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1. A seasonally resolved stalagmite δ18O record indicates the regional activity of tropical cyclones in Southeast China

Author

Lvfan Chen, Tianli Wang, Ashish Sinha, Fangyuan Lin, Huiru Tang, Hai Cheng, Richard Lawrence Edwards, and Liangcheng Tan

Subjects
Environmental sciences, GE1-350, Meteorology. Climatology, QC851-999
Abstract

Abstract Identifying tropical cyclone (TC) signatures in paleoclimate records enhances our understanding of long-term TC activity trends and the climatic factors influencing TC evolution. Stalagmites are considered promising archives for recording TC activity. However, despite the western North Pacific being the most TC-active ocean basin globally, it lacks stalagmite-based TC reconstructions. Here, we present a seasonally resolved stalagmite δ18O record from XRY cave in Southeast China, covering the period from 1951 to 2018 CE, to identify annual signals of strong TC activity. We propose that the minimum seasonal XRY δ18O value of each year can reconstruct regional TC activity, achieving an identification rate of 86% for strong TC years in study area. This demonstrates the feasibility of using stalagmites for TC reconstruction in Southeast China. Moreover, our research shows that inland stalagmites can still capture TC activity signals, which will promote the use of stalagmites in obtaining long-term records of post-landfall TC activity and inland impacts.

Published
2024
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2. Improvements in the determination of attogram-sized 231Pa in dissolved and particulate fractions of seawater via multi-collector inductively coupled plasma mass spectrometry

Author

Pu Zhang, Yanbin Lu, Zhe Zhang, Richard Lawrence Edwards, Robert Anderson, and Phoebe Lam

Subjects
231Pa, MC-ICP-MS, Suspended particulate matter, Precision, Reproducibility, Geography. Anthropology. Recreation, Geology, QE1-996.5
Abstract

Abstract A technique is developed to quantify the ultra-trace 231Pa (35–3904 ag) concentration in seawater using multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS). The method is a modification of the process developed by Shen et al. (Anal Chem 75(5):1075–1079, 2003. https://doi.org/10.1021/ac026247r ) and extends it to the application of very low levels of actinides, and the 35 ag 231Pa can be measured with a precision of 15%. The total process blank for the water column was 0.02 ag/g, while the values of the large and small particles were ~ 30 ag/g. The ionization efficiency (ions generated/atom loaded) varies from 0.7 to 2.4%. The measurement time is 2–5 min. The amount of 231Pa needed to produce 231Pa data with an uncertainty of ± 0.8–15% is 35–3904 ag (~ 0.9 × 105 to 10 × 106 atoms). Replicate measurements of known standards and seawater samples demonstrate that the analytical precision approximates that expected from counting statistics, and that based on detection limits of 52 ag, 55 ag, and 28 ag, protactinium can be detected in a minimum seawater sample size of ~ 2.6 L for small suspended particulate matter (> 0.8 μm and 51 μm), and ~ 56 mL for filtered (

Published
2023
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3. Speleothem record from Pentadactylos cave (Cyprus): new insights into climatic variations during MIS 6 and MIS 5 in the Eastern Mediterranean

Author

F. Nader, Hai Cheng, Sophie Verheyden, Elisabeth Eiche, Therese Weissbach, Richard Lawrence Edwards, Philippe Claeys, Lauren Satterfield, Salih Gucel, Iris Charalambidou, Tobias Kluge, Carole Nehme, Identités et Différenciation de l'Environnement des Espaces et des Sociétés (IDEES), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-Université Le Havre Normandie (ULH), Normandie Université (NU)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche Interdisciplinaire Homme et Société (IRIHS), Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Normandie Université (NU)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU), Analytical, Environmental and Geo- Chemistry, Vrije Universiteit Brussel (VUB), Institute of Applied Geosciences [Karlsruhe], Karlsruhe Institute of Technology (KIT), Institut Royal des Sciences Naturelles de Belgique (IRSNB), Utrecht University [Utrecht], University of Nicosia, Institute of Environmental Physics [Heidelberg] (IUP), Universität Heidelberg [Heidelberg], Near East University, Xi'an Jiaotong University (Xjtu), School of Environmental and Forest Sciences, College of the Environment, University of Washington, Department of Analytical and Environmental Chemistry [Bruxelles], Vrije Universiteit Brussel [Bruxelles] (VUB), Analytical, Environmental & Geo-Chemistry, Chemistry, and Earth System Sciences

Subjects
010506 paleontology, Archeology, 010504 meteorology & atmospheric sciences, δ18O, Speleothem, Stalagmite, 01 natural sciences, Clumped isotopes, Altitude, [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry, Paleoclimatology, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, Ecology, Evolution, Behavior and Systematics, Fluid inclusions, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, Stable isotopes, Global and Planetary Change, geography, Eemian, geography.geographical_feature_category, δ13C, Geology, Middle-East, Last glacial/interglacial, Sapropel, Paleotemperatures, Speleothems, 13. Climate action, [SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology, Cyprus, Physical geography
Abstract

A new paleoclimate record from Cyprus gives valuable insights into climatic variations during Marine Isotope Stages (MIS) 6–5 for the East Mediterranean region. Two stalagmites from Pentadactylos cave in the Kyrenia mountain range (800 m altitude) in Cyprus grew from 174.6 ± 0.7 to 112.2 ± 0.5 ka BP with major hiatuses at 163–142 and 132–128 ka. During early MIS6 the stalagmite suggests through a relatively low growth rate (57–5 mm/ka) and variable, but rather negative d18O that climate conditions were highly variable on a millennial scale, with wet and cold climate conditions during Sapropel 6 deposition. At the end of MIS6 (141–132 ka), growth rate varied from 123 to 18 mm/ka and less negative δ 18 O c suggests general dry/cold conditions followed by a growth stop during H11. The onset of MIS5e is marked by the highest growth rate (217 mm/ka). The most negative δ18O values at the onset and during the Eemian wet period in Cyprus are driven mostly by the source effect (Sapropel 5) and enhanced rainfall amounts. Stable conditions during MIS 5e were rather short as shown in the growth and isotopic signal, consistent with other EM records. After 122 ka, growth decreased drastically (8–2 mm/ka) and a slow deterioration of the soil cover is suggested from continuously less negative δ13C values. Fluid inclusion d18O shows a clear shift (4–5‰) between end-MIS 6 and MIS 5e. Clumped isotopes measurements indicate kinetic effects between calcite and water of up to ∼1‰. After correction for kinetic effects using Δ47, a minimum estimate for the MIS 6–5 temperature shift in the EM is ca. 9 °C. Similarly, drastic changes in rainfall amounts are inferred from measured (fluid inclusion) and calculated water d18O.

