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Speleology in Kazakhstan

Shakalov on 04 Jul, 2018
Hello everyone!   I pleased to invite you to the official site of Central Asian Karstic-Speleological commission ("Kaspeko")   There, we regularly publish reports about our expeditions, articles and reports on speleotopics, lecture course for instructors, photos etc. ...

Speleology in Kazakhstan

Shakalov on 04 Jul, 2018
Hello everyone!   I pleased to invite you to the official site of Central Asian Karstic-Speleological commission ("Kaspeko")   There, we regularly publish reports about our expeditions, articles and reports on speleotopics, lecture course for instructors, photos etc. ...

Speleology in Kazakhstan

Shakalov on 11 Jul, 2012
Hello everyone!   I pleased to invite you to the official site of Central Asian Karstic-Speleological commission ("Kaspeko")   There, we regularly publish reports about our expeditions, articles and reports on speleotopics, lecture course for instructors, photos etc. ...

New publications on hypogene speleogenesis

Klimchouk on 26 Mar, 2012
Dear Colleagues, This is to draw your attention to several recent publications added to KarstBase, relevant to hypogenic karst/speleogenesis: Corrosion of limestone tablets in sulfidic ground-water: measurements and speleogenetic implications Galdenzi,

The deepest terrestrial animal

Klimchouk on 23 Feb, 2012
A recent publication of Spanish researchers describes the biology of Krubera Cave, including the deepest terrestrial animal ever found: Jordana, Rafael; Baquero, Enrique; Reboleira, Sofía and Sendra, Alberto. ...

Caves - landscapes without light

akop on 05 Feb, 2012
Exhibition dedicated to caves is taking place in the Vienna Natural History Museum   The exhibition at the Natural History Museum presents the surprising variety of caves and cave formations such as stalactites and various crystals. ...

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That bathyphreatic zone is see bathyphreatic, ground water, phreas.?

