formation of authigenic minerals. Water content increases abruptly across a color boundary between an upper pale brown layer and a lower dark brown layer that is the hiatus between Quaternary and Tertiary layers. Abundant smectites and microvoid molds, which are created by the prolonged fossil dissolution in the underlying sediment, are attributed for the abrupt downcore variation of water content. Overall variations in grain size and water content in the topmost core sediments in the western C-C zone are possibly constrained by the dissolution of biogenic siliceous fossils. Variations in geotechnical properties related to these changes must be considered in the design of nodule collectors. 相似文献
20.
Shigehisa Nakamura 《Marine Geodesy》2001,24(1):27-33
This article concerns an interrelation between the sea levels and the western boundary flow near a tectonic boundary in a local zone in the Northwestern Pacific. In this zone, sea level variations at stations located on the coast facing the Pacific are studied to find the interrelation between variations of the Kurosio flow as an index of the distance of the flow axis off a specific coast. The result is discussed after data processing of the monthly means of the sea levels, and a notice is taken of variations caused by active crustal upheavals during a seismic event, a local earthquake. 相似文献