Published
2020
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4. A Continuous Record of Central Tropical Pacific Climate Since the Midnineteenth Century Reconstructed From Fanning and Palmyra Island Corals: A Case Study in Coral Data Reanalysis

Author

Kim M. Cobb, Christopher D. Charles, Hai Cheng, Tapio Schneider, Gerald H. Haug, Niko Westphal, Richard Lawrence Edwards, and Sara C. Sanchez

Subjects
Tropical pacific, Atmospheric Science, Geography, Centennial, Climatology, Coral, Paleontology, Hindcast, Climate model, Climate record, Extended time, Oceanography, Proxy (climate)
Abstract

Accurate estimation of central tropical Pacific (CTP) climate variability on interannual to centennial time scales is required for robust projections of future global climate trends. Here we outline an approach that blends instrumental and coral proxy observations to yield a continuous, monthly resolved record of climate evolution in the CTP spanning the past 160 years. We concatenate coral oxygen isotope (δ¹⁸O) records from multiple living and fossil corals collected from Fanning Island (4°N, 160°W) and Palmyra Island (5°N; 162°W) located in the heart of the El Nino–Southern Oscillation. We use the regularized expectation maximization (RegEM) method to impute missing data across short gaps of 5 to 23 years within and beyond individual coral records. The resulting monthly resolved Fanning/Palmyra Island climate record spans continuously from 1863 to 2016 and provides an example of how extended time series can be built from shorter coral segments. The extended record highlights the strong trend toward warmer and wetter mean conditions in late twentieth century, in agreement with the majority of climate model hindcast simulations. The continuous reconstruction also enables a direct comparison of four exceptionally strong El Nino events (1877–1878, 1940–1941, 1997–1998, and 2015–2016). Three of these very strong El Nino events in the CTP featured a precursor warm event in the prior year and that may have favored the development of a strong El Nino event.

Published
2020

5. Hydro-climatic variability in the southwestern Indian Ocean between 6000 and 3000 years ago

Author

Pengzhen Duan, Hai Cheng, Ashish Sinha, Christoph Spötl, Richard Lawrence Edwards, Youfeng Ning, Hanying Li, Jayant Biswas, Aurèle Anquetil André, Arnaud Meunier, and Gayatri Kathayat

Subjects
lcsh:GE1-350, Global and Planetary Change, geography.geographical_feature_category, 010504 meteorology & atmospheric sciences, Stratigraphy, lcsh:Environmental protection, Northern Hemisphere, Paleontology, Climate change, Speleothem, Subtropics, 010502 geochemistry & geophysics, 01 natural sciences, Proxy (climate), Indian ocean, Geography, lcsh:Environmental pollution, 13. Climate action, lcsh:TD172-193.5, lcsh:TD169-171.8, Physical geography, Southern Hemisphere, Holocene, lcsh:Environmental sciences, 0105 earth and related environmental sciences
Abstract

The “4.2 ka event” is frequently described as a major global climate anomaly between 4.2 and 3.9 ka, which defines the beginning of the current Meghalayan age in the Holocene epoch. The “event” has been disproportionately reported from proxy records from the Northern Hemisphere, but its climatic manifestation remains much less clear in the Southern Hemisphere. Here, we present highly resolved and chronologically well-constrained speleothem oxygen and carbon isotopes records between ∼6 and 3 ka from Rodrigues Island in the southwestern subtropical Indian Ocean, located ∼600 km east of Mauritius. Our records show that the 4.2 ka event did not manifest itself as a period of major climate change at Rodrigues Island in the context of our record's length. Instead, we find evidence for a multi-centennial drought that occurred near-continuously between 3.9 and 3.5 ka and temporally coincided with climate change throughout the Southern Hemisphere.

Published
2018

6. Evidence of thermophilisation and elevation-dependent warming during the Last Interglacial in the Italian Alps

Author

John Hellstrom, Christoph Spötl, Vanessa E. Johnston, Richard Lawrence Edwards, Petra Bajo, Paul Töchterle, Andrea Borsato, Silvia Frisia, Yuri Dublyansky, and Hai Cheng

Subjects
geography, Multidisciplinary, geography.geographical_feature_category, 010504 meteorology & atmospheric sciences, lcsh:R, Climate change, Speleothem, lcsh:Medicine, Glacier, Stalagmite, 15. Life on land, 010502 geochemistry & geophysics, 01 natural sciences, Article, Ice core, 13. Climate action, Interglacial, East Asian Monsoon, lcsh:Q, Physical geography, Water cycle, lcsh:Science, Geology, 0105 earth and related environmental sciences
Abstract

Thermophilisation is the response of plants communities in mountainous areas to increasing temperatures, causing an upward migration of warm-adapted (thermophilic) species and consequently, the timberline. This greening, associated with warming, causes enhanced evapotranspiration that leads to intensification of the hydrological cycle, which is recorded by hydroclimate-sensitive archives, such as stalagmites and flowstones formed in caves. Understanding how hydroclimate manifests at high altitudes is important for predicting future water resources of many regions of Europe that rely on glaciers and snow accumulation. Using proxy data from three coeval speleothems (stalagmites and flowstone) from the Italian Alps, we reconstructed both the ecosystem and hydrological setting during the Last Interglacial (LIG); a warm period that may provide an analogue to a near-future climate scenario. Our speleothem proxy data, including calcite fabrics and the stable isotopes of calcite and fluid inclusions, indicate a +4.3 ± 1.6 °C temperature anomaly at ~2000 m a.s.l. for the peak LIG, with respect to present-day values (1961–1990). This anomaly is significantly higher than any low-altitude reconstructions for the LIG in Europe, implying elevation-dependent warming during the LIG. The enhanced warming at high altitudes must be accounted for when considering future climate adaption strategies in sensitive mountainous regions.

