scholarly journals Volcanic synchronisation of the EPICA-DC and TALDICE ice cores for the last 42 kyr BP

2012 ◽  
Vol 8 (2) ◽  
pp. 509-517 ◽  
Author(s):  
M. Severi ◽  
R. Udisti ◽  
S. Becagli ◽  
B. Stenni ◽  
R. Traversi
Keyword(s):  
Ice Core ◽  
Ice Cores ◽  
New Age ◽  
Direct Transfer ◽  
Time Duration ◽  
Volcanic Events ◽  
Temporal Intervals ◽  
Apparent Duration ◽  
The Last Two Millennia ◽  
Rigorous Method

Abstract. The age scale synchronisation between the Talos Dome and the EPICA Dome C ice cores was carried on through the identification of several common volcanic signatures. This paper describes the rigorous method, using the signature of volcanic sulphate, which was employed for the last 42 kyr of the record. Using this tight stratigraphic link, we transferred the EDC age scale to the Talos Dome ice core, producing a new age scale for the last 12 kyr. We estimated the discrepancies between the modelled TALDICE-1 age scale and the new scale during the studied period, by evaluating the ratio R of the apparent duration of temporal intervals between pairs of isochrones. Except for a very few cases, R ranges between 0.8 and 1.2, corresponding to an uncertainty of up to 20% in the estimate of the time duration in at least one of the two ice cores. At this stage our approach does not allow us to unequivocally identify which of the models is affected by errors, but, taking into account only the historically known volcanic events, we found that discrepancies up to 200 yr appear in the last two millennia in the TALDICE-1 model, while our new age scale shows a much better agreement with the volcanic absolute horizons. Thus, we propose for the Talos Dome ice core a new age scale (covering the whole Holocene) obtained by a direct transfer, via our stratigraphic link, from the EDC modelled age scale by Lemieux-Dudon et al. (2010).

scholarly journals Volcanic synchronisation of the EPICA-DC and TALDICE ice cores for the last 42 kyr BP

2011 ◽  
Vol 7 (5) ◽  
pp. 3719-3743 ◽  
Author(s):  
M. Severi ◽  
R. Udisti ◽  
S. Becagli ◽  
B. Stenni ◽  
R. Traversi
Keyword(s):  
Ice Core ◽  
Ice Cores ◽  
New Age ◽  
Direct Transfer ◽  
Time Duration ◽  
Volcanic Events ◽  
Temporal Intervals ◽  
Apparent Duration ◽  
The Last Two Millennia ◽  
Rigorous Method

Abstract. The age scale synchronisation between the Talos Dome and the EPICA Dome C ice cores was carried on through the identification of several common volcanic signatures. This paper describes the rigorous method, using the signature of volcanic sulphate, which was employed for the last 42 kyr of the record. Using this tight stratigraphic link we transferred the EDC age scale to the Talos Dome ice core producing a new age scale for the last 42 kyr. We estimated the discrepancies between the modeled TALDICE-1 age scale and the new one during the studied period, by evaluating the ratio R of the apparent duration of temporal intervals between pairs of isochrones. Except for a very few cases, R ranges between 0.8 and 1.2 corresponding to an uncertainty of up to 20% in the estimate of the time duration in at least one of the two ice cores. At this stage our approach does not allow us unequivocally to find out which of the models is affected by errors, but, taking into account only the historically known volcanic events, we found that discrepancies up to 200 yr appears in the last two millennia in the TALDICE-1 model, while our new age scale shows a much better agreement with the volcanic absolute horizons. Thus, we propose for the Talos Dome ice core a new age scale (covering the whole Holocene) obtained by a direct transfer, via our stratigraphic link, from the EDC modelled age scale.

scholarly journals Synchronisation of the EDML and EDC ice cores for the last 52 kyr by volcanic signature matching

2007 ◽  
Vol 3 (2) ◽  
pp. 409-433 ◽  
Author(s):  
M. Severi ◽  
S. Becagli ◽  
E. Castellano ◽  
A. Morganti ◽  
R. Traversi ◽  
...  
Keyword(s):  
Time Scale ◽  
Ice Core ◽  
Ice Cores ◽  
Time Duration ◽  
Ice Flow ◽  
Common Time ◽  
Temporal Intervals ◽  
Apparent Duration ◽  
Dronning Maud Land ◽  
The One

