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  1. Book ; Online: Expanded GHOST database, supplementary data to: Leduc, Guillaume; Schneider, Ralph R; Kim, Jung-Hyun; Lohmann, Gerrit (2010): Holocene and Eemian Sea surface temperature trends as revealed by alkenone and Mg/Ca paleothermometry. Quaternary Science Reviews, 29, 989-1004

    Leduc, Guillaume / Kim, Jung-Hyun / Lohmann, Gerrit / Schneider, Ralph R

    2010  

    Abstract: ... database (Kim, J.-H., Schneider R.R., 2004). The actualized GHOST database not only confirms the SST ...

    Abstract In this study we review a global set of alkenone- and foraminiferal Mg/Ca-derived sea surface temperatures (SST) records from the Holocene and compare them with a suite of published Eemian SST records based on the same approach. For the Holocene, the alkenone SST records belong to the actualized GHOST database (Kim, J.-H., Schneider R.R., 2004). The actualized GHOST database not only confirms the SST changes previously described but also documents the Holocene temperature evolution in new oceanic regions such as the Northwestern Atlantic, the eastern equatorial Pacific, and the Southern Ocean. A comparison of Holocene SST records stemming from the two commonly applied paleothermometry methods reveals contrasting - sometimes divergent - SST evolution, particularly at low latitudes where SST records are abundant enough to infer systematic discrepancies at a regional scale. Opposite SST trends at particular locations could be explained by out-of-phase trends in seasonal insolation during the Holocene. This hypothesis assumes that a strong contrast in the ecological responses of coccolithophores and planktonic foraminifera to winter and summer oceanographic conditions is the ultimate reason for seasonal differences in the origin of the temperature signal provided by these organisms. As a simple test for this hypothesis, Eemian SST records are considered because the Holocene and Eemian time periods experienced comparable changes in orbital configurations, but had a higher magnitude in insolation variance during the Eemian. For several regions, SST changes during both interglacials were of a similar sign, but with higher magnitudes during the Eemian as compared to the Holocene. This observation suggests that the ecological mechanism shaping SST trends during the Holocene was comparable during the penultimate interglacial period. Although this "ecology hypothesis" fails to explain all of the available results, we argue that any other mechanism would fail to satisfactorily explain the observed SST discrepancies among proxies.
    Language English
    Dates of publication 2010-9999
    Size Online-Ressource
    Publisher PANGAEA - Data Publisher for Earth & Environmental Science
    Publishing place Bremen/Bremerhaven
    Document type Book ; Online
    Note This dataset is supplement to doi:10.1016/j.quascirev.2010.01.004
    DOI 10.1594/PANGAEA.737370
    Database Library catalogue of the German National Library of Science and Technology (TIB), Hannover

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  2. Book ; Online: AMS radiocarbon dates and pollen analysis of ODP Hole 175-1078C, supplementary data to: Dupont, Lydie M; Behling, Hermann; Kim, Jung-Hyun (2008): Thirty thousand years of vegetation development and climate change in Angola (Ocean Drilling Program Site 1078). Climate of the Past, 4, 107-124

    Dupont, Lydie M / Behling, Hermann / Kim, Jung-Hyun

    2008  

    Abstract: ODP Site 1078 situated under the coast of Angola provides the first record of the vegetation history for Angola. The upper 11 m of the core covers the past 30 thousand years, which has been analysed palynologically in decadal to centennial resolution. ... ...

    Abstract ODP Site 1078 situated under the coast of Angola provides the first record of the vegetation history for Angola. The upper 11 m of the core covers the past 30 thousand years, which has been analysed palynologically in decadal to centennial resolution. Alkenone sea surface temperature estimates were analysed in centennial resolution. We studied sea surface temperatures and vegetation development during full glacial, deglacial, and interglacial conditions. During the glacial the vegetation in Angola was very open consisting of grass and heath lands, deserts and semi-deserts, which suggests a cool and dry climate. A change to warmer and more humid conditions is indicated by forest expansion starting in step with the earliest temperature rise in Antarctica, 22 thousand years ago. We infer that around the period of Heinrich Event 1, a northward excursion of the Angola Benguela Front and the Congo Air Boundary resulted in cool sea surface temperatures but rain forest remained present in the northern lowlands of Angola. Rain forest and dry forest area increase 15 thousand years ago. During the Holocene, dry forests and Miombo woodlands expanded. Also in Angola globally recognised climate changes at 8 thousand and 4 thousand years ago had an impact on the vegetation. During the past 2 thousand years, savannah vegetation became dominant.
    Language English
    Dates of publication 2008-9999
    Size Online-Ressource
    Publisher PANGAEA - Data Publisher for Earth & Environmental Science
    Publishing place Bremen/Bremerhaven
    Document type Book ; Online
    Note This dataset is supplement to doi:10.5194/cp-4-107-2008
    DOI 10.1594/PANGAEA.726887
    Database Library catalogue of the German National Library of Science and Technology (TIB), Hannover