Published
2018
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7. Three distinct Holocene intervals of stalagmite deposition and nondeposition revealed in NW Madagascar, and their paleoclimate implications

Author

Loren Bruce Railsback, M. Razanatseheno, Ny Riavo G. Voarintsoa, Hai Cheng, Gayatri Kathayat, A.F.M. Rakotondrazafy, Lixin Wang, Richard Lawrence Edwards, George A. Brook, and Xianglei Li

Subjects
lcsh:GE1-350, Global and Planetary Change, geography, geography.geographical_feature_category, 010504 meteorology & atmospheric sciences, Stratigraphy, Intertropical Convergence Zone, lcsh:Environmental protection, Paleontology, Stalagmite, Hiatus, 010502 geochemistry & geophysics, 01 natural sciences, Sedimentary depositional environment, Cave, lcsh:Environmental pollution, Paleoclimatology, lcsh:TD172-193.5, lcsh:TD169-171.8, Southern Hemisphere, Holocene, Geology, lcsh:Environmental sciences, 0105 earth and related environmental sciences
Abstract

Petrographic features, mineralogy, and stable isotopes from two stalagmites, ANJB-2 and MAJ-5, respectively from Anjohibe and Anjokipoty caves, allow distinction of three intervals of the Holocene in NW Madagascar. The Malagasy early Holocene (between ca. 9.8 and 7.8 ka) and late Holocene (after ca. 1.6 ka) intervals (MEHI and MLHI, respectively) record evidence of stalagmite deposition. The Malagasy middle Holocene interval (MMHI, between ca. 7.8 and 1.6 ka) is marked by a depositional hiatus of ca. 6500 years. Deposition of these stalagmites indicates that the two caves were sufficiently supplied with water to allow stalagmite formation. This suggests that the MEHI and MLHI intervals may have been comparatively wet in NW Madagascar. In contrast, the long-term depositional hiatus during the MMHI implies it was relatively drier than the MEHI and the MLHI. The alternating wet–dry–wet conditions during the Holocene may have been linked to the long-term migrations of the Intertropical Convergence Zone (ITCZ). When the ITCZ's mean position is farther south, NW Madagascar experiences wetter conditions, such as during the MEHI and MLHI, and when it moves north, NW Madagascar climate becomes drier, such as during the MMHI. A similar wet–dry–wet succession during the Holocene has been reported in neighboring locations, such as southeastern Africa. Beyond these three subdivisions, the records also suggest wet conditions around the cold 8.2 ka event, suggesting a causal relationship. However, additional Southern Hemisphere high-resolution data will be needed to confirm this.

Published
2017

8. NALPS: a precisely dated European climate record 120–60 ka

Author

Xianfeng Wang, Richard Lawrence Edwards, Christoph Spötl, Ronny Boch, Philipp Häuselmann, and Hai Cheng

Subjects
010506 paleontology, 010504 meteorology & atmospheric sciences, lcsh:Environmental protection, Stratigraphy, Climate change, Stalagmite, 010502 geochemistry & geophysics, 01 natural sciences, Isotopes of oxygen, lcsh:Environmental pollution, Ice core, lcsh:TD169-171.8, Glacial period, Stadial, lcsh:Environmental sciences, 0105 earth and related environmental sciences, lcsh:GE1-350, Global and Planetary Change, geography, geography.geographical_feature_category, Paleontology, Science::Geology::Volcanoes and earthquakes [DRNTU], 13. Climate action, Climatology, lcsh:TD172-193.5, Radiometric dating, Geology, Chronology
Abstract

Accurate and precise chronologies are essential in understanding the rapid and recurrent climate variations of the Last Glacial – known as Dansgaard-Oeschger (D-O) events – found in the Greenland ice cores and other climate archives. The existing chronological uncertainties during the Last Glacial, however, are still large. Radiometric age data and stable isotopic signals from speleothems are promising to improve the absolute chronology. We present a record of several precisely dated stalagmites from caves located at the northern rim of the Alps (NALPS), a region that favours comparison with the climate in Greenland. The record covers most of the interval from 120 to 60 ka at an average temporal resolution of 2 to 22 yr and 2σ-age uncertainties of ca. 200 to 500 yr. The rapid and large oxygen isotope shifts of 1 to 4.5‰ occurred within decades to centuries and strongly mimic the Greenland D-O pattern. Compared to the updated Greenland ice-core timescale (GICC05modelext) the NALPS record confirms the timing of rapid warming and cooling transitions between 118 and 106 ka, but suggests younger ages for D-O events between 106 and 60 ka. As an exception, the timing of the rapid transitions into and out of the stadial following GI 22 is earlier in NALPS than in the Greenland ice-core timescale. In addition, there is a discrepancy in the duration of this stadial between the ice-core and the stalagmite chronology (ca. 2900 vs. 3650 yr). The short-lived D-O events 18 and 18.1 are not recorded in NALPS, provoking questions with regard to the nature and the regional expression of these events. NALPS resolves recurrent short-lived climate changes within the cold Greenland stadial and warm interstadial successions, i.e. abrupt warming events preceding GI 21 and 23 (precursor-type events) and at the end of GI 21 and 25 (rebound-type events), as well as intermittent cooling events during GI 22 and 24. Such superimposed events have not yet been documented outside Greenland.

