Volcanic synchronisation between the EPICA Dome C and Vostok ice cores (Antarctica) 0–145 kyr BP

Abstract. This study aims at refining the synchronisation between the EPICA Dome C (EDC) and Vostok ice cores in the time interval 0–145 kyr BP by using the volcanic signatures. 111 common volcanic events were identified by using continuous electrical conductivity (ECM), di-electrical profiling (DEP) and sulfate measurements while trying to minimize the distortion of the glaciological chronologies. This is an update and a continuation of previous works performed over the 0–45 kyr interval which provided 56 tie points to the ice core chronologies (Udisti et al., 2004). This synchronisation will serve for the establishment of the next synchronised Antarctic dating. A change of slope in the EDC-depth/Vostok-depth diagram is probably related to a change of accumulation regime as well as to a change of ice thickness upstream of the Vostok lake, but we did not invoke any significant temporal change of surface accumulation at EDC relative to Vostok. A significant phase difference is detected between the EDC and Vostok isotopic records during the 95–120 kyr interval, but not during Termination II. Three possible candidates for the Toba volcanic super-eruption ~73 kyr ago are suggested in the Vostok and EDC volcanic records. However the ECM, DEP and sulfate fingerprints for these three events are not significantly larger than many others in the records.

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Volcanic synchronisation between the EPICA Dome C and Vostok ice cores (Antarctica) 0–145 kyr BP

Climate of the Past ◽

10.5194/cp-8-1031-2012 ◽

2012 ◽

Vol 8 (3) ◽

pp. 1031-1045 ◽

Cited By ~ 35

Author(s):

F. Parrenin ◽

J.-R. Petit ◽

V. Masson-Delmotte ◽

E. Wolff ◽

I. Basile-Doelsch ◽

...

Keyword(s):

Electrical Conductivity ◽

Phase Difference ◽

Temporal Change ◽

Ice Core ◽

Ice Cores ◽

Ice Thickness ◽

Time Interval ◽

Lake Vostok ◽

Volcanic Events ◽

Isotopic Records

Abstract. This study aims at refining the synchronisation between the EPICA Dome C (EDC) and Vostok ice cores in the time interval 0–145 kyr BP by using the volcanic signatures. 102 common volcanic events were identified by using continuous electrical conductivity (ECM), di-electrical profiling (DEP) and sulfate measurements while trying to minimize the distortion of the glaciological chronologies. This is an update and a continuation of previous works performed over the 0–45 kyr interval that provided 56 tie points to the ice core chronologies (Udisti et al., 2004). This synchronisation will serve to establish Antarctic Ice Core Chronology 2012, the next synchronised Antarctic dating. A change of slope in the EDC-depth/Vostok-depth diagram is probably related to a change of accumulation regime as well as to a change of ice thickness upstream of the Lake Vostok, but we did not invoke any significant temporal change of surface accumulation at EDC relative to Vostok. No significant phase difference is detected between the EDC and Vostok isotopic records, but depth shifts between the Vostok 3G and 5G ice cores prevent from looking at this problem accurately. Three possible candidates for the Toba volcanic super-eruption ~73 kyr ago are suggested in the Vostok and EDC volcanic records. Neither the ECM, DEP nor the sulfate fingerprints for these 3 events are significantly larger than many others in the records.

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An independently dated 2000-yr volcanic record from Law Dome, East Antarctica, including a new perspective on the dating of the c. 1450s eruption of Kuwae, Vanuatu

Climate of the Past Discussions ◽

10.5194/cpd-8-1567-2012 ◽

2012 ◽

Vol 8 (3) ◽

pp. 1567-1590 ◽

Cited By ~ 10

Author(s):

C. T. Plummer ◽

M. A. J. Curran ◽

T. D. van Ommen ◽

S. O. Rasmussen ◽

A. D. Moy ◽

...

