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Relations between sedimentary sequence and paleoclimatic changes during last 200 ka in the southern South China Sea
Muhong Chen,Xia Tu,Fan Zheng,Wen Yan,Xianzan Tang,Jun Lu,Baogui Wang,Miao’an Lu
Chinese Science Bulletin , 2000, DOI: 10.1007/BF03182915
Abstract: Core NS-93-5 was taken from the mild slope terrace of the southern South China Sea (SCS), which has preserved the steadiness depositional record of the normal marine environment since late Quaternary. Sedimentary sequence and oxygen isotopic stratigraphy of high resolution in the near 200 ka of the southern SCS has been established. By the comparative analysis with GISP2’s ice core, the depositional record of D/O’s events 1–21 and Heinrich’s events H1-H6 in the southern SCS that reflected the quick climate change in short time scale since the last interglacial stage is revealed, which indicates that in the last 200 ka in the southern SCS and the Arctic area there was tele-connection of paleoclimate and the instability of the Western Pacific Warm Pool. This note shows that the sedimentary layers order of this sea area classified by color identification and by oxygen isotope stratum has the very good corresponding relation. The color feature of sediment changes along with the climate and the former arranges a stagnant time of 1–1.5 ka generally. It was suggested that the paleoclimatic changes resulted in the rise and fall of sea level, the open and close of strait thoroughfare and the upwelling activity, which causes the changes of the oxidation-reduction condition of deep water along with the dynamic environment in this sea area, thus producing the different sediment features of sea bed. In addition, a volcanic ash layer, about 17 cm thick, has been found in the transition of oxygen isotope 4/5 stage, which is related with the Toba’s volcanic eruption.
A 250 ka oxygen isotope record from diatoms at Lake El'gygytgyn, far east Russian Arctic
B. Chapligin, H. Meyer, G. E. A. Swann, C. Meyer-Jacob,H.-W. Hubberten
Climate of the Past (CP) & Discussions (CPD) , 2012,
Abstract: In 2003 sediment core Lz1024 was drilled at Lake El'gygytgyn, far east Russian Arctic, in an area of the Northern Hemisphere which has not been glaciated for the last 3.6 Ma. Biogenic silica was used for analysing the oxygen isotope composition (δ18Odiatom) in the upper 13 m long section dating back about 250 ka with samples dominated by one taxa in the <10 μm fraction (Cyclotella ocellata). Downcore variations in δ18O values show that glacial-interglacial cycles are present throughout the core and δ18Odiatom-values are mainly controlled by δ18Oprecipitation. Changes reflect the Holocene Thermal Maximum, the Last Glacial Maximum (LGM) and the interglacial periods corresponding to MIS 5.5 and MIS 7 with a peak-to-peak amplitude between LGM and MIS 5.5 of Δ18O = 5.3‰. This corresponds to a mean annual air temperature difference of about 9 °C. Our record is the first continuous δ18Odiatom record from an Arctic lake sediment core directly responding to precipitation and dating back more than 250 ka and correlates well with the stacked marine δ18O LR04 (r = 0.58) and δD EPICA Dome-C record (r = 0.69). With δ18O results indicating strong links to both marine and ice-core records, records from Lake El'gygytgyn can be used to further investigate the sensitivity of the Arctic climate to both past and future global climatic changes.
A 250 ka oxygen isotope record from diatoms at Lake El'gygytgyn, far east Russian Arctic  [PDF]
B. Chapligin,H. Meyer,G. E. A. Swann,C. Meyer-Jacob
Climate of the Past Discussions , 2012, DOI: 10.5194/cpd-8-1169-2012
Abstract: In 2003 sediment core Lz1024 was drilled at Lake El'gygytgyn, far east Russian Arctic, in an area of the Northern Hemisphere which has not been glaciated for the last 3.6 Ma. Biogenic silica was used for analysing the oxygen isotope composition (δ18Odiatom) in the upper 13 m long section dating back about 250 ka with samples dominated by one taxa in the <10 μm fraction (Cyclotella ocellata). Downcore variations in δ18O values show that glacial-interglacial cycles are present throughout the core and δ18Odiatom values are mainly controlled by δ18Oprecipitation. Changes reflect the Holocene Thermal Maximum, the Last Glacial Maximum and the interglacial periods corresponding to MIS 5e and MIS 7 with a peak-to-peak amplitude of δ18O = 5.3 ‰. Our record is the first continuous δ18Odiatom record from an Arctic lake sediment core directly responding to precipitation and dating back more than 250 ka and correlates well with the stacked marine δ18O LR04 (r = 0.58) and δD EPICA Dome-C record (r = 0.69). With δ18O results indicating strong links to both marine and ice-core records, records from Lake El'gygytgyn can be used to further investigate the sensitivity of the Arctic climate to both past and future global climatic changes.