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Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
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Mushroom Speleothems: Stromatolites That Formed in the Absence of Phototrophs, Bontognali, Tomaso R.R.; D’Angeli Ilenia M.; Tisato, Nicola; Vasconcelos, Crisogono; Bernasconi, Stefano M.; Gonzales, Esteban R. G.; De Waele, Jo
Calculating flux to predict future cave radon concentrations, Rowberry, Matt; Marti, Xavi; Frontera, Carlos; Van De Wiel, Marco; Briestensky, Milos
Microbial mediation of complex subterranean mineral structures, Tirato, Nicola; Torriano, Stefano F.F;, Monteux, Sylvain; Sauro, Francesco; De Waele, Jo; Lavagna, Maria Luisa; D’Angeli, Ilenia Maria; Chailloux, Daniel; Renda, Michel; Eglinton, Timothy I.; Bontognali, Tomaso Renzo Rezio
Evidence of a plate-wide tectonic pressure pulse provided by extensometric monitoring in the Balkan Mountains (Bulgaria), Briestensky, Milos; Rowberry, Matt; Stemberk, Josef; Stefanov, Petar; Vozar, Jozef; Sebela, Stanka; Petro, Lubomir; Bella, Pavel; Gaal, Ludovit; Ormukov, Cholponbek;
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Your search for younger dryas (Keyword) returned 16 results for the whole karstbase:
Showing 1 to 15 of 16
Controversy over the great flood hypotheses in the Black Sea in light of geological, paleontological, and archaeological evidence, , Yankohombach Valentina, Gilbert Allan S. , Dolukhanov Pavel,
Legends describing a Great Flood are found in the narratives of several world religions, and the biblical account of Noah's Flood is the surviving heir to several versions of the ancient Mesopotamian Flood Myth. Recently, the story of the biblical deluge was connected to the Black Sea, together with the suggestion that the story's pre-Mesopotamian origins might be found in the Pontic basin [Ryan, W.B.F., Pitman, III, W.C., 1998. Noah's Flood: The New Scientific Discoveries About the Event That Changed History. Simon and Schuster, New York]. Based on the significance of this flood epic in the Judeo-Christian tradition, popular interest surged following publication of the idea.Currently, two Great Flood scenarios have been proposed for the Black Sea: (1) an Early Holocene event caused by catastrophic Mediterranean inflow at 7.2 ky BP (initial hypothesis of [Ryan et al., 1997. An abrupt drowning of the Black Sea shelf. Marine Geology 138, 119-126]) or 8.4 ky BP (modified hypothesis of [Ryan et al., 2003. Catastrophic flooding of the Black Sea. Annual Review of Earth and Planetary Science 31, 525-554.); and (2) a Late Pleistocene event brought on by Caspian influx between 16 and 13 ky BP [Chepalyga, A.L., 2003. Late glacial Great Flood in the Black Sea and Caspian Sea. GSA Annual Meeting and Exposition, 2-5 November 2003, Seattle, USA, p. 460]. Both hypotheses claim that the massive inundations of the Black Sea basin and ensuing large-scale environmental changes had a profound impact on prehistoric human societies of the surrounding areas, and both propose that the event formed the basis for the biblical Great Flood legend.This paper attempts to determine whether the preponderance of existing evidence sustains support for these Great Floods in the evolution of the Black Sea. Based upon established geological and paleontological data, it finds that the Late Pleistocene inundation was intense and substantial whereas the Early Holocene sea-level rise was not. Between 16 and 13 ky BP, the Late Neoeuxinian lake (the Late Pleistocene water body in the Pontic basin pre-dating the Black Sea) increased rapidly from ~-14 to -50 m (below the present level of the Black Sea), then rose gradually to ~-20 m by about 11 ky BP. At 11-10 ky BP (the Younger Dryas), it dropped to ~-50 m. When the Black Sea re-connected with the Sea of Marmara at about 9.5 ky BP, inflowing Mediterranean water increased the Black Sea level very gradually up to ~-20 m, and in so doing, it raised the salinity of the basin and brought in the first wave of Mediterranean immigrants. These data indicate no major drawdown of the Black Sea after the Younger Dryas, and they do not provide evidence for any catastrophic flooding of the Black Sea in the Early Holocene.In addition, available archaeological and paleoenvironmental evidence from the Pontic region reveal no recognizable changes in population dynamics between 14 and 6 ky BP that could be linked to an inundation of large magnitude [Dolukhanov, P., Shilik, K., 2006. Environment, sea-level changes, and human migrations in the northern Pontic area during late Pleistocene and Holocene times. In: Yanko-Hombach, V., Gilbert, A.S., Panin, N., Dolukhanov, P.M. (Eds.), The Black Sea Flood Question: Changes in Coastline, Climate, and Human Settlement. Springer, Dordrecht, pp. 297-318; Stanko, V.N., 2006. Fluctuations in the level of the Black Sea and Mesolithic settlement of the northern Pontic area. In: Yanko-Hombach, V., Gilbert, A.S., Panin, N., Dolukhanov, P.M. (Eds.), The Black Sea Flood Question: Changes in Coastline, Climate, and Human Settlement. Springer, Dordrecht, pp. 371-385]. More specifically, Mesolithic and early Neolithic archaeological data in southeastern Europe and Ukraine give no indications of shifts in human subsistence or other behavior at the time of the proposed catastrophic flood in the Early Holocene [Anthony, D., 2006. Pontic-Caspian Mesolithic and Early Neolithic societies at the time of the Black Sea Flood: A small audience and small effects. In: Yanko-Hombach, V., Gilbert, A.S., Panin, N., Dolukhanov, P.M. (Eds.), The Black Sea Flood Question: Changes in Coastline, Climate, and Human Settlement. Springer, Dordrecht, pp. 345-370; Dergachev and Dolukhanov, 2006. The Neolithization of the North Pontic area and the Balkans in the context of the Black Sea Floods. In: Yanko-Hombach, V., Gilbert, A.S., Panin, N., Dolukhanov, P.M. (Eds.), The Black Sea Flood Question: Changes in Coastline, Climate, and Human Settlement. Springer, Dordrecht, pp. 489-514]