Published
2018

9. Alpine permafrost thawing during the Medieval Warm Period identified from cryogenic cave carbonates

Author

Richard Lawrence Edwards, Gina E. Moseley, M. Borreguero, Christoph Spötl, and Marc Luetscher

Subjects
lcsh:GE1-350, Calcite, geography, geography.geographical_feature_category, Stable isotope ratio, lcsh:QE1-996.5, Geochemistry, Permafrost, Karst, lcsh:Geology, chemistry.chemical_compound, chemistry, Cave, Glacial period, Precipitation, Geomorphology, lcsh:Environmental sciences, Holocene, Geology, Earth-Surface Processes, Water Science and Technology
Abstract

Coarse crystalline cryogenic cave carbonates (CCCcoarse) dated to the last glacial period are common in central European caves and provide convincing evidence of palaeo-permafrost during this time. Little is known, however, about the exact nature of the environment in which CCCcoarse formed as no modern analogue setting is known. Here, we report the first findings of sub-recent, albeit inactive, CCCcoarse from a cave of the Western Alps which is located in the present-day permafrost zone. The globular shape and the presence of ubiquitous euhedral crystal terminations are comparable to previously described aggregates from the last glacial period and strongly suggest that these aggregates formed subaqueously in pools lacking agitation. Furthermore, stable isotope values of mm-sized spheroids point to calcite precipitation in a closed system with respect to CO2 strongly supporting the hypothesis of a cryogenic origin associated with the freezing of water ponds. U-series analyses revealed three clusters of late Holocene calcite precipitation intervals between 2129 and 751 a b2k. These ages correlate with known periods of elevated summer temperatures, suggesting that warming and thawing of the permafrozen catchment above the cave allowed water infiltration into the karst system. The growth of CCCcoarse resulted from the re-freezing of this water in the still cold karst cavities.

Published
2018

10. Importance of hydrothermal vents in scavenging removal of 230Th in the Nansen Basin

Author

M. M. Rutgers van der Loeff, Yanbin Lu, Viena Puigcorbé, Richard Lawrence Edwards, Ole Valk, S.B. Moran, Micha J.A. Rijkenberg, Sandra Gdaniec, K. H. Lepore, Walter Geibert, and Earth Observatory of Singapore

Subjects
010504 meteorology & atmospheric sciences, Nansen Basin, Geotraces, Social sciences::Geography [DRNTU], Particulates, 010502 geochemistry & geophysics, 01 natural sciences, Hydrothermal circulation, Geophysics, Oceanography, Arctic, Hydrothermal Scavenging, 13. Climate action, Ridge (meteorology), General Earth and Planetary Sciences, Environmental science, 14. Life underwater, Scavenging, 0105 earth and related environmental sciences, Hydrothermal vent
Abstract

In this study we present dissolved and particulate 230Th and 232Th results, as well as particulate 234Th data, obtained as part of the GEOTRACES central Arctic Ocean sections GN04 (2015) and IPY11 (2007). Samples were analyzed following GEOTRACES methods and compared to previous results from 1991. We observe significant decreases in 230Th concentrations in the deep waters of the Nansen Basin. We ascribe this nonsteady state removal process to a variable release and scavenging of trace metals near an ultraslow spreading ridge. This finding demonstrates that hydrothermal scavenging in the deep‐sea may vary on annual time scales and highlights the importance of repeated GEOTRACES sections.

Published
2018

11. The WAIS Divide deep ice core WD2014 chronology – Part 1: Methane synchronization (68–31 ka BP) and the gas age–ice age difference

Author

Joseph R. McConnell, Hai Cheng, Mai Winstrup, Eric J. Steig, Michael Sigl, Kurt M. Cuffey, Richard Lawrence Edwards, Gary D. Clow, Christo Buizert, Daniel Baggenstos, Todd Sowers, Rachael H. Rhodes, Jeffrey P. Severinghaus, Bradley R. Markle, Edward J. Brook, Tyler J. Fudge, and Kendrick C. Taylor

Subjects
010504 meteorology & atmospheric sciences, Stratigraphy, lcsh:Environmental protection, Speleothem, Antarctic ice sheet, F800, 010502 geochemistry & geophysics, 01 natural sciences, Physical Geography and Environmental Geoscience, Proxy (climate), Paleontology, Ice core, lcsh:Environmental pollution, Ice age, lcsh:TD169-171.8, lcsh:Environmental sciences, 0105 earth and related environmental sciences, lcsh:GE1-350, Global and Planetary Change, geography, geography.geographical_feature_category, Firn, Last Glacial Maximum, Climate Action, 13. Climate action, Climatology, lcsh:TD172-193.5, Geology, Chronology
Abstract

The West Antarctic Ice Sheet Divide (WAIS Divide, WD) ice core is a newly drilled, high-accumulation deep ice core that provides Antarctic climate records of the past ∼68 ka at unprecedented temporal resolution. The upper 2850 m (back to 31.2 ka BP) have been dated using annual-layer counting. Here we present a chronology for the deep part of the core (67.8–31.2 ka BP), which is based on stratigraphic matching to annual-layer-counted Greenland ice cores using globally well-mixed atmospheric methane. We calculate the WD gas age–ice age difference (Δage) using a combination of firn densification modeling, ice-flow modeling, and a data set of δ15N-N2, a proxy for past firn column thickness. The largest Δage at WD occurs during the Last Glacial Maximum, and is 525 ± 120 years. Internally consistent solutions can be found only when assuming little to no influence of impurity content on densification rates, contrary to a recently proposed hypothesis. We synchronize the WD chronology to a linearly scaled version of the layer-counted Greenland Ice Core Chronology (GICC05), which brings the age of Dansgaard–Oeschger (DO) events into agreement with the U/Th absolutely dated Hulu Cave speleothem record. The small Δage at WD provides valuable opportunities to investigate the timing of atmospheric greenhouse gas variations relative to Antarctic climate, as well as the interhemispheric phasing of the "bipolar seesaw".