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  3. Book ; Online: TEXL86-based oceanic temperatures in sediment core MD03-2601, supplementary data to: Kim, Jung-Hyun; Crosta, Xavier; Willmott, Verónica; Renssen, Hans; Bonnin, Jerome; Helmke, Peer; Schouten, Stefan; Sinninghe Damsté, Jaap S (2012): Holocene subsurface temperature variability in the eastern Antarctic continental margin. Geophysical Research Letters, 39, L06705

    Kim, Jung-Hyun / Bonnin, Jerome / Crosta, Xavier / Helmke, Peer / Renssen, Hans / Schouten, Stefan / Sinninghe Damsté, Jaap S / Willmott, Verónica

    2012  

    Abstract: We reconstructed subsurface (~45-200 m water depth) temperature variability in the eastern Antarctic continental margin during the late Holocene, using an archaeal lipid-based temperature proxy (TEX86L). Our results reveal that subsurface temperature ... ...

    Abstract We reconstructed subsurface (~45-200 m water depth) temperature variability in the eastern Antarctic continental margin during the late Holocene, using an archaeal lipid-based temperature proxy (TEX86L). Our results reveal that subsurface temperature changes were probably positively coupled to the variability of warmer, nutrient-rich Modified Circumpolar Deep Water (MCDW, deep water of the Antarctic circumpolar current) intrusion onto the continental shelf. The TEX86L record, in combination with previously published climatic records, indicates that this coupling was probably related to the thermohaline circulation, seasonal variability in sea ice extent, sea temperature, and wind associated with high frequency climate dynamics at low-latitudes such as internal El Niño Southern Oscillation (ENSO). This in turn suggests a linkage between centennial ENSO-like variability at low-latitudes and intrusion variability of MCDW into the eastern Antarctic continental shelf, which might have further impact on ice sheet evolution.
    Language English
    Dates of publication 2012-9999
    Size Online-Ressource
    Publisher PANGAEA - Data Publisher for Earth & Environmental Science
    Publishing place Bremen/Bremerhaven
    Document type Book ; Online
    Note This dataset is supplement to doi:10.1029/2012GL051157
    DOI 10.1594/PANGAEA.788511
    Database Library catalogue of the German National Library of Science and Technology (TIB), Hannover

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  4. Book ; Online: Pollen distribution of sediment core MD96-2048 from the Western Indian Ocean, supplementary data to: Dupont, Lydie M; Caley, Thibaut; Kim, Jung-Hyun; Castañeda, Isla S; Malaizé, Bruno; Giraudeau, Jaques (2011): Glacial-interglacial vegetation dynamics in South Eastern Africa coupled to sea surface temperature variations in the Western Indian Ocean. Climate of the Past, 7(4), 1209-1224

    Dupont, Lydie M / Caley, Thibaut / Castañeda, Isla S / Giraudeau, Jaques / Kim, Jung-Hyun / Malaizé, Bruno

    2011  

    Abstract: Glacial-interglacial fluctuations in the vegetation of South Africa might elucidate the climate system at the edge of the tropics between the Indian and Atlantic Oceans. However, vegetation records covering a full glacial cycle have only been published ... ...