Coral Record of Equatorial Sea-Surface Temperatures During the Penultimate Deglaciation at Huon Peninsula, 1999, Mcculloch Malcolm T. , Tudhope Alexander W. , Esat Tezer M. , Mortimer Graham E. , Chappell John, Pillans Bradley, Chivas Allan R. , Omura Akio,
Uplifted coral terraces at Huon Peninsula, Papua New Guinea, preserve a record of sea level, sea-surface temperature, and salinity from the penultimate deglaciation. Remnants have been found of a shallow-water reef that formed during a pause, similar to the Younger Dryas, in the penultimate deglaciation at 130,000 2000 years ago, when sea level was 60 to 80 meters lower than it is today. Porites coral, which grew during this period, has oxygen isotopic values and strontium/calcium ratios that indicate that sea-surface temperatures were much cooler (22 degrees 2 degrees C) than either Last Interglacial or present-day tropical temperatures (29 degrees 1 degrees C). These observations provide further evidence for a major cooling of the equatorial western Pacific followed by an extremely rapid rise in sea level during the latter stages of Termination II

Weichselian palaeoclimate and palaeoenvironment in Europe: background for palaeogroundwater formation, 2001, Vaikmae R. , Edmunds W. M. , Manzano M. ,
A review is given of palaeoclimatic and palaeoenvironmental evidence across Europe for the Weichselian period relevant to interpreting the emplacement and circulation of groundwaters. In addition, this provides the background against which the evidence of past climates and environments contained in groundwaters in coastal areas of Europe, from the Baltic to the Atlantic Ocean may be compared. For much of the Weichselian, although significantly colder than at present, conditions were favourable for the recharge of groundwater, as shown, for example, by periods of speleothem growth. During the last glacial maximum (LGM) recharge is likely to have ceased over much of permafrost-covered Europe, although shallow groundwater recharge from meltwater (generated by the geothermal gradients) could have taken place beneath the ice where pressure relief through tunnel valleys may have occurred. Modern recharge could have started as early as 13 14C ka BP, but probably interrupted by the Younger Dryas between 11 and 10 14C ka BP. In the Baltic areas, ice-dammed lakes inhibited the start of the modern hydrogeological regimes until c. 10.3 14C ka BP. Tundra conditions prevailed over most of ice-free southern Europe at the time of the LGM. At this time the area south of the Portuguese-Spanish border retained a generally warm and relatively humid climate due to the maintenance of warmer sea-surface temperatures derived from Atlantic Ocean circulation. For most of coastal Europe, however, the most significant impact on groundwater circulation is likely to have been the lowering of sea levels that drained large areas of the shelf, such as the North Sea and the English Channel, and also had a significant impact on the Atlantic coast of the Iberian Peninsula where the maximum lowering of up to 130 m would have been experienced. This, together with the general changes in climate, would also have reorganized the atmospheric chemistry over sites in Europe that is likely to be recorded in the groundwater's chemical and isotopic signatures

A high-resolution speleothem record of climatic variability at the Allerod-Younger Dryas transition in Missouri, central United States., 2001, Denniston R. F. , Gonzalez L. A. , Asmerom Y. , Polyak V. , Reagan M. K. , Saltzman M. R.

Constraints on Black Sea outflow to the Sea of Marmara during the last glacial-interglacial transition, 2002, Major Candace, Ryan William, Lericolais Gilles, Hajdas Irka,
New cores from the upper continental slope off Romania in the western Black Sea provide a continuous, high-resolution record of sedimentation rates, clay mineralogy, calcium carbonate content, and stable isotopes of oxygen and carbon over the last 20[punctuation space]000 yr in the western Black Sea. These records all indicate major changes occurring at 15[punctuation space]000, 12[punctuation space]800, 8400, and 7100 yr before present. These results are interpreted to reflect an evolving balance between water supplied by melting glacial ice and other river runoff and water removed by evaporation and outflow. The marked retreat of the Fennoscandian and Alpine ice between 15[punctuation space]000 and 14[punctuation space]000 yr is recorded by an increase in clays indicative of northern provenance in Black Sea sediments. A short return toward glacial values in all the measured series occurs during the Younger Dryas cold period. The timing of the first marine inflow to the Black Sea is dependent on the sill depths of the Bosporus and Dardanelles channels. The depth of the latter is known to be -805 m, which is consistent with first evidence of marine inundation in the Sea of Marmara around 12[punctuation space]000 yr. The bedrock gorge of the Bosporus reaches depths in excess of -100 m (relative to present sea level), though it is now filled with sediments to depths as shallow as -32 m. Two scenarios are developed for the connection of the Black Sea with the Sea of Marmara. One is based on a deep Bosporus sill depth (effectively equivalent to the Dardanelles), and the other is based on a shallow Bosporus sill (less than -35 m). In the deep sill scenario the Black Sea's surface rises in tandem with the Sea of Marmara once the latter connected with the Aegean Sea, and Black Sea outflow remains continuous with inflowing marine water gradually displacing the freshwater in the deep basin. The increase in the [delta]18O of mollusk shells at 12[punctuation space]800 yr and the simultaneous appearance of inorganic calcite with low [delta]18O is compatible with such an early marine water influx causing periodic weak stratification of the water column. In the shallow sill scenario the Black Sea level is decoupled from world sea level and experiences rise and fall depending on the regional water budget until water from the rising Sea of Marmara breaches the shallow sill. In this case the oxygen isotope trend and the inorganic calcite precipitation is caused by increased evaporation in the basin, and the other changes in sediment properties reflect climate-driven river runoff variations within the Black Sea watershed. The presence of saline ponds on the Black Sea shelf circa 9600 yr support such evaporative draw-down, but a sensitive geochemical indicator of marine water, one that is not subject to temperature, salinity, or biological fractionation, is required to resolve whether the sill was deep or shallow