Published
2015
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12. Variation in the Asian monsoon intensity and dry–wet conditions since the Little Ice Age in central China revealed by an aragonite stalagmite

Author

D. X. Yuan, Z. Y. Zhao, Yu-Shih Lin, Horng Sheng Mii, J. M. Qin, Hai Cheng, Ting-Yong Li, Richard Lawrence Edwards, W. Tang, Jian-Jun Yin, and Hong-Chun Li

Subjects
lcsh:GE1-350, Global and Planetary Change, geography, geography.geographical_feature_category, Stratigraphy, Intertropical Convergence Zone, lcsh:Environmental protection, Paleontology, North Pacific High, Stalagmite, Monsoon, lcsh:Environmental pollution, Climatology, Tropical monsoon climate, lcsh:TD172-193.5, Environmental science, Walker circulation, East Asian Monsoon, lcsh:TD169-171.8, Precipitation, lcsh:Environmental sciences
Abstract

This paper focuses on the climate variability in central China since AD 1300, involving: (1) a well-dated, 1.5-year resolution stalagmite δ18O record from Lianhua Cave, central China (2) links of the δ18O record with regional dry–wet conditions, monsoon intensity, and temperature over eastern China (3) correlations among drought events in the Lianhua record, solar irradiation, and ENSO (El Niño–Southern Oscillation) variation. We present a highly precise, 230Th / U-dated, 1.5-year resolution δ18O record of an aragonite stalagmite (LHD1) collected from Lianhua Cave in the Wuling Mountain area of central China. The comparison of the δ18O record with the local instrumental record and historical documents indicates that (1) the stalagmite δ18O record reveals variations in the summer monsoon intensity and dry–wet conditions in the Wuling Mountain area. (2) A stronger East Asian summer monsoon (EASM) enhances the tropical monsoon trough controlled by ITCZ (Intertropical Convergence Zone), which produces higher spring quarter rainfall and isotopically light monsoonal moisture in the central China. (3) The summer quarter/spring quarter rainfall ratio in central China can be a potential indicator of the EASM strength: a lower ratio corresponds to stronger EASM and higher spring rainfall. The ratio changed from 1 after 1950, reflecting that the summer quarter rainfall of the study area became dominant under stronger influence of the Northwestern Pacific High. Eastern China temperatures varied with the solar activity, showing higher temperatures under stronger solar irradiation, which produced stronger summer monsoons. During Maunder, Dalton and 1900 sunspot minima, more severe drought events occurred, indicating a weakening of the summer monsoon when solar activity decreased on decadal timescales. On an interannual timescale, dry conditions in the study area prevailed under El Niño conditions, which is also supported by the spectrum analysis. Hence, our record illustrates the linkage of Asian summer monsoon precipitation to solar irradiation and ENSO: wetter conditions in the study area under stronger summer monsoon during warm periods, and vice versa. During cold periods, the Walker Circulation will shift toward the central Pacific under El Niño conditions, resulting in a further weakening of Asian summer monsoons.

Published
2014

13. How well can we quantify dust deposition to the ocean?

Author

Laura F. Robinson, R. Shelley, Yumin Lu, Phoebe J. Lam, William M. Landing, Richard Lawrence Edwards, Daniel C. Ohnemus, Christopher T. Hayes, Martin Q. Fleisher, David Kadko, S.B. Moran, Peter L. Morton, Y. Lao, Kuo-Fang Huang, Christopher I. Measures, Hai Cheng, Robert F. Anderson, Earth Observatory of Singapore, Lamont-Doherty Earth Observatory (LDEO), Columbia University [New York], Institute of Global Environmental Change [China] (IGEC), Xi'an Jiaotong University (Xjtu), Department of Earth Sciences [Minneapolis], University of Minnesota [Twin Cities] (UMN), University of Minnesota System-University of Minnesota System, University of Southern Mississippi (USM), Academia Sinica, Florida International University [Miami] (FIU), University of California [Santa Cruz] (UC Santa Cruz), University of California (UC), Department of Earth, Ocean and Atmospheric Science [Tallahassee] (FSU | EOAS), Florida State University [Tallahassee] (FSU), Department of Oceanography [Honolulu], University of Hawai‘i [Mānoa] (UHM), University of Alaska [Fairbanks] (UAF), Bigelow Laboratory for Ocean Sciences, University of Bristol [Bristol], Laboratoire des Sciences de l'Environnement Marin (LEMAR) (LEMAR), Institut de Recherche pour le Développement (IRD)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Université de Brest (UBO)-Institut Universitaire Européen de la Mer (IUEM), Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), University of California [Santa Cruz] (UCSC), University of California, and Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Biogeochemical cycle, equatorial pacific, 010504 meteorology & atmospheric sciences, General Science & Technology, General Mathematics, Geotraces, chibido, General Physics and Astronomy, Geology [Science], 010502 geochemistry & geophysics, Atmospheric sciences, 01 natural sciences, Deep sea, Water column, boundary current systems, 14. Life underwater, Life Below Water, 0105 earth and related environmental sciences, Aerosols, [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, geography, geography.geographical_feature_category, north-atlantic transect, northeast tropical Atlantic, ACL, be-7 measurements, General Engineering, Trace element, Dust, Articles, biogeochemical cycles, global distribution, thorium isotopes, particle fluxes, Deposition (aerosol physics), Oceanography, GEOTRACES, 13. Climate action, Ridge, deep-ocean, Seawater, dust, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, aerosols, pacific-ocean
Abstract

WOS:000391139900001; International audience; Deposition of continental mineral aerosols (dust) in the Eastern Tropical North Atlantic Ocean, between the coast of Africa and the Mid-Atlantic Ridge, was estimated using several strategies based on the measurement of aerosols, trace metals dissolved in seawater, particulate material filtered from the water column, particles collected by sediment traps and sediments. Most of the data used in this synthesis involve samples collected during US GEOTRACES expeditions in 2010 and 2011, although some results from the literature are also used. Dust deposition generated by a global model serves as a reference against which the results from each observational strategy are compared. Observation-based dust fluxes disagree with one another by as much as two orders of magnitude, although most of the methods produce results that are consistent with the reference model to within a factor of 5. The large range of estimates indicates that further work is needed to reduce uncertainties associated with each method before it can be applied routinely to map dust deposition to the ocean. Calculated dust deposition using observational strategies thought to have the smallest uncertainties is lower than the reference model by a factor of 2-5, suggesting that the model may overestimate dust deposition in our study area. This article is part of the themed issue 'Biological and climatic impacts of ocean trace element chemistry'.