    Abstract Glacial-interglacial fluctuations in the vegetation of South Africa might elucidate the climate system at the edge of the tropics between the Indian and Atlantic Oceans. However, vegetation records covering a full glacial cycle have only been published from the eastern South Atlantic. We present a pollen record of the marine core MD96-2048 retrieved by the Marion Dufresne from the Indian Ocean ~120 km south of the Limpopo River mouth. The sedimentation at the site is slow and continuous. The upper 6 m (spanning the past 342 Ka) have been analysed for pollen and spores at millennial resolution. The terrestrial pollen assemblages indicate that during interglacials, the vegetation of eastern South Africa and southern Mozambique largely consisted of evergreen and deciduous forests. During glacials open mountainous scrubland dominated. Montane forest with Podocarpus extended during humid periods was favoured by strong local insolation. Correlation with the sea surface temperature record of the same core indicates that the extension of mountainous scrubland primarily depends on sea surface temperatures of the Agulhas Current. Our record corroborates terrestrial evidence of the extension of open mountainous scrubland (including fynbos-like species of the high-altitude Grassland biome) for the last glacial as well as for other glacial periods of the past 300 Ka.
    Language English
    Dates of publication 2011-9999
    Size Online-Ressource
    Publisher PANGAEA - Data Publisher for Earth & Environmental Science
    Publishing place Bremen/Bremerhaven
    Document type Book ; Online
    Note This dataset is supplement to doi:10.5194/cp-7-1209-2011
    DOI 10.1594/PANGAEA.771285
    Database Library catalogue of the German National Library of Science and Technology (TIB), Hannover

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  5. Book ; Online: Geochemistry and paleontology of sediment core GeoB3359-3, supplementary data to: Romero, Oscar E; Kim, Jung-Hyun; Hebbeln, Dierk (2006): Paleoproductivity evolution off central Chile from the Last Glacial Maximum to the Early Holocene. Quaternary Research, 65(3), 519-525

    Romero, Oscar E / Hebbeln, Dierk / Kim, Jung-Hyun

    2006  

    Abstract: A geochemical and paleontological reconstruction of paleoproductivity, upwelling intensity and sea surface temperature (SST) off central Chile at 35?S (GeoB3359-3) reveals marked changes from the Last Glacial Maximum (LGM) through the Early Holocene. ... ...

    Abstract A geochemical and paleontological reconstruction of paleoproductivity, upwelling intensity and sea surface temperature (SST) off central Chile at 35?S (GeoB3359-3) reveals marked changes from the Last Glacial Maximum (LGM) through the Early Holocene. Surface-water productivity was determined by the interaction between the atmospheric (the Southern Westerlies) and oceanographic (the Antarctic Circumpolar Current, ACC) systems from the LGM through early Termination I (TI). The northward shift of the climate zones during the LGM brought the ACC, as the main macronutrient source, closer to the GeoB3359-3, SST lowered, and surface water productivity and accumulation rates of biogenic components enhanced. With the poleward return of the Southern Westerlies and the ACC, the subtropical high-pressure system became the dominant atmospheric component southward till 35?S during the late TI and Early Holocene and caused surface water productivity to increase through enhanced upwelling.
    Language English
    Dates of publication 2006-9999
    Size Online-Ressource
    Publisher PANGAEA - Data Publisher for Earth & Environmental Science
    Publishing place Bremen/Bremerhaven
    Document type Book ; Online
    Note This dataset is supplement to doi:10.1016/j.yqres.2005.07.003
    DOI 10.1594/PANGAEA.738190
    Database Library catalogue of the German National Library of Science and Technology (TIB), Hannover

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  6. Book ; Online: Geochemical and palynological results of IODP Hole 302-M0004A from Lomonosov Ridge, Arctic <BR>Ocean, supplementary data to: Sluijs, Appy; Schouten, Stefan; Donders, Timme H; Schoon, Petra L; R?hl, Ursula; Reichart, Gerd-Jan; Sangiorgi, Francesca; Kim, Jung-Hyun; Sinninghe Damst?, Jaap S; Brinkhuis, Henk (2009): Warm and wet conditions in the Arctic region during Eocene Thermal Maximum 2. Nature Geosciences, 2, 777-780

    Sluijs, Appy / Brinkhuis, Henk / Donders, Timme H / Kim, Jung-Hyun / R?hl, Ursula / Reichart, Gerd-Jan / Sangiorgi, Francesca / Schoon, Petra L / Schouten, Stefan / Sinninghe Damst?, Jaap S

    2010  

    Abstract: Several episodes of abrupt and transient warming, each lasting between 50,000 and 200,000 years, punctuated the long-term warming during the Late Palaeocene and Early Eocene (58 to 51 Myr ago) epochs**1,2. These hyperthermal events, such as the Eocene ... ...