Keyword(s):

Climate Models ◽

Ice Core ◽

Ice Cores ◽

Volcanic Eruptions ◽

East Antarctica ◽

External Information ◽

Time Interval ◽

Climatic Effects ◽

High Accumulation ◽

Volcanic Events

Abstract. Volcanic eruptions are an important cause of natural climate variability. In order to improve the accuracy of climate models, precise dating and magnitude of the climatic effects of past volcanism are necessary. Here we present a 2000-yr record of Southern Hemisphere volcanism recorded in ice cores from the high accumulation Law Dome site, East Antarctica. The ice cores were analyzed for a suite of chemistry signals and are independently dated via annual layer counting, with 11 ambiguous years by the end of the record. Independently dated records are important to avoid circular dating where volcanic signatures are assigned a date from some external information rather than using the date it is found in the ice core. Forty-five volcanic events have been identified using the sulfate chemistry of the Law Dome record. Comparisons between Law Dome and NGRIP (Greenland) volcanic records suggest Law Dome is the most accurately dated Antarctic volcanic dataset and allows for the records to be synchronized with NGRIP, leading to an improved global volcanic forcing dataset. Volcanic sulfate deposition estimates are important for modeling the climatic response to eruptions. The largest volcanic sulfate events in our record are dated at 1458 CE (Kuwae, Vanuatu), 1257 and 423 CE (unidentified). Using our record we refine the dating of previously known volcanic events and present evidence for two separate eruptions during the period 1450–1460 CE, potentially causing confusion in the assignment of the Kuwae (Vanuatu) eruption to volcanic signatures during this time interval.

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Tephra in the Greenland Ice cores: Insights into Icelandic volcano-climate impacts

10.5194/egusphere-egu21-9187 ◽

2021 ◽

Author(s):

Imogen Gabriel ◽

Gill Plunkett ◽

Peter Abbott ◽

Bergrún Óladóttir ◽

Joseph McConnell ◽

...

Keyword(s):

High Resolution ◽

Ice Core ◽

Ice Cores ◽

Volcanic Eruptions ◽

Climate Impacts ◽

Geochemical Analysis ◽

Volcanic Events ◽

Societal Impacts ◽

The Impact ◽

Ice Core Records

Volcanic eruptions are considered as one of the primary natural drivers for changes in the global climate system and understanding the impact of past eruptions on the climate is integral to adopt appropriate responses towards future volcanic eruptions.The Greenland ice core records are dominated by Icelandic eruptions, with several volcanic systems (Katla, Hekla, B&#225;r&#240;arbunga-Vei&#240;iv&#246;tn and Grimsv&#246;tn) being highly active throughout the Holocene. A notable period of increased Icelandic volcanic activity occurred between 500-1250 AD and coincided with climatic changes in the North Atlantic region which may have facilitated the Viking settlement of Greenland and Iceland. However, a number of these volcanic events are poorly constrained (duration and magnitude). Consequently, the Greenland ice cores offer the opportunity to reliably reconstruct past Icelandic volcanism (duration, magnitude and frequency) due to their high-resolution, the proximity of Iceland to Greenland and subsequent increased likelihood of volcanic fallout deposits (tephra particles and sulphur aerosols) being preserved. However, both the high frequency of eruptions between 500-1250 AD and the geochemical similarity of Iceland&#8217;s volcanic centres present challenges in making the required robust geochemical correlations between the source volcano and the ice core records and ultimately reliably assessing the climatic-societal impacts of these eruptions.To address this, we use two Greenland ice core records (TUNU2013 and B19) and undertake geochemical analysis on tephra from the volcanic events in the selected time window which have been detected and sampled using novel techniques (insoluble particle peaks and sulphur acidity peaks). Further geochemical analysis of proximal material enables robust correlations to be made between the events in the ice core records and their volcanic centres. The high-resolution of these polar archives provides a precise age for the event and when utilised alongside other proxies (i.e. sulphur aerosols), both the duration and magnitude of these eruptions can be constrained, and the climatic-societal impacts of these eruptions reliably assessed.

