A 60 000 year Greenland stratigraphic ice core chronology

Abstract. The Greenland Ice Core Chronology 2005 (GICC05) is a time scale based on annual layer counting of high-resolution records from Greenland ice cores. Whereas the Holocene part of the time scale is based on various records from the DYE-3, the GRIP, and the NorthGRIP ice cores, the glacial part is solely based on NorthGRIP records. Here we present an 18 kyr extension of the time scale such that GICC05 continuously covers the past 60 kyr. The new section of the time scale places the onset of Greenland Interstadial 12 (GI-12) at 46.9±1.0 kyr b2k (before year AD 2000), the North Atlantic Ash Zone 2 layer in GI-15 at 55.4±1.2 kyr b2k, and the onset of GI-17 at 59.4±1.3 kyr b2k. The error estimates are derived from the accumulated number of uncertain annual layers and can be regarded as 1σ uncertainties. In the 40–60 kyr interval the new time scale has a discrepancy with the Meese-Sowers GISP2 time scale of up to 2.4 kyr, whereas GICC05 compares well to the dating of the Hulu Cave record with absolute age differences of less than 800 years throughout the 60 kyr period. The new time scale is generally in close agreement with other independently dated records and reference horizons, such as the Laschamp geomagnetic excursion and the Kleegruben speleothem record from the Austrian Alps, suggesting high accuracy of both event durations and absolute age estimates.

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A 60 000 year Greenland stratigraphic ice core chronology

Climate of the Past ◽

10.5194/cp-4-47-2008 ◽

2008 ◽

Vol 4 (1) ◽

pp. 47-57 ◽

Cited By ~ 697

Author(s):

A. Svensson ◽

K. K. Andersen ◽

M. Bigler ◽

H. B. Clausen ◽

D. Dahl-Jensen ◽

...

Keyword(s):

North Atlantic ◽

Time Scale ◽

Ice Core ◽

Ice Cores ◽

The North ◽

Annual Layer ◽

Zone Ii ◽

Absolute Age ◽

Age Estimates ◽

New Time

Abstract. The Greenland Ice Core Chronology 2005 (GICC05) is a time scale based on annual layer counting of high-resolution records from Greenland ice cores. Whereas the Holocene part of the time scale is based on various records from the DYE-3, the GRIP, and the NorthGRIP ice cores, the glacial part is solely based on NorthGRIP records. Here we present an 18 ka extension of the time scale such that GICC05 continuously covers the past 60 ka. The new section of the time scale places the onset of Greenland Interstadial 12 (GI-12) at 46.9±1.0 ka b2k (before year AD 2000), the North Atlantic Ash Zone II layer in GI-15 at 55.4±1.2 ka b2k, and the onset of GI-17 at 59.4±1.3 ka b2k. The error estimates are derived from the accumulated number of uncertain annual layers. In the 40–60 ka interval, the new time scale has a discrepancy with the Meese-Sowers GISP2 time scale of up to 2.4 ka. Assuming that the Greenland climatic events are synchronous with those seen in the Chinese Hulu Cave speleothem record, GICC05 compares well to the time scale of that record with absolute age differences of less than 800 years throughout the 60 ka period. The new time scale is generally in close agreement with other independently dated records and reference horizons, such as the Laschamp geomagnetic excursion, the French Villars Cave and the Austrian Kleegruben Cave speleothem records, suggesting high accuracy of both event durations and absolute age estimates.

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1000 year ice-core records from Berkner Island, Antarctica

Annals of Glaciology ◽

10.3189/172756402781817176 ◽

2002 ◽

Vol 35 ◽

pp. 45-51 ◽

Cited By ~ 39

Author(s):

Robert Mulvaney ◽

Hans Oerter ◽

David A. Peel ◽

Wolfgang Graf ◽

Carol Arrowsmith ◽

...