Soil types and eolian dust in high-mountainous karst of the Northern Calcareous Alps (Zugspitzplatt, Wetterstein Mountains, Germany), 2003, Kufmann C. ,
This, study deals with the soil formation on pure limestone in the high-mountainous karst of Wetterstein Mountains (Northern Calcareous Alps). The study area in detail covers the alpine (2000 to 2350 in) and the subnivale zone (2350 to 2600 in) of Zugspitzplatt, a tertiary paleosurface situated next to the highest summit of Germany (Zugspitze 2963 in). The formation of autochthonous soils is determined by the following parameters: uniform geology and geochemistry of Triassic limestone (CaCO3 MgCO3 greater than or equal to 98%), variable substrata (solid rock, debris, local moraine), hypsometric pattern of vegetation modified by microclimate and aspect, variety of micro-environments in karst relief. In the subnivale zone, only leptosols (lithic, skeletic) and regosols (calcaric, humic) occur, whereas in the alpine zone different stages of folic histosols and rendzic leptosols prevail due to the diversity of vegetation. The purity of limestone prevents a distinct contribution of residues to soil formation. Instead of expected A-B-C profiles, the residues are mixed with organic matter of folic horizons (O-OB-C). Only in karst depressions or on local moraines small Bt horizons (2 to 5 cm) occur. They mark a developed stage of folic histosol (O-OB-Bt-C) representing the climax of autochthonous mineral soil genesis in the study area. Special features are brown deposits (mean thickness 30 cm) covering large parts of the alpine zone. On the basis of mineralogical (X-ray diffraction, heavy minerals) and pedological data (grain size, soil chemistry), eolian origin is indicated. The resulting soils are classified as loess loam-like cambisols (Ah-Bw-2(Bt)-2C) and are related to late glacial loess deposition (Egesen-Stade of Younger Dryas). The abundance of mica and silt in the surface layers and the grain size distribution of snow dust samples prove that dust influx by southerly winds is still continuing. The major sources for both late glacial and present-day dust are magmatic and metamorphic rock formations of the Central Alps. Additionally, local dust transport from adjacent outcrops of Jurassic and Lower Cretaceous sediments is evident. (C) 2003 Elsevier Science B.V. All rights reserved

Prolonged wet period in the southwestern United States through the Younger Dryas, 2004, Polyak Victor J. , Rasmussen Jessica B. T. , Asmerom Yemane,
The Younger Dryas was one of the more dramatic climatic transitions ever recorded. How these types of climatic shifts are expressed in continental interiors is of primary scientific interest and of vital societal concern. Here we present a speleothem-based absolutely dated record (using uranium-series data) of climate change for the southwestern United States from growth chronology of multiple speleothems. The stalagmite growth represents the onset of wetter climate (12,500 yr B.P.) soon after the start of the Younger Dryas; the wetter climate persisted a millennium beyond the termination of the Younger Dryas. This wet cycle is likely related to a more southern positioning of the polar jet stream in response to cooler Northern Hemisphere climate. The end of the wet period coincides with the peak of the Holocene summer insolation maximum ca. 10,500 yr B.P. The Allerod (prior to the Younger Dryas), which corresponds to Clovis occupation in the southwestern United States, was drier in comparison and seems in line with a climatic contribution to megafauna extinction