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Characterizing the glaciological conditions at Halvfarryggen ice dome, Dronning Maud Land, Antarctica

Journal of Glaciology ◽

10.3189/2013jog12j134 ◽

2013 ◽

Vol 59 (213) ◽

pp. 9-20 ◽

Cited By ~ 27

Author(s):

Reinhard Drews ◽

Carlos Martín ◽

Daniel Steinhage ◽

Olaf Eisen

Keyword(s):

Flow Model ◽

Ice Core ◽

Ice Cores ◽

Radar Data ◽

Ice Thickness ◽

Atmospheric Conditions ◽

Ice Flow ◽

International Partnerships ◽

Drill Site ◽

Dronning Maud Land

AbstractWe present a comprehensive approach (including field data, remote sensing and an anisotropic ice-flow model) to characterize Halvfarryggen ice dome in coastal Dronning Maud Land, Antarctica. This is a potential drill site for the International Partnerships in Ice Core Sciences, which has identified the need for ice cores covering atmospheric conditions during the last few millennia. We derive the surface topography, the ice stratigraphy from radar data, and accumulation rates which vary from 400 to 1670 kg m−2 a−1 due to preferred wind directions and changing surface slope. The stratigraphy shows anticlines and synclines beneath the divides. We transfer Dansgaard–Johnsen age–depth scales from the flanks along isochrones to the divide in the upper 20–50% of the ice thickness and show that they compare well with the results of a full-Stokes, anisotropic ice-flow model which predicts (1) 11 ka BP ice at 90% of the ice thickness, (2) a temporally stable divide for at least 2700–4500 years, (3) basal temperatures below the melting point (−12°C to −5°C) and (4) a highly developed crystal orientation fabric (COF). We suggest drilling into the apices of the deep anticlines, providing a good compromise between record length and temporal resolution and also facilitating studies of the interplay of anisotropic COF and ice flow.

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A 200 year sub-annual record of sulfate in West Antarctica, from 16 ice cores

Annals of Glaciology ◽

10.3189/172756404781814113 ◽

2004 ◽

Vol 39 ◽

pp. 545-556 ◽

Cited By ~ 34

Author(s):

Daniel Dixon ◽

Paul A. Mayewski ◽

Susan Kaspari ◽

Sharon Sneed ◽

Mike Handley

Keyword(s):

Ice Core ◽

Temporal Distribution ◽

Ice Cores ◽

Volcanic Eruptions ◽

Global Scale ◽

West Antarctica ◽

West Antarctic ◽

Volcanic Events ◽

Climate Transition ◽

Better Than

AbstractSixteen high-resolution ice-core records from West Antarctica and South Pole are used to examine the spatial and temporal distribution of sulfate for the last 200 years. The preservation of seasonal layers throughout the length of each record results in a dating accuracy of better than 1 year based on known global-scale volcanic events. A dual transport source for West Antarctic sea-salt (ss) SO42– and excess (xs) SO42– is observed: lower-tropospheric for areas below 1000m elevation and mid-/upper-tropospheric/stratospheric for areas located above 1000 m. Our xsSO42– records with volcanic peaks removed do not display any evidence of an anthropogenic impact on West Antarctic SO42– concentrations but do reveal that a major climate transition takes place over West Antarctica at ∼1940. Global-scale volcanic eruptions appear as significant peaks in the robust-spline residual xsSO42– records from sites located above 1000m elevation but do not appear in the residual records from sites located below 1000 m.

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The Recurrence Time of Dansgaard–Oeschger Events and Limits on the Possible Periodic Component

Journal of Climate ◽

10.1175/jcli3437.1 ◽

2005 ◽

Vol 18 (14) ◽

pp. 2594-2603 ◽

Cited By ~ 75

Author(s):

Peter D. Ditlevsen ◽

Mikkel S. Kristensen ◽

Katrine K. Andersen

Keyword(s):

