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1.
Wang  LiBo  Yang  ZuoSheng  ZHang  RongPing  Fan  DeJiang  Zhao  MeiXun  Hu  BangQi 《科学通报(英文版)》2011,56(15):1588-1595
Sea surface temperature (SST) records in the South Yellow Sea during the last 6200 years are reconstructed by the unsaturation index of long-chain alkenones (K 37 U ’) in sediment core ZY2 from the central mud area.The SST records varied between 14.1 and 16.5°C (15.6°C on average),with 3 phases:(1) A high SST phase at 6.2-5.9 cal ka BP;(2) A low and intensely fluctuating SST phase at 5.9-2.3 cal ka BP;and (3) A high and stable SST phase since 2.3 cal ka BP.Variation of the SST records is similar to intensity of the Kuroshio Current (KC),and corresponds well in time to global cold climate events.However,the amplitude of the SST response to cooling events was significantly different in different phases.The SST response to global cooling event was weak while the KC was strong;and the SST response was strong while the KC was weak.The difference in amplitude of the SST response is possibly caused by the modulation effect of the Yellow Sea Warm Current which acts as a shelf branch of the KC and a compensating current induced by the East Asia winter monsoon.The warm waters brought by the Yellow Sea Warm Current cushion the SST decrease induced by climate cooling,and both the Kuroshio and East Asian winter monsoon play important roles in the modulation mechanism.The SST records display a periodicity of 1482 years.The same period was found in the KC records,indicating that variation of the SST records in the central South Yellow Sea is strongly affected by KC intensity.The same period was also found in Greenland ice cores and North Atlantic and Arabian Sea sediment cores,showing a regional response of marine environmental variability in the East China Seas to that in the global oceans.  相似文献   

2.
本文利用来自青岛附近海域1961~2009年的海表温度(SST——Sea Surface Temperature)资料,对该海域SST的变化趋势、突变形式、变化周期等进行分析。结果表明:(1)1961~2009年期间,青岛附近海域的SST以0.029℃/a的速度显著性线性递增;(2)青岛附近海域的SST存在明显的2.1~2.7年、3.8~5.0年的变化周期以及30年以上的长周期震荡;(3)青岛附近海域的SST存在明显的突变形势,且突变期为20世纪80年代末期至90年初期;逐夏季SST的突变期为1988年;逐冬季SST的突变期为1992年前后。  相似文献   

3.
运用相关分析和滑动相关方法,分析了江淮流域5个代表站1903-2000年梅雨期雨量的变化特征及其与太平洋海温的相关关系及年代际差异.结果表明,江淮地区梅雨期雨量在近百年来存在明显的年际和年代际变化特征.通过分析梅雨期雨量与太平洋海温的年代际相关特征发现,江淮流域梅雨期雨量与前期及同期太平洋海温关系密切,前一年冬季及梅雨期东北太平洋海温与江淮流域梅雨期雨量负相关,在热带东太平洋的Nino1 2区两者正相关显著,同年春季西太平洋部分海域海温与江淮流域梅雨期雨量正相关.从年际相关分析发现,前一年冬季太平洋海温与梅雨期雨量正相关,同年春季以及梅雨期两者相关不明显.通过分析年代际差异发现,江淮流域梅雨期雨量与前期及同期热带太平洋关键区海温的21a滑动相关存在显著的年代际差异,这种差异与海温的21a滑动平均的年代际冷暖背景关系密切,热带太平洋海温关键区前一年冬季冷海温背景下,梅雨期雨量同海温正相关显著,同年春季暖海温背景下,两者之间负相关显著,而江淮流域梅雨期雨量同中国近海海温之间(从冬季到梅雨期)维持显著的正相关,与该区海温冷暖背景的关系则并不明显.  相似文献   

4.
对采自南海西沙的3种不同种的现代砗磲(库氏砗磲、鳞砗磲、砗蚝)进行了高分辨率Sr/Ca比值分析.结果表明:库氏砗磲和鳞砗磲的Sr/Ca比值呈现出年周期变化并与实测的海表面温度(SST)形成较好的对应;而砗蚝的Sr/Ca比值年周期信号较弱且与温度的对应存在较大的不确定性.通过全年逐月或逐周对应和极端对应,我们共获得了两种砗磲的4个有效的Sr/Ca-SST方程,并能较好地作为Sr/Ca温度计进行温度恢复.对比不同种类的砗磲,其Sr/Ca分布有所不同,相应的Sr/Ca-SST方程也有一定的区别.这项研究为选择性地应用砗磲研究全新世气候变化提供了依据.  相似文献   