Abstract. A common time scale for the EPICA ice cores from Dome C (EDC) and Dronning Maud Land (EDML) was established. Since EDML core was not drilled on a dome, the development of the EDML1 time scale for the EPICA ice core drilled in Dronning Maud Land was carried on by creating a detailed stratigraphic link between this core and the one drilled at Dome C, dated by a simpler 1D ice-flow model. The synchronisation between the two ice cores was built via the identification of several common volcanic signatures. This paper describes the rigorous method, using the signature of volcanic sulfate, which was employed for the last 52 kyr of the record. By evaluating the ratio R of the apparent duration of temporal intervals between couples of isochrones, the depth comparison between the two cores was turned into an estimate of anomalies between the modelled EDC and EDML glaciological age models during the studied period. On average R ranges between 0.8 and 1.2 corresponding to an uncertainty within 20% in the estimate of the time duration in at least one of the two ice cores. Significant deviations of R up to 1.4–1.5 are observed between 18 and 28 kyr BP. At this step our approach is not able to unequivocally find out which of the models is affected by the errors, but assuming the thinning function at both sites and accumulation history at Dome C, which was drilled on a dome, as being correct, this anomaly can be ascribed to a complex spatial accumulation variability (which may be different at present day and in the past) and to upstream ice flow in the area of the EDML core.

scholarly journals Synchronisation of the EDML and EDC ice cores for the last 52 kyr by volcanic signature matching

2007 ◽  
Vol 3 (3) ◽  
pp. 367-374 ◽  
Author(s):  
M. Severi ◽  
S. Becagli ◽  
E. Castellano ◽  
A. Morganti ◽  
R. Traversi ◽  
...  
Keyword(s):  
Time Scale ◽  
Ice Core ◽  
Ice Cores ◽  
Time Duration ◽  
Common Time ◽  
Signature Matching ◽  
Temporal Intervals ◽  
Apparent Duration ◽  
Dronning Maud Land ◽  
Accumulation History

Abstract. A common time scale for the EPICA ice cores from Dome C (EDC) and Dronning Maud Land (EDML) has been established. Since the EDML core was not drilled on a dome, the development of the EDML1 time scale for the EPICA ice core drilled in Dronning Maud Land was based on the creation of a detailed stratigraphic link between EDML and EDC, which was dated by a simpler 1D ice-flow model. The synchronisation between the two EPICA ice cores was done through the identification of several common volcanic signatures. This paper describes the rigorous method, using the signature of volcanic sulfate, which was employed for the last 52 kyr of the record. We estimated the discrepancies between the modelled EDC and EDML glaciological age scales during the studied period, by evaluating the ratio R of the apparent duration of temporal intervals between pairs of isochrones. On average R ranges between 0.8 and 1.2 corresponding to an uncertainty of up to 20% in the estimate of the time duration in at least one of the two ice cores. Significant deviations of R up to 1.4–1.5 are observed between 18 and 28 kyr before present (BP), where present is defined as 1950. At this stage our approach does not allow us unequivocally to find out which of the models is affected by errors, but assuming that the thinning function at both sites and accumulation history at Dome C (which was drilled on a dome) are correct, this anomaly can be ascribed to a complex spatial accumulation variability (which may be different in the past compared to the present day) upstream of the EDML core.

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

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

<p>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.</p><p>The Greenland ice core records are dominated by Icelandic eruptions, with several volcanic systems (Katla, Hekla, Bárðarbunga-Veiðivötn and Grimsvötn) 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’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.</p><p>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.</p>

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

2004 ◽  
Vol 39 ◽  
pp. 545-556 ◽  
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.