Keyword(s):

Decadal Variability ◽

Ice Core ◽

Ice Cores ◽

Aerosol Deposition ◽

Climate History ◽

Joint Project ◽

The Past ◽

Annual Layer ◽

History Of ◽

Field Season

AbstractTwo medium-depth ice cores were retrieved from Berkner Island by a joint project between the Alfred-Wegener-Institut and the British Antarctic Survey in the 1994/95 field season. A 151m deep core from the northern dome (Reinwarthhöhe) of Berkner Island spans 700 years, while a 181 m deep core from the southern dome (Thyssenhöhe) spans approximately 1200 years. Both cores display clear seasonal cycles in electrical conductivity measurements, allowing dating by annual-layer counting and the calculation of accumulation profiles. Stable-isotope measurements (both δ18O and δD), together with the accumulation data, allow us to estimate changes in climate for most of the past millennium: the data show multi-decadal variability around a generally stable long-termmean. In addition, a full suite of major chemistry measurements is available to define the history of aerosol deposition at these sites: again, there is little evidence that the chemistry of the sites has changed over the past six centuries. Finally, we suggest that the southern dome, with an ice thickness of 950 m, is an ideal site from which to gain a climate history of the late stages of the last glacial and the deglaciation for comparison with the records from the deep Antarctic ice cores, and with other intermediate-depth cores such as Taylor Dome and Siple Dome.

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Luminescence age constraints on the Pleistocene-Holocene transition recorded in loess sequences

10.5194/egusphere-egu2020-16957 ◽

2020 ◽

Author(s):

Daniela Constantin ◽

Stefana-Madalina Sacaciu ◽

Viorica Tecsa ◽

Anca Avram ◽

Robert Begy ◽

...

Keyword(s):

Magnetic Susceptibility ◽

North Atlantic ◽

Ice Core ◽

Soil Formation ◽

Luminescence Dating ◽

The Holocene ◽

The Past ◽

The North ◽

The North Atlantic ◽

The Last Glacial

Here we investigate the timing of the last glacial loess - Holocene soil transition recorded in loess-paleosol sequences across the Chinese Loess Plateau, the SE European loess belt and the Central Great Plains, Nebraska, USA by applying comparative luminescence dating techniques on quartz and feldspars. Equivalent dose measurements were carried out using the single-aliquot regenerative-dose (SAR) protocol on silt (4&#8211;11 &#956;m) and sand-sized (63&#8211;90 &#956;m and coarser fraction when available) quartz. Feldspar infrared stimulated luminescence (IRSL) emitted by 4&#8211;11 &#956;m polymineral grains was measured using the post IR-IRSL290 technique.The paleoenvironmental transition from the last glacial loess to the current interglacial soil was characterized using magnetic susceptibility and its frequency dependence. Based on the OSL ages and the threshold of the magnetic signal enhancement the onset of soil formation started around Termination 1 (~17 ka in the North Atlantic) as observed in radiocarbon-dated regional benthic &#948;18O stacks (Stern and Lisiecki, 2014) but before the stratigraphic Pleistocene/Holocene transition dated at 11.7 ka in ice core records (Svensson et al., 2008).No major hiatuses in ages are identified in the investigated sites. A change in the sedimentation rate is generally observed at the Pleistocene-Holocene transition and no significant sedimentation change during the Holocene. Sedimentation rates of around 6 cm/ka are determined for the Holocene soil in most of the sites investigated.The magnetic susceptibility indicates a gradual increase in pedogenesis after Termination 1 (&#8764;17 ka in the North Atlantic). Based on this, we infer that the upbuilding soil formation prevailed over topdown soil formation during the Pleistocene-Holocene transition in the investigated sites (Roberts, 2008).&#160;ReferencesRoberts, H.M., 2008. The development and application of luminescence dating to loess deposits: a perspective on the past, present and future. Boreas 37, 483-507.Svensson, A., Andersen, K.K., Bigler, M., Clausen, H.B., Dahl-Jensen, D., Davies, S.M., Johnsen, S.J., Muscheler, R., Parrenin, F., Rasmussen, S.O., R&#246;thlisberger, R., Seierstad, I., Steffensen, J.P., Vinther, B.M., 2008.A 60 000 year Greenland stratigraphic ice core chronology. Climate of the Past 4, 47-57.Stern, J.V., Lisiecki, L.E., 2014. Termination 1 timing in radiocarbon-dated regional benthic &#948;18O stacks. Paleoceanography 29, 1127-1142.&#160;This project has received funding from the European Research Council (ERC) under the European Union&#8217;s Horizon 2020 research and innovation programme ERC-2015-STG (grant agreement No [678106]).