Palaeoenvironmental changes from pollen record in deep sea core PC-1 from northern Okinawa Trough, East China Sea during the past 24 ka
HongYan Xu,FengMing Chang,YunLi Luo,XiangJun Sun
Chinese Science Bulletin , 2009, DOI: 10.1007/s11434-009-0227-y
Abstract: A pollen record of core PC-1 from the northern Okinawa Trough, East China Sea (ECS), provides information on vegetation and climate changes since 24 cal. kaBP. A total of 103 samples were palynologically analyzed at 8 cm intervals with a time resolution of 230 a. Four pollen zones are recognized: zone I (812–715 cm, 24.2–21.1 cal. kaBP), zone II (715–451 cm, 21.1–15.2 cal. kaBP), zone III (451–251 cm, 15.2–10.8 cal. kaBP), zone IV (251–0 cm, 10.8–0.3 cal. kaBP), corresponding to Late MIS 3, Last Glacial Maximum (LGM), deglaciation and Holocene, respectively. The LGM is characterized by the dominance of herbs, mainly Artemisia, and high pollen influx, implying an open vegetation on the exposed continental shelf and a cool and dry climate. The deglaciation is a climate warming stage with Pinus percentage increased and Artemisia percentage decreased and a rapid sea-level rise. The Holocene is characterized by predominance of tree pollen with rapid increase in Castanea-Castanopsis indicating the development of mixed evergreen and deciduous broad-leaved forest and a warm, humid climate. Low pollen influx during the Holocene probably implies submergence of the continental shelf and retreat of the pollen source area. The vegetation indicated by pollen assemblage found in this upper zone is consistent with the present vegetation found in Kyushu, Japan. Originating from the humid mountain area of North Luzon of the Philippines, Tasmania and New Zealand, Phyllocladus with sporadic occurrence throughout PC-1 core probably suggests the influence of Palaeo-Kuroshio Current or intense summer monsoon. The observed changes in Pinus and Herbs percentage indicate fluctuations of the sea level, and high Pinus percentage corresponds to high sea level. Spectrum analysis of the pollen percentage record reveals many millennial-scale periodicities, such as periodicities of 6.8, 3.8, 2.2, 1.6 ka.
A continuous 200-ka palaeoclimatic record from stalagmite in Tangshan Cave, Nanjing
Yongjin Wang,Qi Chen,Zechun Liu,Ye Chen,Chunling Zhou,Conglun Lu
Chinese Science Bulletin , 1998, DOI: 10.1007/BF02898919
Abstract: An oxygen isotope temperature record from 381 to 166 kaB. P. (230Th/234U dating and tuned ages) has been obtained by combining data on the isotopic composition of calcites with that of fluid inclusions trapped in a stalagmite from a limestone cave in which a fossil cranium deposited. Several laminae in microsequence of the stalagmite represent climatic events or shifts. The Nanjing man fossil was older than 381 kaB. P.
A continuous 200-ka palaeoclimatic record from stalagmite in Tangshan Cave, Nanjing

Yongjin Wang,Qi Chen,Zechun Liu,Ye Chen,Chunling Zhou,Conglun Lu,

科学通报(英文版) , 1998,
Abstract: An oxygen isotope temperature record from 381 to 166 kaB. P. (230Th/234U dating and tuned ages) has been obtained by combining data on the isotopic composition of calcites with that of fluid inclusions trapped in a stalagmite from a limestone cave in which a fossil cranium deposited. Several laminae in microsequence of the stalagmite represent climatic events or shifts. The Nanjing man fossil was older than 381 kaB. P.