    Abstract Several episodes of abrupt and transient warming, each lasting between 50,000 and 200,000 years, punctuated the long-term warming during the Late Palaeocene and Early Eocene (58 to 51 Myr ago) epochs**1,2. These hyperthermal events, such as the Eocene Thermal Maximum 2 (ETM2) that took place about 53.5 Myr ago**2, are associated with rapid increases in atmospheric CO2 content. However, the impacts of most events are documented only locally**3,4. Here we show, on the basis of estimates from the TEX86' proxy, that sea surface temperatures rose by 3-5 ?C in the Arctic Ocean during the ETM2. Dinoflagellate fossils demonstrate a concomitant freshening and eutrophication of surface waters, which resulted in euxinia in the photic zone. The presence of palm pollen implies**5 that coldest month mean temperatures over the Arctic land masses were no less than 8 ?C, in contradiction of model simulations that suggest hyperthermal winter temperatures were below freezing**6. In light of our reconstructed temperature and hydrologic trends, we conclude that the temperature and hydrographic responses to abruptly increased atmospheric CO2 concentrations were similar for the ETM2 and the better-described Palaeocene-Eocene Thermal Maximum**7,8, 55.5 Myr ago.
    Language English
    Dates of publication 2010-9999
    Size Online-Ressource
    Publisher PANGAEA - Data Publisher for Earth & Environmental Science
    Publishing place Bremen/Bremerhaven
    Document type Book ; Online
    Note This dataset is supplement to doi:10.1038/NGEO668
    DOI 10.1594/PANGAEA.735745
    Database Library catalogue of the German National Library of Science and Technology (TIB), Hannover

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  7. Book ; Online: Sedimentology and gas hydrates of IODP Expedition 311 samples, supplementary data to: Torres, Marta E; Tréhu, Anne M; Cespedes, N; Kastner, Miriam; Wortmann, Ulrich G; Kim, Jung-Hyun; Long, Philip E; Malinverno, Alberto; Pohlman, John W; Riedel, Michael; Collett, Tim S (2008): Methane hydrate formation in turbidite sediments of northern Cascadia, IODP Expedition 311. Earth and Planetary Science Letters, 271(1-4), 170-180

    Torres, Marta E / Cespedes, N / Kastner, Miriam / Kim, Jung-Hyun / Long, Philip E / Malinverno, Alberto / Pohlman, John W / Tréhu, Anne M / Wortmann, Ulrich G / al., et

    2008  

    Abstract: Expedition 311 of the Integrated Ocean Drilling Program (IODP) to northern Cascadia recovered gas-hydrate bearing sediments along a SW-NE transect from the first ridge of the accretionary margin to the eastward limit of gas-hydrate stability. In this ... ...

    Abstract Expedition 311 of the Integrated Ocean Drilling Program (IODP) to northern Cascadia recovered gas-hydrate bearing sediments along a SW-NE transect from the first ridge of the accretionary margin to the eastward limit of gas-hydrate stability. In this study we contrast the gas gas-hydrate distribution from two sites drilled ~ 8 km apart in different tectonic settings. At Site U1325, drilled on a depositional basin with nearly horizontal sedimentary sequences, the gas-hydrate distribution shows a trend of increasing saturation toward the base of gas-hydrate stability, consistent with several model simulations in the literature. Site U1326 was drilled on an uplifted ridge characterized by faulting, which has likely experienced some mass wasting events. Here the gas hydrate does not show a clear depth-distribution trend, the highest gas-hydrate saturation occurs well within the gas-hydrate stability zone at the shallow depth of ~ 49 mbsf. Sediments at both sites are characterized by abundant coarse-grained (sand) layers up to 23 cm in thickness, and are interspaced within fine-grained (clay and silty clay) detrital sediments. The gas-hydrate distribution is punctuated by localized depth intervals of high gas-hydrate saturation, which preferentially occur in the coarse-grained horizons and occupy up to 60% of the pore space at Site U1325 and > 80% at Site U1326. Detailed analyses of contiguous samples of different lithologies show that when enough methane is present, about 90% of the variance in gas-hydrate saturation can be explained by the sand (> 63 æm) content of the sediments. The variability in gas-hydrate occupancy of sandy horizons at Site U1326 reflects an insufficient methane supply to the sediment section between 190 and 245 mbsf.
    Language English
    Dates of publication 2008-9999
    Size Online-Ressource
    Publisher PANGAEA - Data Publisher for Earth & Environmental Science
    Publishing place Bremen/Bremerhaven
    Document type Book ; Online
    Note This dataset is supplement to doi:10.1016/j.epsl.2008.03.061
    DOI 10.1594/PANGAEA.716589
    Database Library catalogue of the German National Library of Science and Technology (TIB), Hannover