Climatic Control of Riverine and Seawater Uranium-Isotope Ratios, 2004, Robinson Laura F. , Henderson Gideon M. , Hall Lisa, Matthews Iain,
The large variation in the ratio of uranium-234 to uranium-238 (234U/238U) in rivers is not well understood, but may provide information about past weathering and rainfall and is important because it controls seawater (234U/238U). Here, we demonstrate the importance of physical weathering and rainfall for (234U/238U), using rivers from South Island, New Zealand. These data allow interpretation of an existing speleothem (234U/238U) record and suggest that New Zealand glacier advance 13,000 years ago was influenced by increased rainfall rather than by Younger Dryas-like cooling. A model of seawater (234U/238U) during glacial cycles indicates that rejection of corals based on modern (234U/238U) {} <0.01 is not merited and may reject the highest quality ages

A Late-glacial and Holocene record of climatic change from a Swiss peat humification profile, 2004, Roosbarraclough Fiona, Van Der Knaap W. O. , Van Leeuwen J. F. N. , Shotyk W. ,
Colorimetric measurements of alkaline extracts from two Swiss peat cores have provided a complete 14500-year-long record of peat humification, a proxy of effective precipitation. Peat from the cold Younger Dryas (11050-9550 cal. bc) was well preserved despite low levels of precipitation. A particularly dry period, peaking at c. 7100 cal. bc, is indicated by well-decomposed peat. Peat from c. 6750-4250 cal. bc shows a low degree of decomposition, indicating a wet bog surface despite relatively warm temperatures and therefore indicating high levels of precipitation. A sharp transition to higher levels of decomposition c. 4450-3750 cal. bc indicates a major transition to a drier bog surface. Subsequently, peat humification generally decreases towards the end of the deeper profile (c. cal. ad 1050), indicating a gradual return to wetter conditions. This gradual decrease is punctuated by periods of particularly low humification which appear to be due to shifts to higher levels of effective precipitation from c. 2500 to 1350 cal. bc, c. 1050 to 550 cal. bc, centered around 150 cal. bc, and from c. cal. ad 550 onwards. Anthropogenic influences appear to have affected peat humification at the site at least since the Middle Ages. This study indicates that humification in colder regions/time periods could be more affected by temperature than precipitation and vice versa

Variability of Southwest Indian summer monsoon precipitation during the Bolling-Allerod, 2005, Sinha Ashish, Cannariato Kevin G. , Stott Lowell D. , Li Hong Chun, You Chen Feng, Cheng Hai, Edwards R. Lawrence, Singh Indra B. ,
We have generated a high-resolution (<20 yr) 230Th-dated stalagmite oxygen isotope record from Timta Cave in the western Himalaya in India that documents Southwest Indian summer monsoon (ISM) precipitation variations during the Bolling-Allerod interstadial from 15.2 to 11.7 ka. Compared with the glacial and Younger Dryas, ISM precipitation was enhanced during the Bolling-Allerod. ISM precipitation was apparently coupled to variations in the East Asian monsoon and North Atlantic climate on millennial and multicentennial time scales during the deglaciation. Analyses of a high growth rate interval (<2.5 yr resolution) encompassing the late Bolling-early Allerod suggest that multidecadal monsoon variability was an important aspect of ISM behavior at that time. The frequency spectrum of ISM precipitation during this time interval is similar to that of the {Delta}14C record and other ISM precipitation records during the latest Holocene. This raises the hypothesis that multidecadal climate dynamics during the late Bolling-early Allerod may have been similar to those that operated during the last several millennia, even though the boundary conditions of these two time intervals were very different