Strong summer monsoon during the cool MIS-13
Q. Z. Yin,Z. T. Guo
Climate of the Past (CP) & Discussions (CPD) , 2008,
Abstract: The δ18O record in deep-sea sediments show a significant reduced amplitude of the ice volume variations before Marine Isotope Stage 11, about 400 ka ago, with less warm interglacials and less cold glacials. The deuterium temperature and the greenhouse gases records in the Antarctic ice cores show the same feature. As the reduction in the amplitude of climate and greenhouse gases concentration variations before 400 ka BP is present in both deep-sea and ice cores, it is tempting to conclude that this is a worldwide phenomenon. This is not necessarily true, at least as far as some of the records, in particular of China and Europe, are concerned. The loess in northern China, the sedimentary core in the eastern Tibetan Plateau and the palaeosols in southern China all record an unusually warm and wet climate during Marine Isotope Stage 13, indicating an extremely strong East Asian summer monsoon. The pollen record from Europe shows that the climatic conditions during the interglacials previous to Marine Isotope Stage 11 are at least as warm as the younger interglacials. During Marine Isotope Stage 13, unusually strong African and Indian monsoon are recorded in the sediments of the equatorial Indian Ocean and of the Mediterranean Sea. Other extreme climate events are also recorded in sediment cores of the equatorial Atlantic, the Pacific, the subtropical South Atlantic Ocean and in the Lake Baikal of Siberia.
The marine sedimentary nitrogen isotope record  [PDF]
J. E. Tesdal,E. D. Galbraith,M. Kienast
Biogeosciences Discussions , 2012, DOI: 10.5194/bgd-9-4067-2012
Abstract: A global database of nitrogen isotope data from marine sediments is presented, including both seafloor and sub-seafloor sediment samples. The data synthesis reveals regionally and globally consistent patterns and trends, with good agreement between neighbouring seafloor sites. The spatial coverage of seafloor δ15N data is heterogenous, with excellent coverage in the eastern tropical Pacific, South China Sea and Arabian Sea, while large regions of the globe remain unsampled. The sub-seafloor δ15N records are mostly from the late Pleistocene, with >90 coeval records during the last ~10 kiloyears (kyr), before which the number of records at any time decreases, with <10 coeval records at any time prior to 300 kyr. There is a good correlation between seafloor and shallow-subseafloor δ15N measurements within a 100 km radius, which suggest a reliable translation of sediments into the buried sediment record. We suggest that regional discrepancies between seafloor and late Holocene subseafloor δ15N indicate nitrogen cycle changes during the late Holocene period, rather than systematic diagenetic changes.
Correlation of Greenland ice-core isotope profiles and the terrestrial record of the Alpine Rhine glacier for the period 32–15 ka  [PDF]
M. G. G. De Jong,L. W. S. de Graaff,A. C. Seijmonsbergen,A. R. B?hm
Climate of the Past Discussions , 2011, DOI: 10.5194/cpd-7-4335-2011
Abstract: We present a newly extended stratigraphic subdivision of the Greenland NGRIP, GRIP and GISP2 ice cores for the period 32–15 ka. Our classification emphasizes the multiscale nature of the climatic oscillations. Spectral trend analysis of isotopic data supports this interpretation. We compare this time series with the stratigraphy of the last major Pleistocene (Weichselian, Würmian) glaciation in the area of the Rhine glacier (Germany and Austria) as chronicled by a detailed inventory of landforms and deposits, dated in part with 14C analyses, and their interpretation in terms of climate change. Both time series show a major climatic oscillation, consisting of a colder period (glaciation) followed by a warmer period (deglaciation). The available dates allow the time of change, at 23.4 ka, to be correlated between the two. Pattern analysis clearly indicates that higher-order oscillations were superimposed on the major oscillation in both areas, emphasizing the multiscale nature of the underlying pattern of climate change. The correlation between the two areas is sufficiently good to propose that the pattern of climate change was synchronous (within the available time resolution) between Greenland and the Rhine glacier area. Comparison of our results with other high resolution climate proxies is expected to further improve the understanding of the climate changes during the Late Weichselian.
Changes in sea surface temperature in western South China Sea over the past 450 ka
Li Li,Hui Wang,JianRu Li,MeiXun Zhao,PinXian Wang
Chinese Science Bulletin , 2009, DOI: 10.1007/s11434-009-0083-9
Abstract: 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 U 37 k′ -SST results revealed similar glacial-interglacial cycles as the δ18O profile of planktonic foraminifera, with SST variability of 23–25.5°C for glacial and 25–28°C for interglacial periods. The highest SST (28.4°C) was recorded at MIS5.5 and lowest SST (22.6°C) during MIS2. The SST record preceded the planktonic foraminiferal δ18O 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.
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