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  8. Book ; Online: Pollen analysis of sediment cores from the mouth of the river Congo to Walvis Bay and Lüderitz, supplementary data to: Dupont, Lydie M; Behling, Hermann; Jahns, Susanne; Marret, Fabienne; Kim, Jung-Hyun (2007): Variability in glacial and Holocene marine pollen records offshore from west southern Africa. Vegetation History and Archaeobotany, 16, 87-100

    Dupont, Lydie M / Behling, Hermann / Jahns, Susanne / Kim, Jung-Hyun / Marret, Fabienne

    2007  

    Abstract: The distribution of pollen in marine sediments is used to record vegetation changes over the past 30,000 years on the adjacent continent. A transect of marine pollen sequences from the mouth of the river Congo (~5°S) to Walvis Bay and Lüderitz (~25°S) ... ...

    Abstract The distribution of pollen in marine sediments is used to record vegetation changes over the past 30,000 years on the adjacent continent. A transect of marine pollen sequences from the mouth of the river Congo (~5°S) to Walvis Bay and Lüderitz (~25°S) shows vegetation changes in Congo, Angola and Namibia from the last glacial period into the Holocene. The comparison of pollen records from different latitudes provides information about the latitudinal shift of open forest and savannahs (Poaceae pollen), the extension of lowland forest (rain forest pollen) and Afromontane forest (Podocarpus pollen), and the position of the desert fringe (pollen of Caryophyllaceae, Chenopodiaceae and Amaranthaceae). High Cyperaceae pollen percentages in sediments from the last glacial period off the mouth of the river Congo suggest the presence of open swamps rather than savannah vegetation in the Congo Basin. Pollen from Restionaceae in combination with Stoebe-type pollen (probably from Elytropappus) indicates a possible northwards extension of winter rain vegetation during the last glacial period. The record of Rhizophora (mangrove) pollen is linked to erosion of the continental shelf and sea-level rise. Pollen influx is highest off river mouths (10-2000 grains year**-1 cm**-2), close to the coast (300-6000 grains year**-1 cm**-2), but is an order of magnitude lower at sites situated far from the continent (<10 grains year**-1 cm**-2).
    Language English
    Dates of publication 2007-9999
    Size Online-Ressource
    Publisher PANGAEA - Data Publisher for Earth & Environmental Science
    Publishing place Bremen/Bremerhaven
    Document type Book ; Online
    Note This dataset is supplement to doi:10.1007/s00334-006-0080-8
    DOI 10.1594/PANGAEA.726889
    Database Library catalogue of the German National Library of Science and Technology (TIB), Hannover

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  9. Book ; Online: Sea-surface temperature reconstruction of sediments from the North Pacific and North Atlantic, supplementary data to: Kim, Jung-Hyun; Rimbu, Norel; Lorenz, Stefan J; Lohmann, Gerrit; Schneider, Ralph R; Nam, Seung-Il; Schouten, Stefan; Sirocko, Frank; R?hlemann, Carsten (2004): North Pacific and North Atlantic sea-surface temperature variability during the Holocene. Quaternary Science Reviews, 23(20-22), 2141-2154

    Kim, Jung-Hyun / Lohmann, Gerrit / Lorenz, Stefan J / Nam, Seung-Il / R?hlemann, Carsten / Rimbu, Norel / Schneider, Ralph R / Schouten, Stefan

    2004  

    Abstract: Holocene climate variability is investigated in the North Pacific and North Atlantic realms, using alkenone-derived sea-surface temperature (SST) records as well as a millennial scale simulation with a coupled atmosphere-ocean general circulation model ( ... ...