Waiting Times ◽

Ice Core ◽

Ice Cores ◽

Recurrence Time ◽

Objective Criterion ◽

Climate Signal ◽

The North ◽

Climate Shifts ◽

Isotopic Records ◽

Core Project

Abstract By comparing the high-resolution isotopic records from the Greenland Ice Core Project (GRIP) and the North Greenland Ice Core Project (NGRIP) ice cores, the common climate signal in the records has been approximately separated from local noise. From this, an objective criterion for defining Dansgaard–Oeschger (DO) events is achieved. The analysis identifies several additional short-lasting events, increasing the total number of DO events to 27 in the period 12–90 kyr before present (BP). The quasi-regular occurrence of the DO events could indicate a stochastic or coherent resonance mechanism governing their origin. From the distribution of waiting times, a statistical upper bound on the strength of a possible periodic forcing is obtained. This finding indicates that the climate shifts are purely noise driven with no underlying periodicity.

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New insights into the ~74 ka Toba eruption from sulfur isotopes of polar ice cores

10.5194/egusphere-egu21-6495 ◽

2021 ◽

Author(s):

Laura Crick ◽

Andrea Burke ◽

William Hutchison ◽

Stephen Sparks ◽

Sue Mahony ◽

...

Keyword(s):

Inductively Coupled Plasma ◽

Sulfur Isotopes ◽

Ice Core ◽

Isotopic Fractionation ◽

Ice Cores ◽

Photochemical Reactions ◽

Quaternary Period ◽

Inductively Coupled ◽

Precise Timing ◽

Volcanic Events

The ~74ka Toba eruption in Indonesia was one of the largest volcanic events of the Quaternary and loaded an estimated 100 million tonnes of H2SO4 into the atmosphere. Understanding the precise timing of this colossal eruption is vital to unravelling the climatic and environmental impacts of the largest volcanic events on Earth. Sulfur aerosols injected into the stratosphere following large volcanic events scatter incoming radiation and lead to global cooling, and in the case of Toba it has been suggested that it led to cooling of 1 &#8211; 5&#176;C and extinctions of some local hominin populations. One of the most enigmatic features of the Toba eruption is that the S peak has yet to be identified in the ice core records, although numerous candidate sulfate peaks have been identified in both Arctic and Antarctic ice cores. To address this, we analysed the sulfur isotope fingerprint (&#948;34S and &#916;33S) of 11 Toba candidates from two Antarctic ice cores by multi-collector inductively coupled plasma mass spectrometry. This approach allows us to evaluate injection altitudes and to distinguish large tropical eruptions from proximal eruptions because stratospheric sulfur aerosols undergo UV photochemical reactions that impart a sulfur mass-independent isotopic fractionation (S-MIF). In contrast, tropospheric sulfur aerosols do not exhibit S-MIF because they are shielded from the relevant UV radiation by the ozone layer.We identify three stratospheric, tropical eruption candidates with two recording the largest &#916;33S signals measured to date in the ice core archives. The largest of these &#916;33S signals is >2 &#8240; more negative than previous measurements of the 1257 Samalas eruption (the largest eruption of the last 2000 years), despite having a similar integrated sulfate flux for this event to the ice core. These three candidates are within uncertainly of the Ar40/Ar39 age estimates for the Toba eruption and when considered with other paleoclimate proxies place the event during the transition into Greenland Stadial 20. &#160;Finally, we further analyse the relationship between the Toba eruption candidates and these proxies to determine the precise timing and potential climatic impacts of one of the largest eruptions of the Quaternary period.

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Variability of sulfate signal in ice core records based on five replicate cores

Climate of the Past ◽

10.5194/cp-12-103-2016 ◽

2016 ◽

Vol 12 (1) ◽

pp. 103-113 ◽

Cited By ~ 19

Author(s):

E. Gautier ◽

J. Savarino ◽

J. Erbland ◽

A. Lanciki ◽

P. Possenti

Keyword(s):