5.
Sea surface temperature over the past 450 ka was obtained by the unsaturation of molecular fossil-long chain alkenone with a resolution of about 1 ka from the western South China Sea. This is the longest temperature profile in the South China Sea at such high resolution. The U37^κ-SST results revealed similar glacial-interglacial cycles as the δ^18O profile of planktonic foraminifera, with SST variability of 23-25.5℃ for glacial and 25-28℃ for interglacial periods. The highest SST (28.4℃) was recorded at MIS5.5 and lowest SST (22.6℃) during MIS2. The SST record preceded the planktonic foraminiferal δ^18O on five glacial-interglacial transitions. Comparison of temperature records from the Southern and Northern Hemispheres indicated a more Southern Hemisphere-like pattern for the temperature variation in the SCS. Strong precession and semiprecession signals in the spectra of our SST record manifest the tropical phenomena.  相似文献   

6.
利用中国降水逐日站点观测资料以及HadISST海温资料,分析了1961-2010年东北地区70个观测站夏季降水的变化特征以及太平洋海温对东北夏季降水的可能影响。结果表明:东北夏季降水近50a来呈现下降趋势,具有多阶段性,在60年代以及80-90年代存在明显的突变;在1986-1985年以及1986-2010年2个阶段,热带外太平洋与热带太平洋春季和夏季海温都存在与东北夏季降水的相关关键区,两个阶段相关性显著不同甚至相反,是1961-2010年东北夏季降水与太平洋海温总体相关性较弱的原因。东北夏季降水与太平洋海温的相关性可能与海温冷暖背景有关系:在暖的海温背景下,东北降水与热带太平洋海温呈现显著的正相关;而对于热带外太平洋,暖的海温背景下,两者为负相关,冷的海温背景下,两者为正相关,尤其表现在春季,因此太平洋春季海温异常对于东北夏季降水预测有较好的指示意义。  相似文献   

7.
海水表面温度(SST)与渔业资源有着密切的关系,对SST的时空分布和变化的研究,是海洋渔业研究的基本内容之一。本文首先对SST数据在空间和时间上的变异分析方法进行了探讨,提出了SST时空相关阵的构建思想和方法,并在北太八年SST数据的基础上构建了以渔区为单位的时空相关阵,对该阵进行了空间插值检验,结果证明该方法的插值精度较高。  相似文献   

8.
重组人粒细胞-巨噬细胞集落刺激因子菌种稳定性研究   总被引:1,自引:0,他引:1  
 为了解含重组质粒的大肠杆菌菌种连续传代及发酵罐培养中质粒的遗传稳定性,将GM-CSF菌种在含氨苄青霉素的琼脂平皿上连续划线传代培养,以及在不含安苄青霉素的培养基中进行发酵罐培养和42℃诱导表达.结果显示pBV220GM-CSF工程菌在氨苄青霉素选择压力下连续传代10,25,50和100次后质粒稳定、不丢失,而在不含氨苄青霉素的培养基中进行发酵罐大规模培养42℃诱导表达时,质粒稳定性下降,质粒易丢失,其表达量随诱导时间而变化.  相似文献   

9.
近百年来长江洪水变化的初步分析   总被引:2,自引:0,他引:2  
采用水文时间系列的逐项分析法,统计分析了近百年来长江洪水变化的总体趋势与主要周期,发现近百年来长江洪水变化存在增大的总体趋势,并有40a,35a等主要周期变化。这与近百年气候的趋暖性变化及太阳活动的周期性强弱变化有关。  相似文献   

10.
气候变化背景下渤黄海海温时空特征分析   总被引:1,自引:0,他引:1       下载免费PDF全文
【目的】研究渤黄海海温时空变化特征及其与全球海温的关系。【方法】采用相关分析、小波分析等方法,对1985—2015年渤黄海海洋站的海温观测资料进行分析。【结果】渤海是中国内海,沿岸海温受陆地影响显著,变化幅度大,对气温响应快;黄海作为太平洋的边缘海,与外海水体交换通畅,水温变化幅度相对较小,水温变化与渤海相比具有一定的滞后性;各站海温变化周期特征不尽相同,但在2000年以后各站均有较为明显的8年周期;渤黄海海温与全球大部分海域一致,近30年呈现上升趋势,但上升速率与同纬度太平洋和大西洋相比较低,黄海海温上升速率高于渤海。【结论】渤黄海海温具有明显的月际、年际和周期变化特征,受海陆分布等因素影响渤黄海海温对气候变暖的响应低于同纬度太平洋和大西洋。  相似文献   