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Climatic and environmental events over the Last Termination, as recorded in The Netherlands: a review

Netherlands Journal of Geosciences – Geologie en Mijnbouw ◽

10.1017/s001677460002062x ◽

2002 ◽

Vol 81 (1) ◽

pp. 123-137 ◽

Cited By ~ 50

Author(s):

W.Z. Hoek ◽

S.J.P. Bohncke ◽

Keyword(s):

The Netherlands ◽

North Atlantic ◽

Time Scale ◽

Climate Changes ◽

Ice Cores ◽

The North ◽

Common Time ◽

Time Period ◽

Rapid Changes ◽

Environmental Events

AbstractThe Last Termination, or Weichselian Lateglacial (ca 15–10 ka cal. BP), is a time period with rapid changes in climate and environment. The oxygen-isotope records of the Greenland ice-cores are regarded as the most complete climate proxy for the North Atlantic region. In The Netherlands several other proxies have been investigated and dated in great detail over the last few decades. However, changes registered in the different records are not by definition causally related to climate changes. Comparison of the different records on a common time-scale permits evaluation of the interrelationships and correlations to the Greenland ice-cores. Some events are the result of the complex interplay of different environmental variables and have no causal relationship with climate changes at all. By comparing the different records on a common time-scale and examining spatial patterns, the links between the proxies become evident.

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Interpolation methods for Antarctic ice-core timescales: application to Byrd, Siple Dome and Law Dome ice cores

Climate of the Past ◽

10.5194/cp-10-1195-2014 ◽

2014 ◽

Vol 10 (3) ◽

pp. 1195-1209 ◽

Cited By ~ 11

Author(s):

T. J. Fudge ◽

E. D. Waddington ◽

H. Conway ◽

J. M. D. Lundin ◽

K. Taylor

Keyword(s):

Accumulation Rate ◽

Ice Core ◽

Ice Cores ◽

Linear Interpolation ◽

Atmospheric Methane ◽

Interpolation Methods ◽

The Past ◽

Annual Layer ◽

Siple Dome ◽

Abrupt Changes

Abstract. Antarctic ice cores have often been dated by matching distinctive features of atmospheric methane to those detected in annually dated ice cores from Greenland. Establishing the timescale between these tie-point ages requires interpolation. While the uncertainty at tie points is relatively well described, uncertainty of the interpolation is not. Here we assess the accuracy of three interpolation schemes using data from the WAIS Divide ice core in West Antarctica; we compare the interpolation methods with the annually resolved timescale for the past 30 kyr. Linear interpolation yields large age errors (up to 380 years) between tie points, abrupt changes in duration of climate events at tie points, and an age bias. Interpolations based on the smoothest accumulation rate (ACCUM) or the smoothest annual-layer thickness (ALT) yield timescales that more closely agree with the annually resolved timescale and do not have abrupt changes in duration at tie points. We use ALT to assess the uncertainty in existing timescales for the past 30 kyr from Byrd, Siple Dome, and Law Dome. These ice-core timescales were developed with methods similar to linear interpolation. Maximum age differences exceed 1000 years for Byrd and Siple Dome, and 500 years for Law Dome. For the glacial–interglacial transition (21 to 12 kyr), the existing timescales are, on average, older than ALT by 40 years for Byrd, 240 years for Siple Dome, and 150 years for Law Dome. Because interpolation uncertainty is often not considered, age uncertainties for ice-core records are often underestimated.

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Indian monsoon and North Atlantic Oscillation signals reflected by Cl– and Na+ in a shallow ice core from Dasuopu glacier, Xixabangma, Himalaya

Annals of Glaciology ◽

10.3189/172756402781816825 ◽

2002 ◽

Vol 35 ◽

pp. 273-277 ◽

Cited By ~ 12

Author(s):

Wang Ninglian ◽

Yao Tandong ◽

Lonnie G. Thompson ◽

Mary E. Davis

Keyword(s):