Published
2016
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14. Evidence of a prolonged drought ca. 4200 yr BP correlated with prehistoric settlement abandonment from the Gueldaman GLD1 Cave, Northern Algeria

Author

Fabien Dewilde, J.-L. Michelot, Farid Kherbouche, S. Hachi, D. Blamart, Hai Cheng, Édouard Régnier, Dominique Genty, Richard Lawrence Edwards, Jiaoyang Ruan, Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Géosciences Paris Sud (GEOPS), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), Centre National de Recherches Préhistoriques, Anthropologiques et Historiques (CNRPAH), Glaces et Continents, Climats et Isotopes Stables (GLACCIOS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Paléocéanographie (PALEOCEAN), Institute of Global Environmental Change [China] (IGEC), Xi'an Jiaotong University (Xjtu), Department of Earth Sciences [Minneapolis], University of Minnesota [Twin Cities] (UMN), University of Minnesota System-University of Minnesota System, Department of Geology and Geophysics [Minnesota], Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), and Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)

Subjects
Mediterranean climate, 010506 paleontology, 010504 meteorology & atmospheric sciences, Stratigraphy, lcsh:Environmental protection, Climate change, Stalagmite, 01 natural sciences, Mediterranean Basin, Panoply, law.invention, Cave, lcsh:Environmental pollution, law, Paleoclimatology, lcsh:TD169-171.8, Radiocarbon dating, Holocene, lcsh:Environmental sciences, 0105 earth and related environmental sciences, lcsh:GE1-350, Global and Planetary Change, geography, geography.geographical_feature_category, Paleontology, 15. Life on land, Archaeology, 13. Climate action, [SDU]Sciences of the Universe [physics], lcsh:TD172-193.5, Geology
Abstract

Middle Holocene cultures have been widely studied around the Eastern-Mediterranean basin in the last 30 years and past cultural activities have been commonly linked with regional climate changes. However, in many cases such linkage is equivocal, in part due to existing climatic evidence that has been derived from areas outside the distribution of ancient settlements, leading to uncertainty from complex spatial heterogeneity in both climate and demography. A few high-resolution well-dated paleoclimate records were recently established using speleothems in the Central and Eastern-Mediterranean basin, however, the scarcity of such records in the western part of the Mediterranean prevents us from correlating past climate evolutions across the basin and deciphering climate–culture relation at fine timescales. Here we report the first decadal-resolved Mid-Holocene climate proxy records from the Western-Mediterranean basin based on the stable carbon and oxygen isotopes analyses of two U/Th dated stalagmites from the Gueldaman GLD1 Cave in Northern Algeria. Comparison of our records with those from Italy and Israel reveals synchronous (multi) centennial dry phases centered at ca. 5600, ca. 5200 and ca. 4200 yr BP across the Mediterranean basin. New calibrated radiocarbon dating constrains reasonably well the age of rich anthropogenic deposits (e.g., faunal remains, pottery, charcoal) excavated inside the cave, which allows the comparison between in situ evidence of human occupation and of climate change. This approach shows that the timing of a prolonged drought at ca. 4400–3800 yr BP blankets the onset of cave abandonment shortly after ca. 4403 cal yr BP, supporting the hypothesis that a climate anomaly may have played a role in this cultural disruption.

Published
2016
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15. Calibration of speleothem δ18 O records against hydroclimate instrumental records in Central Brazil

Author

Mathias Vuille, Richard Lawrence Edwards, Valdir F. Novello, A. Siffedine, Christian Millo, Jean-Sébastien Moquet, William Santini, Francisco W. Cruz, R. Ventura Santos, Ivo Karmann, Michael Deininger, James Apaéstegui, Hai Cheng, Nicolás Misailidis Stríkis, Jean-Loup Guyot, Instituto de Geociências [São Paulo], Universidade de São Paulo = University of São Paulo (USP), Institut de Physique du Globe de Paris (IPGP), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Université de La Réunion (UR)-Institut de Physique du Globe de Paris (IPG Paris)-Centre National de la Recherche Scientifique (CNRS), Fluminense Federal University [Niterói], Géosciences Environnement Toulouse (GET), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Biogéochimie-Traceurs-Paléoclimat (BTP), Laboratoire d'Océanographie et du Climat : Expérimentations et Approches Numériques (LOCEAN), Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut Pierre-Simon-Laplace (IPSL (FR_636)), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut Pierre-Simon-Laplace (IPSL (FR_636)), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), LMI 'PALEOTRACES', IRD-UFF- Univ. of Antofagasta Chile, Department of Atmospheric and Environmental Sciences [Albany] (DAES), University at Albany [SUNY], State University of New York (SUNY)-State University of New York (SUNY), Institute of Global Environmental Change [China] (IGEC), Xi'an Jiaotong University (Xjtu), Department of Earth Sciences [Minneapolis], University of Minnesota [Twin Cities] (UMN), University of Minnesota System-University of Minnesota System, Universidade de São Paulo (USP), Institut national des sciences de l'Univers (INSU - CNRS)-IPG PARIS-Université Paris Diderot - Paris 7 (UPD7)-Université de La Réunion (UR)-Centre National de la Recherche Scientifique (CNRS), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD), Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Muséum national d'Histoire naturelle (MNHN)-Institut Pierre-Simon-Laplace (IPSL (FR_636)), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Muséum national d'Histoire naturelle (MNHN)-Institut Pierre-Simon-Laplace (IPSL (FR_636)), Centre National de la Recherche Scientifique (CNRS)-Université de La Réunion (UR)-Université Paris Diderot - Paris 7 (UPD7)-IPG PARIS-Institut national des sciences de l'Univers (INSU - CNRS), Centre National de la Recherche Scientifique (CNRS)-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Recherche pour le Développement (IRD)-Centre National d'Études Spatiales [Toulouse] (CNES), Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Muséum national d'Histoire naturelle (MNHN), and University of Minnesota [Twin Cities]