11.
The global sea surface temperature (SST) anomaly data from 1950 to 1996 were used to analyze spatial characters of interdecadal SST variations. A wavelet transform was made for the equatorial eastern Pacific SST anomaly time series. Results show that there are three remarkable timescale SST variations: 130-month interdecadal variation, 57-month interannual variation and 28-month quasi-2-a variation. Based on this result, an El Nino event was predicted in the early part of 1997.  相似文献   

12.
本研究对广西北部湾近岸海域2002-2021年发生的20次赤潮灾害进行综合分析,结果表明:近20年广西近岸海域赤潮平均每年发生1次,发生面积约为384 km2,持续时间为3.65 d,主要集中在春夏季,近10年(2012-2021年)相对前10年(2002-2011年)赤潮发生面积增加(18倍)。引发赤潮的生物种类共有10种,其中次数最多的是球形棕囊藻(Phaeocystis globosa),其次是夜光藻(Noctiluca scintillans)、水华微囊藻(Microcystis flos-aquae)和红海束毛藻(Trichodesmium erythraeum),但近10年不断有新的赤潮藻种出现。赤潮发生总数中,有毒或有害赤潮11次,分别为球形棕囊藻4次,夜光藻和水华微囊藻各3次,链状裸甲藻(Gymnodinium catenatum)1次。广西近岸海域赤潮发生的分布范围广,2008年以前主要发生在北海市涠洲岛海域,2008年以后钦州市三娘湾和三墩岛海域、北海市廉州湾及防城港市防城湾陆续开始发生赤潮。通过综合分析近20年北部湾近岸海域赤潮发生和分布的基...  相似文献   

13.
A Porites lutea core from Yongshu Reef of Nansha Islands covering 50 years growth history was analyzed for oxygen isotopic composition with monthly and seasonally resolution. The calibration of the δ 18O with the instrumental temperature indicated that the coral δ 18O is a good indicator for sea surface temperature (SST) and air temperature ( t ). It can be used to reconstruct the SST and air temperature of the Yongshu Reef sea area. In addition, the coral δ 18O provides signatures for the intensity of the East Asia monsoon and it is a record for the activities of El Niño events. With the calibrated SST and air temperature formulas, the most recent fifty years SST and air temperature were reconstructed based on the coral δ 18O, thus back up the understanding of the climate of Nansha Islands to 1950, far beyond the limit of the instrumental recording since September 1988. It was found that, in general, increasing 1℃ air temperature results in 0.24‰ decrease in skeletal δ 18O.  相似文献   

14.
黄、东海沿岸海表温度变化与厄尔尼诺的关系   总被引:1,自引:0,他引:1  
利用黄、东海沿岸8个长期水文观测站多年海表温度资料,分析黄、东海沿岸海表温度的季节和年际变化特征,重点分析在1982—1983年和1997—1998年两次厄尔尼诺年期间的异常变化,以及ENSO影响黄、东海沿岸海表温度的可能机制。结果表明,在厄尔尼诺发生年,夏季风较弱,鄂霍次克海高压加强,西太平洋副高位置偏南,强度偏强,江淮流域及长江中下游降水偏多,黄、东海沿岸海表温度偏低。黄、东海沿岸海表温度受到ENSO和PDO(太平洋年代际振荡)的影响和调制,在厄尔尼诺发生的前冬半年及当年,黄、东海沿岸海表温度偏低;在厄尔尼诺发生次年,黄、东海沿岸海表温度偏高。厄尔尼诺对黄、东海沿岸海表温度变化的影响通过海洋和大气2个通道,1982—1983年海表温度异常以负异常为主,1997—1998年海表温度异常以正异常为主;ENSO期间,北赤道流减弱,黑潮流量减少,海表温度降低。海表温度受局地气温影响显著,如果ENSO期间东亚气温升高,则黄、东海沿岸海表温度偏高。  相似文献   

15.
Indian Ocean temperature dipole and SSTA in the equatorial Pacific Ocean   总被引:6,自引:0,他引:6  
The observed sea surface temperature (SST) data of recent 100 years are analyzed and the existence of the Indian Ocean temperature dipole in the equatorial region is exposed further. It is very clear that the amplitude of the positive phase (higher SST in the west and lower SST in the east than normal) is larger than that of the negative phase (higher SST in the east and lower SST in the west). The dipole is stronger in September-November and weaker in January-April than in other months and it also appears obviously inter-annual and inter-decadal variations. Although the Indian Ocean dipole in the individual year seems to be independent of ENSO in the equatorial Pacific Ocean, in general, the Indian Ocean dipole has obviously negative correlation with the Pacific Ocean dipole (similar to the inverse phase of ENSO mode). The atmospheric zonal (Walker) circulation over the equator is fundamental to relate the two dipoles to each other.  相似文献   