North Atlantic Oscillation ◽

North Atlantic ◽

Chemical Constituents ◽

Ice Core ◽

Weight Ratio ◽

Ice Cores ◽

Northeast India ◽

High Positive Correlation ◽

The North ◽

Dasuopu Glacier

AbstractInformation about past atmospheric circulation and climate change can be revealed by the chemical constituents of ice cores. Based on the analytical results of Cl– and Na+ concentrations in an 18.5 m ice core, which contains 14 annual layers, from the Dasuopu glacier, central Himalaya, a significant correlation is found between Cl– and Na+ concentrations. This, along with the average Cl–/Na+ weight ratio of 1.9, indicates that moisture at the drilling site came mostly from oceans. Furthermore, there was a high positive correlation between the Cl–/Na+ ratio in the summer monsoon layers and the monsoon rainfall in northeast India, and there exists a teleconnection between the Cl– and Na+ concentrations in this shallow ice core and the North Atlantic Oscillation.

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Revisiting the absolute calibration of the Greenland ice-core age-scales

Climate of the Past Discussions ◽

10.5194/cpd-4-791-2008 ◽

2008 ◽

Vol 4 (3) ◽

pp. 791-807 ◽

Cited By ~ 2

Author(s):

L. Skinner

Keyword(s):

North Atlantic ◽

Ice Core ◽

Ice Cores ◽

Absolute Calibration ◽

North Atlantic Climate ◽

The Absolute ◽

Absolute Age ◽

Surface Reservoir ◽

Climate Events ◽

Age Constraints

Abstract. Recently, an absolute "calibration" was proposed for the GRIP and GISP2 Greenland ice-core time scales (Shackleton et al., 2004). This calibration attempted to reconcile the stratigraphic integration of ice-core, marine and speleothem archives with the absolute age constraints that marine and speleothem records incorporate. Here we revisit this calibration in light of the new layer-counted chronology of the NGRIP ice-core (GICC05). The GICC05 age-scale differs from the proposed absolute calibration by up to 1200 years late in the last glaciation, with implications both for radiocarbon cycling and the inferred timing of North Atlantic climate events relative to absolutely dated archives (e.g. relative sea-level). By precisely aligning the stratigraphy of Iberian Margin marine cores with that of the Greenland ice-cores, it appears that either: 1) the radiocarbon content of mid-latitude Atlantic surface-waters was extremely depleted (resulting in average surface reservoir ages up to 1700 years prior to ~22 ka BP); or 2) the GICC05 age-scale includes too few years (is up to 1200 years too young). It is shown here that both of these possibilities are in fact correct to some degree. Northeast Atlantic surface reservoir ages should be revised upward by ~350 years, while the NGRIP age-scale appears to be "missing" time. These findings illustrate the importance of integrated stratigraphy as a test for our chronologies, which are rarely truly "absolute". This is an important point, since probably the worst error that we can make is to entrench and generalise a precise stratigraphical relationship on the basis of erroneous absolute age assignations.

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Concurrent Changepoints in Greenland Ice Core δ18O records and the North Atlantic Oscillation over the Past Millennium

Atmosphere ◽

10.3390/atmos13010093 ◽

2022 ◽

Vol 13 (1) ◽

pp. 93

Author(s):

István Gábor Hatvani ◽

Dániel Topál ◽

Eric Ruggieri ◽

Zoltán Kern

Keyword(s):

North Atlantic Oscillation ◽

North Atlantic ◽

Structural Changes ◽

Ice Core ◽

Greenland Ice Sheet ◽

The Past ◽

The North ◽

The North Atlantic ◽

The North Atlantic Oscillation ◽

Past Millennium

Structural changes, or changepoints, coinciding in multiple ice core records over the Greenland Ice Sheet (GrIS) may reflect a widespread response of the GrIS to atmospheric forcing. Thus, to better understand how atmospheric circulation may regulate sudden changes in δ18O of Greenland precipitation, we seek synchronous changepoints occurring in ice core-derived δ18O time series across the GrIS and in the North Atlantic Oscillation (NAO) over the past millennium. By utilizing a Bayesian changepoint detection method, four changepoint horizons were revealed: at the beginning of the 20th century, in the late-15th century, and around the turn of the 11th and 10th centuries. Although the changepoints in ice core δ18O records exhibited distinctive spatial arrangements in each horizon, all corresponded to changepoints in the NAO, indicative of a consistent atmospheric influence on GrIS surface changes over the past millennium.