Late glacial to Holocene climate and sedimentation history in the NW Black Sea, 2005, Bahr A, Lamy F, Arz H, Kuhlmann H, Wefer G,
Gravity cores from the continental slope in the northwestern Black Sea were studied using high-resolution stable isotope, grain size and XRF-scanning data. The measurements provide a 30 000 years AMS 14C-dated record of variations in the hydrological regime of the Black Sea and give insight into changing paleoenvironments in the surrounding areas. Stable climatic conditions during the Last Glacial Maximum were followed by a series of meltwater pulses most likely originating from the Scandinavian ice sheet between 18 000 and 15 500 yr BP.1 This meltwater input rose the level of the Caspian Sea to a point that Caspian water could spill into the Black Sea via the Manych-depression north of the Caucasian mountains. High-frequency oscillations in the XRF-data during this period suggest a probable link to the arctic climate regime. Later, during the Bolling/Allerod and the early Holocene, prevailing high temperatures led to authigenic calcite precipitation through increased phytoplankton activity, interrupted by the Younger Dryas and the '8200 yr BP cold event' with dominant clastic sedimentation

Stable isotope investigations on speleothems from different cave systems in Germany, 2005, Nordhoff, P.

Seven speleothems from six independent cave systems in Germany were investigated on their suitability as paleoclimatic archives. The caves are located in the Jurassic Limestones of the Swabian/Franconian Alb (southern Germany) and in a small-scale Devonian (reef) complex of the Harz Mountains (northern Germany). Based on the chronological control using 234U/230Th (TIMS) ages, δ18O/δ13C timeseries of the speleothems were established and related to known paleoclimatic events.
Results of the present-day assessment of the cave systems demonstrated that the cave temperature responses; the stable isotopic abundances of the dripwater, and present-day cave calcites reflect mean annual surface air temperatures as well as established isotopic equilibrium conditions during cave calcite precipitation. However, existing biases have been monitored but most of them may be deduced to anthropogenic influences like mining operations (Zaininger-Cave, Swabian Alb) or showcave business (Hermann’s- and Baumann’s-Cave, Harz Mountains). Although the scenarios leave partially an imprint on present-day spelean calcites, like the indicated non-equilibrium conditions at the Zaininger-Cave, their temporal imprint is restricted very much to the last couple of decennial years and thus assumed not to influence the paleorecords at all. Since the δ18O compositions of present-day calcite precipitates are primarily controlled by temperature, the sites may thus be suitable for paleoclimatic investigations from a today perspective.
Since the paleorecords of the Hermann’s- and Baumann’s-Cave stalagmites (Harz Mountains) display ages, which are not in chronological order, a construction of timeseries was not possible.
Past stable isotopic equilibrium conditions of the remaining paleorecords were verified using the single layer “Hendy-Test” as well as δ18O/δ13C regression analyzes of the subsample profiles. Late Pleistocene growth periods were found in the Paleocave Hunas Stalagmite (79373 ± 8237 to 76872 ± 9686 a. B.P.; Franconian Alb) and the Cave Hintere Kohlhalde Stalagmite (44158 ± 3329 to 2709 ± 303 a B.P.; Swabian Alb). Unexpectedly, the latter displays no macroscopic visible growth hiatuses and was deposited continuously during the “cold” OIS 2 and the LGM. This has been interpreted owing to the special conditions and mode of vadose water circulation of a discontinuous permafrost zone which may have prevailed on the Swabian Alb during that time. Here, just like for the subsequent periods, principal changes in mean δ18O/δ13C and linear extension rates of the timeseries echoed the Boelling/Alleroed Interstadial and Younger Dryas cold phase. The comparison of coeval timeseries between the Cave Hintere Kohlhalde stalagmite, the Zaininger-Cave stalactite (both Swabian Alb) and the Mühlbach-Cave stalagmite (Franconian Alb) reveal some analogy such as the transitions from the Late Glacial to the Early Holocene between 10513 and 10587 cal. a B.P. for the Swabian Alb and 10227 cal. a B.P. for the Franconian Alb; the anomaly around 8.2 ka B.P. recorded in the Zaininger- and Mühlbach-Cave; and a climatic deterioration which leads to an almost simultaneous cessation of speleothem growth on the Swabian/Franconian Alb between 2.5 and 2.8 ka B.P.
Important changes of the stable isotopic composition occur together with changes in growth rate and in the macroscopic aspect of the investigated speleothems. This confirms that general climatic and environmental parameters control the recorded variations and that they are not owing to very local factors.