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

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

<p>The ~74ka Toba eruption in Indonesia was one of the largest volcanic events of the Quaternary and loaded an estimated 100 million tonnes of H<sub>2</sub>SO<sub>4</sub> 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 – 5°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 (δ<sup>34</sup>S and Δ<sup>33</sup>S) 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.</p><p>We identify three stratospheric, tropical eruption candidates with two recording the largest Δ<sup>33</sup>S signals measured to date in the ice core archives. The largest of these Δ<sup>33</sup>S signals is >2 ‰ 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 Ar<sup>40</sup>/Ar<sup>39 </sup>age estimates for the Toba eruption and when considered with other paleoclimate proxies place the event during the transition into Greenland Stadial 20.  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.</p>

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

2011 ◽  
Vol 7 (6) ◽  
pp. 4105-4147 ◽  
Author(s):  
F. Parrenin ◽  
J.-R. Petit ◽  
V. Masson-Delmotte ◽  
I. Basile-Doelsch ◽  
J. Jouzel ◽  
...  
Keyword(s):  
Electrical Conductivity ◽  
Phase Difference ◽  
Temporal Change ◽  
Ice Core ◽  
Ice Cores ◽  
Ice Thickness ◽  
Time Interval ◽  
Significant Phase ◽  
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. 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.

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

2016 ◽  
Vol 12 (1) ◽  
pp. 103-113 ◽  
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 %.

scholarly journals Internal radio-echo layering at Vostok station, Antarctica, as an independent stratigraphie control on the ice-core record

1998 ◽  
Vol 27 ◽  
pp. 360-364 ◽  
Author(s):  
Martin J. Siegert ◽  
Richard Hodgkinst ◽  
Julian A. Dowdeswell
Keyword(s):  
Ice Core ◽  
Ice Sheet ◽  
Ice Cores ◽  
M Wave ◽  
Geometric Spreading ◽  
Volcanic Events ◽  
Radio Echo Sounding ◽  
Ice Core Record ◽  
Vostok Station ◽  
Station Site

Antarctic radio-echo sounding (RES) data at 60 MHz have been used to determine an independent stratigraphy for the ice core at Vostok station, based on internal radio-echo layering. A-scope RES data allow the amplitude of reflected electromagnetic (e/m) waves to be measured and, by accounting fur geometric spreading and absorption losses of the e/m wave, power reflection coefficients (PRCs) to be calculated. This information is compared with time-continuous Z-scope RES data in order to trace continuous e/m reflectors across the ice sheet. Internal ice-sheet horizons deeper than 800 m are caused by layers of ice that possess distinctly different dielectric properties (i.e. acidic layers) compared with ice above and/or below. Comparison of four PRC samples, located ~ 5 km from Vostok station, revealed five distinct internal reflections between 1000 and 2200 m. Z-scope data from directly over the Vostok station site show the same five prominent internal radio-echo layers. The depth-related radio-echo signals were then compared with chemical records from the Vostok ice core, including the H2SO4 signal, a major component of which is derived from volcanic events. From this procedure, internal radio-echo reflectors and Vostok ice-core acid measurements were correlated. Avery good match was made between Z-scope and ice-core data. However, vertical offsets observed between A-scope-derived RES layers and peaks in the chemical signal of up to 100 m are probably due to the general Inkling of the ice-sheet layering between the core site and the RES flight-line. We conclude that 60 MHz RES layering may be regarded as a stratigraphy independent of palaeoclimate, and may be used to correlate other deep Southern Hemisphere ice cores.

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

2012 ◽  
Vol 8 (6) ◽  
pp. 1929-1940 ◽  
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 ◽  
Climatic Effects ◽  
High Accumulation ◽  
Annual Layer ◽  
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 analysed for a suite of chemistry signals and are independently dated via annual layer counting, with 11 ambiguous years at 23 BCE, which has presently the lowest error of all published long Antarctic ice cores. 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 sulphate chemistry of the Law Dome record. The low dating error and comparison with the NGRIP (North Greenland Ice Core Project) volcanic records (on the GICC05 timescale) suggest Law Dome is the most accurately dated Antarctic volcanic dataset, which will improve the dating of individual volcanic events and potentially allow better correlation between ice core records, leading to improvements in global volcanic forcing datasets. One of the most important volcanic events of the last two millennia is the large 1450s CE event, usually assigned to the eruption of Kuwae, Vanuatu. In this study, we review the evidence surrounding the presently accepted date for this event, and make the case that two separate eruptions have caused confusion in the assignment of this event. Volcanic sulphate deposition estimates are important for modelling the climatic response to eruptions. The largest volcanic sulphate events in our record are dated at 1458 CE (Kuwae?, Vanuatu), 1257 and 422 CE (unidentified).

Sign in / Sign up

Export Citation Format

Share Document