Subjects
Wet season, Global and Planetary Change, geography, geography.geographical_feature_category, 010504 meteorology & atmospheric sciences, δ18O, METEOROLOGIA AMBIENTAL, Speleothem, [PHYS.PHYS.PHYS-GEO-PH]Physics [physics]/Physics [physics]/Geophysics [physics.geo-ph], 15. Life on land, 010502 geochemistry & geophysics, Oceanography, Convergence zone, Monsoon, 01 natural sciences, Monitoring program, Cave, 13. Climate action, Climatology, Precipitation, Geology, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences
Abstract

δ 18 O in speleothems is a powerful proxy for reconstruction of precipitation patterns in tropical and sub-tropical regions. The aim of this study is to calibrate the δ 18 O record of speleothems against historical precipitation and river discharge data in central Brazil, a region directly influenced by the Southern Atlantic Convergence Zone (SACZ), a major feature of the South American Monsoon System (SAMS). The present work is based on a sub-annual resolution speleothem record covering the last 141 years (the period between the years 1870 and 2011) from a cave in central Brazil. The comparison of this record with instrumental hydroclimate records since 1921 allows defining a strong relationship between precipitation variability and stable oxygen isotope ratios from speleothems. The results from a monitoring program of climatic parameters and isotopic composition of rainfall and cave seepage waters performed in the same cave, show that the rain δ 18 O variability is dominated by the amount effect in this region, while δ 18 O drip water remains almost constant over the monitored period (1.5 years). The δ 18 O of modern calcite, on the other hand, shows clear seasonal variations, with more negative values observed during the rainy season, which implies that other factors also influence the isotopic composition of carbonate. However, the relationship between δ 18 O of carbonate deposits and rainwater is supported by the results from the comparison between speleothem δ 18 O records and historical hydroclimate records. A significant correlation between speleothem δ 18 O and monsoon rainfall variability is observed on sub-decadal time scales, especially for the monsoon period (DJFM and NDJFM), once the rainfall record have been smoothed with a 7–9 years running mean. This study confirms that speleothem δ 18 O is directly associated with monsoon rainfall variability in central Brazil. The relationship between speleothem δ 18 O records and hydroclimatic historical records allows approximation of the absolute changes in mean annual rainfall during the last millennia in the SACZ/SAMS domain.

Published
2016
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16. Long-term hydrological changes in northern Iberia (4.9–0.9 ky BP) from speleothem Mg/Ca ratios and cave monitoring (Ojo Guareña Karst Complex, Spain)

Author

Jorge O. Cáceres, J. A. Cruz, Paloma Gómez, L. Sánchez, María Jesús Turrero, Ana Isabel Ortega, A. Marín-Roldán, A. Garralón, Richard Lawrence Edwards, M.B. Muñoz-García, Javier Martín-Chivelet, and Ministerio de Economía y Competitividad (España)

Subjects
Global and Planetary Change, geography, geography.geographical_feature_category, Research groups, Paleohydrology, Soil Science, Speleothem, Karst, Geology, Pollution, Late Holocene, Mg/Ca, Cave, Environmental Chemistry, Physical geography, Iberia, Biogeosciences, Geomorphology, Earth-Surface Processes, Water Science and Technology
Abstract

An absolute-dated stalagmite from Kaite Cave (Ojo Guareña Karst Complex, N Spain) provides a nearly continuous, high-resolution record of a proxy of regional precipitation patterns through the 4.9–0.9 ka BP interval. This record is based on the Mg/Ca ratio of the calcite and its variation through the stalagmite stratigraphy, which is interpreted to be primarily driven by changes in precipitation amount. The calibration of the proxy is supported by the present-day monitoring carried out in the cave for the last 10 years, which reveals a robust inverse relationship between the inter-annual/inter-decadal variability of rainfall and the Mg concentration of dripwaters and precipitating speleothems. The record of paleoprecipitation, based on 2400 Mg/Ca measurements, shows strong variability at inter-annual to inter-decadal scales, and more subtle but significant changes at secular to millennial scales. This long-term paleohydrological evolution outlines five successive intervals with consistent trends, which are bounded by abrupt shifts in the regional precipitation. These shifts took place at 4.65, 4.2, 2.6, and 1.3 ka BP. Significantly, the intervals of maximum precipitation of the whole record (around 4.9–4.65, 2.6–2.45, and 1.3–1.1 ka BP) can be related with episodes of minimum solar activity and correlated with cold climatic events elsewhere., Contribution to research projects 28 CGL2010-21499-BTE and CGL2013-43257-R of the Spanish R+D National Program 29 (MINECO) and research groups ‘‘Paleoclimatology and Global Change’’ and ‘‘Laser Induced 30 Breakdown Spectroscopy (LIBS)’’ from the UCM (Spain).