High resolution characterization of the Asian Monsoon between 146,000 and 99,000[no-break space]years B.P. from Dongge Cave, China and global correlation of events surrounding Termination II, 2006, Kelly Megan J. , Edwards R. Lawrence, Cheng Hai, Yuan Daoxian, Cai Yanjun, Zhang Meiliang, Lin Yushi, An Zhisheng,
Speleothem samples from Hulu (eastern China, 32[deg]30'N, 119[deg]10'E) and Dongge (southern China, 25[deg]17'N, 108[deg]5'E) Caves provide a nearly continuous record of the Asian monsoon over the last 160[no-break space]ka [Wang, Y.J., Cheng, H., Edwards, R.L., An, Z.S., Wu, J.Y., Shen, C.-C., Dorale, J.A., 2001. A high-resolution absolute-dated Late Pleistocene monsoon record from Hulu Cave, China. Science 294, 2345-2348; Yuan, D., Cheng, H., Edwards, R.L., Dykoski, C.A., Kelly, M.J., Zhang, M., Qing, J., Lin, Y., Wang, Y., Wu, J., Dorale, J.A., An, Z., Cai, Y., 2004. Timing, duration, and transitions of the last interglacial Asian Monsoon. Science 304, 575-578]. We have obtained higher resolution data in the interval between ~ 99 and 146[no-break space]ka B.P., providing a detailed account of [delta]18O variations over most of MIS 5 and the latter portion of MIS 6. Precise 230Th dating has replicated the chronology of the samples within error. The higher resolution data set confirms the timing of Asian Monsoon Termination II (the midpoint of the negative shift in [delta]18O marking the onset of the Last Interglacial Asian Monsoon), placing it at 129.0 0.9[no-break space]ka B.P. The bulk of this transition (~ 1.7[per mille sign]) took place within approximately 70[no-break space]years, with the total range of the transition being ~ 3[per mille sign]. The most abrupt portion of the shift in [delta]18O values (~ 1.1[per mille sign]) marking the end of the Last Interglacial Asian Monsoon occurred in ~ 120[no-break space]years, the midpoint of which is 120.7 1.0[no-break space]ka B.P. The Dongge Cave monsoon [delta]18O record over late MIS 6 exhibits a series of sub-orbital millennial-scale climate shifts that average 1.3[per mille sign] in magnitude and occur on average every 1.8[no-break space]ky. Abrupt shifts in [delta]18O of up to 1[per mille sign] also occurred throughout the Last Interglacial Asian Monsoon, with periods at multi-decadal to centennial timescales. Similar to the amplitude and periodicities of events found by Dykoski et al. [Dykoski, C.A., Edwards, R.L., Cheng, H., Yuan, D., Cai, Y., Zhang, M., Lin, Y., An, Z., Revenaugh, J., 2005. A high resolution, absolute-dated Holocene and deglacial Asian monsoon record from Dongge Cave, China. Earth and Planetary Science Letters 233, 71-86.] during the Holocene in the Dongge record, these shifts cover more than 1/2 of the amplitude of millennial-scale and multi-centennial-scale interstadial events during the Last Glacial Period [Wang, Y.J., Cheng, H., Edwards, R.L., An, Z.S., Wu, J.Y., Shen, C.-C., Dorale, J.A., 2001. A high-resolution absolute-dated Late Pleistocene monsoon record from Hulu Cave, China. Science 294, 2345-2348], and millennial-scale and multi-centennial-scale interstadial events during the Penultimate Glacial Period in China (this study). Abrupt decadal to millennial-scale climate events therefore appear to be a general feature of both glacial and interglacial climate. We demonstrate that monsoon intensity correlates well with atmospheric CH4 concentrations over the transition into the Bolling-Allerod, the Bolling-Allerod, and the Younger Dryas. In addition, we correlate an abrupt jump in CH4 concentration with Asian Monsoon Termination II. On the basis of this correlation, we conclude that the rise in atmospheric CO2, Antarctic warming, and the gradual portion of the rise in CH4 around Termination II occur within our 'Weak Monsoon Interval' (WMI), an extended interval of heavy [delta]18O between 135.5 1.0 and 129.0 1.0[no-break space]ka B.P., prior to Asian Monsoon Termination II and Northern Hemisphere warming. Antarctic warming over the millennia immediately preceding abrupt northern warming may result from the 'bipolar seesaw' mechanism. As such warming (albeit to a smaller extent) also preceded Asian Monsoon Termination I, the 'bipolar seesaw' mechanism may play a critical role in glacial terminations