    Abstract Holocene climate variability is investigated in the North Pacific and North Atlantic realms, using alkenone-derived sea-surface temperature (SST) records as well as a millennial scale simulation with a coupled atmosphere-ocean general circulation model (AOGCM). The alkenone SST data indicate a temperature increase over almost the entire North Pacific from 7?cal?kyr BP to the present. A dipole pattern with a continuous cooling in the northeastern Atlantic and a warming in the eastern Mediterranean Sea and the northern Red Sea is detected in the North Atlantic realm. Similarly, SST variations are opposite in sign between the northeastern Pacific and the northeastern Atlantic. A 2300 year long AOGCM climate simulation reveals a similar SST seesaw between the northeastern Pacific and the northeastern Atlantic on centennial time scales. Our analysis of the alkenone SST data and the model results suggests fundamental inter-oceanic teleconnections during the Holocene.
    Language English
    Dates of publication 2004-9999
    Size Online-Ressource
    Publisher PANGAEA - Data Publisher for Earth & Environmental Science
    Publishing place Bremen/Bremerhaven
    Document type Book ; Online
    Note This dataset is supplement to doi:10.1016/j.quascirev.2004.08.010
    DOI 10.1594/PANGAEA.738435
    Database Library catalogue of the German National Library of Science and Technology (TIB), Hannover

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  10. Book ; Online: Sea-surface tempertaure reconstruction of sediment cores from the Southeast Pacific, supplementary data to: Kim, Jung-Hyun; Schneider, Ralph R; Hebbeln, Dierk; M?ller, Peter J; Wefer, Gerold (2002): Last deglacial sea-surface temperature evolution in the Southeast Pacific compared to climate changes on the Sourth American continent. Quaternary Science Reviews, 21(18-19), 2085-2097

    Kim, Jung-Hyun / Hebbeln, Dierk / M?ller, Peter J / Schneider, Ralph R / Wefer, Gerold

    2002  

    Abstract: ... in the Peru-Chile current off mid-latitude Chile.

    REFERENCE:
    Kim, Jung-Hyun (2001): Reconstruction ...

    Abstract Applying the alkenone method, we estimated sea-surface temperatures (SSTs) for the past 33?kyr in two marine sediment cores recovered from the continental slope off mid-latitude Chile. The SST record shows an increase of 6.7?C from the last ice age (LIA) to the Holocene climatic optimum, while the temperature contrast between LIA and modern temperatures is only about 3.4?C. The timing and magnitude of the last deglacial warming in the ocean correspond to those observed in South American continental records. According to our SST record, the existence of a Younger Dryas equivalent cooling in the Southeast Pacific is much more uncertain than for the continental climate changes. A warming step of about 2.5?C observed between 8 and 7.5?cal?kyr?BP may have been linked to the early to mid-Holocene climatic transition (8.2-7.8?cal?kyr?BP), also described from equatorial Africa and Antarctica. In principal, variations in the latitudinal position of the Southern Pacific Westerlies are considered to be responsible for SST changes in the Peru-Chile current off mid-latitude Chile.

    REFERENCE:
    Kim, Jung-Hyun (2001): Reconstruction of past sea-surface temperatures in the eastern south atlantic and the eastern south pacific across termination I based on the alkenone method. Berichte aus dem Fachbereich Geowissenschaften der Universit?t Bremen, 180, 114 pp
    Language English
    Dates of publication 2002-9999
    Size Online-Ressource
    Publisher PANGAEA - Data Publisher for Earth & Environmental Science
    Publishing place Bremen/Bremerhaven
    Document type Book ; Online
    Note This dataset is cited by urn:urn:nbn:de:gbv:46-ep000103081 ; This dataset is supplement to doi:10.1016/S0277-3791(02)00012-4
    DOI 10.1594/PANGAEA.735767
    Database Library catalogue of the German National Library of Science and Technology (TIB), Hannover

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