Published
2015

17. Abrupt change of Antarctic moisture origin at the end of Termination II

Author

Enricomaria Selmo, Jérôme Chappellaz, Gareth J. Marshall, Sigfus J Johnsen, Jean Jouzel, Claire Waelbroeck, Kenji Kawamura, Aline Govin, Bénédicte Minster, Barbara Stenni, Olivier Cattani, Richard Lawrence Edwards, Bénédicte Lemieux-Dudon, K. Pol, Amaelle Landais, Hai Cheng, Regine Röthlisberger, Manfred Mudelsee, S. Falourd, Anna Lourantou, Valérie Masson-Delmotte, Gabrielle Dreyfus, Thomas Blunier, Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Glaces et Continents, Climats et Isotopes Stables (GLACCIOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Dipartimento di Scienze Geologiche [Trieste], Università degli studi di Trieste = University of Trieste, Centre for Ice and Climate [Copenhagen], Niels Bohr Institute [Copenhagen] (NBI), Faculty of Science [Copenhagen], University of Copenhagen = Københavns Universitet (UCPH)-University of Copenhagen = Københavns Universitet (UCPH)-Faculty of Science [Copenhagen], University of Copenhagen = Københavns Universitet (UCPH)-University of Copenhagen = Københavns Universitet (UCPH), CLIPS, Laboratoire de glaciologie et géophysique de l'environnement (LGGE), Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Department of Geology and Geophysics [Minnesota], University of Minnesota [Twin Cities] (UMN), University of Minnesota System-University of Minnesota System, Climat et Magnétisme (CLIMAG), National Institute of Polar Research [Tokyo] (NiPR), British Antarctic Survey (BAS), Natural Environment Research Council (NERC), Department of Bentho-pelagic processes, Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung (AWI), Climate Risk Analysis (CRAAM), Dipartimento di Scienze della Terra, Università degli studi di Parma = University of Parma (UNIPR), Paléocéanographie (PALEOCEAN), European Project: 39423,FP6-SUSTDEV,EPICA-MIS, Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS), Università degli studi di Trieste, University of Copenhagen = Københavns Universitet (KU)-University of Copenhagen = Københavns Universitet (KU)-Faculty of Science [Copenhagen], University of Copenhagen = Københavns Universitet (KU)-University of Copenhagen = Københavns Universitet (KU), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS), University of Minnesota [Twin Cities], Università degli studi di Parma [Parme, Italie], Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), University of Parma = Università degli studi di Parma [Parme, Italie], Masson Delmotte, V., Stenni, Barbara, Blunier, T., Cattani, O., Chappellaz, J., Cheng, H., Dreyfus, G., Edwards, R. L., Falourd, S., Govin, A., Kawamura, K., Johnsen, S. J., Jouzel, J., Landais, A., Lemieux Dudon, B., Lourantou, A., Marshall, G. J., Minster, B., Mudelsee, M., Pol, K., Röthlisberger, R., Selmo, E., and Waelbroeck, C.

Subjects
Time Factors, deuterium excess, water stable isotopes, deglaciations, bipolar seesaw, site temperature, source temperature, polar ice cores, 010504 meteorology & atmospheric sciences, Paleoclimate, Climate, Greenland, 010502 geochemistry & geophysics, 01 natural sciences, atmospheric moisture, Westerlies, Ice core, deuterium exce, Glacial period, Atlantic Ocean, Indian Ocean, deuterium, water stable isotope, seasonal variation, Multidisciplinary, termination II, European Project for Ice Coring in Antarctica, methane, article, Temperature, interglacial, priority journal, Climatology, Physical Sciences, Interglacial, Seasons, Geology, Environmental Monitoring, warming, Atmospheric circulation, Climate Change, Climate change, Antarctic Regions, deglaciation, Paleoclimatology, [SDU.STU.GM]Sciences of the Universe [physics]/Earth Sciences/Geomorphology, 0105 earth and related environmental sciences, Ice, Last interglacial, carbon dioxide, 13. Climate action, Antarctica
Abstract

The deuterium excess of polar ice cores documents past changes in evaporation conditions and moisture origin. New data obtained from the European Project for Ice Coring in Antarctica Dome C East Antarctic ice core provide new insights on the sequence of events involved in Termination II, the transition between the penultimate glacial and interglacial periods. This termination is marked by a north–south seesaw behavior, with first a slow methane concentration rise associated with a strong Antarctic temperature warming and a slow deuterium excess rise. This first step is followed by an abrupt north Atlantic warming, an abrupt resumption of the East Asian summer monsoon, a sharp methane rise, and a CO 2 overshoot, which coincide within dating uncertainties with the end of Antarctic optimum. Here, we show that this second phase is marked by a very sharp Dome C centennial deuterium excess rise, revealing abrupt reorganization of atmospheric circulation in the southern Indian Ocean sector.

Published
2010
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18. Timing and climatic impact of Greenland interstadials recorded in stalagmites from northern Turkey

Author

S. Badertscher, Albert Matter, Richard Lawrence Edwards, O. M. Göktürk, A. Fankhauser, Hai Cheng, Christoph C. Raible, Manfred Mudelsee, Robyn Pickering, Jan Kramers, Dominik Fleitmann, and Okan Tüysüz

Subjects
geography, geography.geographical_feature_category, biology, 530 Physics, Stalagmite, biology.organism_classification, Phase lag, Geophysics, Oceanography, Mediterranean sea, Cave, General Earth and Planetary Sciences, Ecosystem, Groenlandia, Stadial, Geology, Chronology
Abstract

A 50 kyr-long exceptionally well-dated and highly resolved stalagmite oxygen (δ 18O) and carbon (δ 13C) isotope record from Sofular Cave in northwestern Turkey helps to further improve the dating of Greenland Interstadials (GI) 1, and 3–12. Timing of most GI in the Sofular record is consistent within ±10 to 300 years with the “iconic” Hulu Cave record. Larger divergences (>500 years) between Sofular and Hulu are only observed for GI 4 and 7. The Sofular record differs from the most recent NGRIP chronology by up to several centuries, whereas age offsets do not increase systematically with depth. The Sofular record also reveals a rapid and sensitive climate and ecosystem response in the eastern Mediterranean to GI, whereas a phase lag of ∼100 years between climate and full ecosystem response is evident. Finally, results of spectral analyses of the Sofular isotope records do not support a 1,470-year pacing of GI.

Published
2009
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