Ice Core ◽

Ice Cores ◽

Flux Measurement ◽

Volcanic Eruptions ◽

Local Scale ◽

High Temporal Resolution ◽

Polar Regions ◽

Regional Patterns ◽

Snow Drift ◽

Volcanic Events

Abstract. Current volcanic reconstructions based on ice core analysis have significantly improved over the past few decades by incorporating multiple-core analyses with a high temporal resolution from different parts of the polar regions into a composite common volcanic eruption record. Regional patterns of volcanic deposition are based on composite records, built from cores taken at both poles. However, in many cases only a single record at a given site is used for these reconstructions. This assumes that transport and regional meteorological patterns are the only source of the dispersion of the volcanic products. Here we evaluate the local-scale variability of a sulfate profile in a low-accumulation site (Dome C, Antarctica), in order to assess the representativeness of one core for such a reconstruction. We evaluate the variability with depth, statistical occurrence, and sulfate flux deposition variability of volcanic eruptions detected in five ice cores, drilled 1 m apart from each other. Local-scale variability, essentially attributed to snow drift and surface roughness at Dome C, can lead to a non-exhaustive record of volcanic events when a single core is used as the site reference, with a bulk probability of 30 % of missing volcanic events and close to 65 % uncertainty on one volcanic flux measurement (based on the standard deviation obtained from a five-core comparison). Averaging n records reduces the uncertainty of the deposited flux mean significantly (by a factor 1∕ √ n); in the case of five cores, the uncertainty of the mean flux can therefore be reduced to 29 %.

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Ice-core dating and chemistry by direct-current electrical conductivity

Journal of Glaciology ◽

10.3189/s0022143000002215 ◽

1992 ◽

Vol 38 (130) ◽

pp. 325-332 ◽

Cited By ~ 4

Author(s):

Kenorick Taylor ◽

Richard Alley ◽

Joe Fiacco ◽

Pieter Grootes ◽

Gregg Lamorey ◽

...

Keyword(s):

Electrical Conductivity ◽

Ice Core ◽

Low Frequency ◽

Ice Cores ◽

Quantitative Comparison ◽

Quantitative Interpretation ◽

Conductivity Measurements ◽

Temperature Variations ◽

The Core ◽

Ice Core Dating

AbstractAlthough quantitative interpretation of the low-frequency electrical conductivity of ice cores from central Greenland is complicated by temperature variations of the measured core, annual layers can be recognized in sections of the core that are not impacted by non-seasonal features. Ambiguities in counting of annual layers can be minimized by comparing the electrical conductivity measurements to measurements of dust concentration and visual stratigraphy. A non-linear relationship between applied voltage and the current measured across two electrodes complicates the quantitative comparison of measurements made with different equipment, but does not affect the overall shape of the observed features.

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Holocene Climate Variability in Antarctica Based on 11 Ice-Core Isotopic Records

Quaternary Research ◽

10.1006/qres.2000.2172 ◽

2000 ◽

Vol 54 (3) ◽

pp. 348-358 ◽

Cited By ~ 239

Author(s):

Valérie Masson ◽

Françoise Vimeux ◽

Jean Jouzel ◽

Vin Morgan ◽

Marc Delmotte ◽

...

Keyword(s):

Time Trend ◽

Ross Sea ◽

Ice Core ◽

Ice Cores ◽

West Antarctica ◽

Climatic Fluctuations ◽

Long Time ◽

Long Term Trends ◽

Isotopic Records

A comparison is made of the Holocene records obtained from water isotope measurements along 11 ice cores from coastal and central sites in east Antarctica (Vostok, Dome B, Plateau Remote, Komsomolskaia, Dome C, Taylor Dome, Dominion Range, D47, KM105, and Law Dome) and west Antarctica (Byrd), with temporal resolution from 20 to 50 yr. The long-term trends possibly reflect local ice sheet elevation fluctuations superimposed on common climatic fluctuations. All the records confirm the widespread Antarctic early Holocene optimum between 11,500 and 9000 yr; in the Ross Sea sector, a secondary optimum is identified between 7000 and 5000 yr, whereas all eastern Antarctic sites show a late optimum between 6000 and 3000 yr. Superimposed on the long time trend, all the records exhibit 9 aperiodic millennial-scale oscillations. Climatic optima show a reduced pacing between warm events (typically 800 yr), whereas cooler periods are associated with less-frequent warm events (pacing >1200 yr).

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