Timing and dynamics of the last deglaciation from European and North African [delta]13C stalagmite profiles--comparison with Chinese and South Hemisphere stalagmites, 2006, Genty D, Blamart D, Ghaleb B, Plagnes V, Causse C, Bakalowicz M, Zouari K, Chkir N, Hellstrom J, Wainer K, Bourges F,
The last deglaciation and its climatic events, such as the Bolling-Allerod (BA) and the Younger-Dryas (YD), have been clearly recorded in the [delta]13C profiles of three stalagmites from caves from Southern France to Northern Tunisia. The three [delta]13C records, dated by thermal ionization mass spectrometric uranium-thorium method (TIMS), show great synchroneity and similarity in shape with the Chinese cave [delta]18O records and with the marine tropical records, leading to the hypothesis of an in-phase (between 15.5 and 16 ka ~0.5 ka) postglacial warming in the Northern Hemisphere, up to at least 45[deg]N. The BA transition appears more gradual in the speleothem records than in the Greenland records and the Allerod seems warmer than the Bolling, showing here close similarities with other marine and continental archives. A North-South gradient is observed in the BA trend: it cools in Greenland and warms in our speleothem records. Several climatic events are clearly recognizable: a cooler period at about 14 ka (Older Dryas (OD)); the Intra-Allerod Cold Period at about ~13.3 ka; the YD cooling onset between 12.7 and 12.90.3 ka. Similar to the BA, the YD displays a gradual climate amelioration just after its onset at 12.750.25 ka, up to the Preboreal, and is punctuated by a short climatic event at 12.15 ka. Even though the Southern Hemisphere stalagmite records seem to indicate that the postglacial warming started about ~3 ka1.8 ka earlier in New Zealand (~41 [deg]S), and about ~1 to ~2 ka earlier in South Africa (24.1 [deg]S), large age uncertainties, essentially due to slow growth rates, make the comparison still perilous. The overall [delta]13C speleothem record seems to follow a baseline temperature increase controlled by the increase in insolation and punctuated by cold events possibly due to the N-America freshwater lake discharges

The co-evolution of Black Sea level and composition through the last deglaciation and its paleoclimatic significance, 2006, Major Candace O. , Goldstein Steven L. , Ryan William B. F. , Lericolais Gilles, Piotrowski Alexander M. , Hajdas Irka,
The Black Sea was an inland lake during the last ice age and its sediments are an excellent potential source of information on Eurasian climate change, showing linkages between regionally and globally recognized millennial-scale climate events of the last deglaciation. Here, we detail changes from the last glacial maximum (LGM) through the transition to an anoxic marginal sea using isotopic (strontium and oxygen) and trace element (Sr/Ca) ratios in carbonate shells, which record changing input sources and hydrologic conditions in the basin and surrounding region. Sr isotope records show two prominent peaks between ~18 and 16 ka BP cal, reflecting anomalous sedimentation associated with meltwater from disintegrating Eurasian ice sheets that brought Black Sea level to its spill point. Following a sharp drop in Sr isotope ratios back toward glacial values, two stages of inorganic calcite precipitation accompanied increasing oxygen isotope ratios and steady Sr isotope ratios. These calcite peaks are separated by an interval in which the geochemical proxies trend back toward glacial values. The observed changes reflect negative water balance and lake level decline during relatively warm periods (Bolling-Allerod and Preboreal) and increasing river input/less evaporation, resulting in higher lake levels, during the intervening cold period (the Younger Dryas). A final shift to marine values in Sr and oxygen isotope ratios at 9.4 ka BP cal corresponds to connection with the global ocean, and marks the onset of sedimentation on the Black Sea continental shelf. This date for the marine incursion is earlier than previously suggested based on the appearance of euryhaline fauna and the onset of sapropel formation in the deep basin

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