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Interpolation methods for Antarctic ice-core timescales: application to Byrd, Siple Dome and Law Dome ice cores

Climate of the Past Discussions ◽

10.5194/cpd-10-65-2014 ◽

2014 ◽

Vol 10 (1) ◽

pp. 65-104 ◽

Cited By ~ 1

Author(s):

T. J. Fudge ◽

E. D. Waddington ◽

H. Conway ◽

J. M. D. Lundin ◽

K. Taylor

Keyword(s):

Accumulation Rate ◽

Ice Core ◽

Ice Cores ◽

Linear Interpolation ◽

Atmospheric Methane ◽

Interpolation Methods ◽

The Past ◽

Annual Layer ◽

Siple Dome ◽

Abrupt Changes

Abstract. Antarctic ice cores have often been dated by matching distinctive features of atmospheric methane to those detected in annually dated ice cores from Greenland. Establishing the timescale between these tie-point ages requires interpolation. While the uncertainty at tie points is relatively well described, uncertainty of the interpolation is not. Here we assess the accuracy of three interpolation schemes using data from the WAIS Divide ice core in West Antarctica; we compare the interpolation methods with the annually resolved timescale for the past 30 kyr. Linear interpolation yields large age errors (up to 380 yr) between tie points, abrupt changes in duration at tie points, and an age bias. Interpolation based on the smoothest accumulation rate (ACCUM) or the smoothest annual-layer thickness (ALT) yield timescales that more closely agree with the annually resolved timescale and do not have abrupt changes in duration at the tie points. We use ALT to assess the uncertainty in existing timescales for the past 30 kyr from Byrd, Siple Dome, and Law Dome. These ice-core timescales were developed with methods similar to linear interpolation. Maximum age differences exceed 1000 yr for Byrd and Siple Dome, and 500 yr for Law Dome. For the glacial-interglacial transition (21 to 12 kyr), the existing timescales are, on average, older than ALT by 40 yr for Byrd, 240 yr for Siple Dome, and 150 yr for Law Dome. Because interpolation uncertainty is often not considered, age uncertainties for ice-core records are often underestimated.

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Aromatic acids in an Arctic ice core from Svalbard: a proxy record of biomass burning

Climate of the Past ◽

10.5194/cp-14-637-2018 ◽

2018 ◽

Vol 14 (5) ◽

pp. 637-651 ◽

Cited By ~ 8

Author(s):

Mackenzie M. Grieman ◽

Murat Aydin ◽

Elisabeth Isaksson ◽

Margit Schwikowski ◽

Eric S. Saltzman

Keyword(s):

North Atlantic ◽

Vanillic Acid ◽

Ice Core ◽

Ice Cores ◽

Hydroxybenzoic Acid ◽

Aromatic Acids ◽

Back Trajectories ◽

The North ◽

Negative State ◽

Arctic Ice

Abstract. This study presents vanillic acid and para-hydroxybenzoic acid levels in an Arctic ice core from Lomonosovfonna, Svalbard covering the past 800 years. These aromatic acids are likely derived from lignin combustion in wildfires and long-range aerosol transport. Vanillic and para-hydroxybenzoic acid are present throughout the ice core, confirming that these compounds are preserved on millennial timescales. Vanillic and para-hydroxybenzoic acid concentrations in the Lomonosovfonna ice core ranged from below the limits of detection to 0.2 and 0.07 ppb, respectively (1 ppb  =  1000 ng L−1). Vanillic acid levels are high (maximum of 0.1 ppb) from 1200 to 1400 CE, then gradually decline into the twentieth century. The largest peak in the vanillic acid in the record occurs from 2000 to 2008 CE. In the para-hydrobenzoic acid record, there are three centennial-scale peaks around 1300, 1550, and 1650 CE superimposed on a long-term decline in the baseline levels throughout the record. Ten-day air mass back trajectories for a decade of fire seasons (March–November, 2006–2015) indicate that Siberia and Europe are the principle modern source regions for wildfire emissions reaching the Lomonosovfonna site. The Lomonosovfonna data are similar to those from the Eurasian Arctic Akademii Nauk ice core during the early part of the record (1220–1400 CE), but the two ice cores diverge markedly after 1400 CE. This coincides with a shift in North Atlantic climate marked by a change of the North Atlantic Oscillation from a positive to a more negative state.

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