16.
LU Riyu 《科学通报(英文版)》2005,50(18):2069-2073
The rainfall in North China during rainy season (July and August (JA)) exhibits a strong interannual variability. In this study, the atmospheric circulation and SST anomalies associated with the interannual variation of JA North China rainfall are examined. It is found that on the interannual timescale, the JA North China rainfall is associated with significant SST anomalies in the equatorial eastern Pacific, and the North China rainfall and SST anomaly in the equatorial eastern Pacific correspond to the similar variation of the upper-level westerly jet stream over East Asia. A possible mechanism is proposed for the influence of the SST anomalies in the equatorial eastern Pacific on the North China rainfall.  相似文献   

17.
Reconstruction and analysis of time series of ENSO for the last 500 years   总被引:3,自引:0,他引:3  
This paper reports the classification of ENSO into seven categories according to annual (March to February of next year) mean SST of Ni(n)o 3.4 and composite index (ΔI) for the period of 1861~2000. Categories +3, +2, and +1 denote very strong, strong and weak warm episodes (E), -3, -2, and -1 mean very strong, strong and weak cold episodes (A). Absolute SST anomalies are about 1.5 ℃, 1.0 ℃ and 0.5 ℃ respectively for the categories 3, 2, and 1 (or -3, -2, and -1). The normal years are expressed as category 0. Annual categories of ENSO are estimated on the basis of proxy data from AD 1501 to 1860. And a series of ENSO category is established for the period of 1501~2000 in conjunction with the observational data. Comparison of proxy data with observations for 1874~1973 indicates that about 80% of the El Ni(n)o years and La Ni(n)a years can be reconstructed from proxy data, and the reliability of the reconstruction is verified. Analysis of the power spectrum of the reconstructed ENSO series shows significant peaks at QBO, 3~4a (year), 5~6a, and 10a period, the former three are in accordance with the observations for the last 100 years or more. Studies on long term variability of ENSO indicates that ENSO frequency is relatively stationary during the last 500 years, including the Little Ice Age (LIA) (1550~1850) and Modern Warming Period (the 20th century). However, the frequency of E is a little higher in the 20th century and that of A is somewhat higher during the LIA.  相似文献   

18.
茅尾海富营养化程度及其对浮游植物生物量的影响   总被引:7,自引:0,他引:7       下载免费PDF全文
于2003~2010年每年的枯水季(1~3月)、丰水季(6~8月)和平水季(10~11月)对茅尾海每年3期共22次表层海水取样,调查无机氮、磷酸盐、化学需氧量及浮游植物叶绿素a的变化,用富营养化指数评价该海域的富营养化程度,并分析营养化程度对浮游植物生物量的影响.结果发现,茅尾海无机氮、磷酸盐和化学需氧量均显上升的趋势...  相似文献   

19.
According to systemically monitoring results of oxygen (hydrogen) isotope compositions of precipitation, soil waters, soil CO2, cave drip waters and their corresponding speleothems in Liangfeng Cave (LFC) in Guizhou Province, Southwest China, it is found that local precipitation is the main source of soil waters and drip waters, and that the amplitudes of those δ18O values of three waters (precipitation, soil water and drip water) decrease in turn in the observed year, which are 0‰ to -10‰, -2‰ to -9‰ and -6‰ to -8‰, respectively. Moreover, the δ18O values for three waters show a roughly simultaneous variation, namely, that those values are lighter in the rainy seasons, weightier in the dry seasons, and that the average δ18O value of drip waters is about 0.3‰ weightier than that of precipitation, which is modified by surface evaporation processes. We also find that oxygen isotope equilibrium is reached or neared in the formation processes of speleothems in LFC system, and that it is feasible to reconstruct paleotemperature and paleoprecipitation by using δ18O values of speleothems. However, it should be noted that surface evaporation would affect the oxygen isotope values in the study area.  相似文献   

20.
利用海表温度的遥感资料,分析了吕宋海峡及其周边海域海表温度的季节变化及其区域特征,并初步分析了其主要特征的形成原因.研究结果表明:冬季海表温度除受太阳辐射、东北季风的影响外,还受该区域海流、海陆分布的影响,因此温度场呈现出多个水舌结构;夏季海表温度空间分布较均匀,冬季的水舌结构基本消失;同时在台湾梅峡西岸以及吕宋岛东、西两侧海域分别出现上升流导致的低温区和大于30.0 C的高温区,后者主要受海面辐射、海流等的影响.绝大部分研究海域内的海表温度极大值出现在7月,但在吕宋岛以西海区、台湾海峡中北部海区海表温度极大值分别出现在5月和8月;相对而言,海表温度的极小值主要出现在1月,研究区域东北部124°~126°E海域推迟到2月.  相似文献   

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