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TALDICE-1 age scale of the Talos Dome deep ice core, East Antarctica
D. Buiron, J. Chappellaz, B. Stenni, M. Frezzotti, M. Baumgartner, E. Capron, A. Landais, B. Lemieux-Dudon, V. Masson-Delmotte, M. Montagnat, F. Parrenin,A. Schilt
Climate of the Past (CP) & Discussions (CPD) , 2011,
Abstract: A new deep ice core drilling program, TALDICE, has been successfully handled by a European team at Talos Dome, in the Ross Sea sector of East Antarctica, down to 1620 m depth. Using stratigraphic markers and a new inverse method, we produce the first official chronology of the ice core, called TALDICE-1. We show that it notably improves an a priori chronology resulting from a one-dimensional ice flow model. It is in agreement with a posteriori controls of the resulting accumulation rate and thinning function along the core. An absolute uncertainty of only 300 yr is obtained over the course of the last deglaciation. This uncertainty remains lower than 600 yr over Marine Isotope Stage 3, back to 50 kyr BP. The phasing of the TALDICE ice core climate record with respect to the central East Antarctic plateau and Greenland records can thus be determined with a precision allowing for a discussion of the mechanisms at work at sub-millennial time scales.
TALDICE-1 age scale of the Talos Dome deep ice core, East Antarctica  [PDF]
D. Buiron,J. Chappellaz,B. Stenni,M. Frezzotti
Climate of the Past Discussions , 2010, DOI: 10.5194/cpd-6-1733-2010
Abstract: A new deep ice core drilling, TALDICE, has been successfully handled by a European team at Talos Dome, in the Ross Sea sector of East Antarctica, down to 1620 m depth. Using stratigraphic markers and a new inverse method, we produce the first official chronology of the ice core, called TALDICE-1. We show that it notably improves an a priori chronology resulting from a one-dimensional ice flow model, and that it is in agreement with a posteriori controls of the resulting accumulation rate and thinning function along the core. An absolute uncertainty of only 300 yr is obtained in the course of the last deglaciation. This uncertainty remains lower than 600 yr over Marine Isotope Stage 3, back to 50 kyr BP. The phasing of the TALDICE ice core climate record with respect to the central East Antarctic plateau and Greenland records can thus be determined with a precision allowing for a discussion of the mechanisms at work at sub-millennial time scales.
Location of a new ice core site at Talos Dome (East Antarctica)  [cached]
S. Urbini,L. Cafarella,A. Zirizzotti,C. Bianchi
Annals of Geophysics , 2006, DOI: 10.4401/ag-3104
Abstract: In the frame of glaciology and palaeoclimate research, Talos Dome (72°48lS; 159°06lE), an ice dome on the East Antarctic plateau, represents the new selected site for a new deep ice core drilling. The increasing interest in this region is due to the fact that the ice accumulation is higher here than in other domes in East Antarctica. A new deep drilling in this site could give important information about the climate changes near the coast. Previous papers showed that the dome summit is situated above a sloped bedrock. A new position on a relatively flat bedrock 5-6 km far from here in the SE direction was defined as a possible new ice core site for an European (Italy, France, Swiss and United Kingdom) drilling project named as TALDICE (TALos Dome Ice Core Project). This point, named as ID1 (159°11l00mE; 72°49l40mS), became the centre of the Radio Echo Sounding (RES) flight plan during the 2003 Italian Antarctic expedition, with the aim of confirming the new drilling site choice. In this paper 2001 and 2003 RES data sets have been used to draw a better resolution of ice thickness, bottom morphology and internal layering of a restricted area around the dome. Based on the final results, point ID1 has been confirmed as the new coring site. Finally, the preliminary operations about the installation of the summer ice core camp (TALDICE) at ID1 site carried out during the XX Italian Antarctic expedition (November 2004-December 2005) are briefly described.
Radio Echo Sounding (RES) investigations at Talos Dome (East Antarctica): bedrock topography and ice thickness  [cached]
C. Bianchi,L. Cafarella,P. De Michelis,A. Forieri
Annals of Geophysics , 2003, DOI: 10.4401/ag-3471
Abstract: Radio echo sounding measurements were collected during two Antarctic expeditions to determine the ice thickness and the sub-glacial morphology of Talos Dome in the region around 72°48'S; 159°06'E (about 6400 km2) on the edge of the East Antarctic plateau adjacent to Victoria Land in the western Ross Sea sector. The increasing interest in this region is due to the fact that in this area the ice accumulation is higher than in other sites in East Antarctica. Because of this, Talos Dome could be a new site for a project of a deep ice core drilling to obtain information on climate changes near the coast of Antarctica. In this frame, the knowledge of the bedrock topography is of great importance to choose the best location for the drilling site. In this paper, airborne radio echo sounding results from two Antarctic expeditions (1997 and 1999) are presented. Bedrock topography in bi- and three-dimensions for the Talos Dome region are discussed.
Interpreting last glacial to Holocene dust changes at Talos Dome (East Antarctica): implications for atmospheric variations from regional to hemispheric scales  [PDF]
S. Albani,B. Delmonte,V. Maggi,C. Baroni
Climate of the Past Discussions , 2012, DOI: 10.5194/cpd-8-145-2012
Abstract: Central East Antarctica ice cores preserve stratigraphic records of mineral dust originating from remote sources in the Southern Hemisphere, and represent useful indicators of climatic variations on glacial-interglacial time scales. The peripheries of the East Antarctic Ice Sheet, where ice-free areas with the potential to emit dust exist, have been less explored from this point of view. Here we present a new profile of dust deposition flux and grain size distributions from an ice core drilled at Talos Dome (Northern Victoria Land, East Antarctica), where there is a significant input of dust from proximal Antarctic ice-free areas. We analyze dust and stable water isotopes variations from the Last Glacial Maximum to the Late Holocene, and compare them to the EPICA Dome C profiles from Central East Antarctica. The smaller glacial-interglacial variations at Talos Dome compared to Dome C, and a distinctive decreasing trend during the Holocene, characterize the TALDICE dust profile. By deciphering the composite dust signal from both remote and local sources, we show the potential of this combined proxy of source activity and atmospheric transport to give information on both regional and larger spatial scales. In particular, we show how a regional signal, which we related to the deglaciation history of the Ross Sea embayment, can be superimposed to the broader scale glacial-interglacial variability that characterizes other Antarctic sites.
Interpreting last glacial to Holocene dust changes at Talos Dome (East Antarctica): implications for atmospheric variations from regional to hemispheric scales
S. Albani, B. Delmonte, V. Maggi, C. Baroni, J.-R. Petit, B. Stenni, C. Mazzola,M. Frezzotti
Climate of the Past (CP) & Discussions (CPD) , 2012,
Abstract: Central East Antarctic ice cores preserve stratigraphic records of mineral dust originating from remote sources in the Southern Hemisphere, and represent useful indicators of climatic variations on glacial-interglacial time scales. The peripheries of the East Antarctic Ice Sheet, where ice-free areas with the potential to emit dust exist, have been less explored from this point of view. Here, we present a new profile of dust deposition flux and grain size distributions from an ice core drilled at Talos Dome (TALDICE, Northern Victoria Land, East Antarctica), where there is a significant input of dust from proximal Antarctic ice-free areas. We analyze dust and stable water isotopes variations from the Last Glacial Maximum to the Late Holocene, and compare them to the EPICA Dome C profiles from central East Antarctica. The smaller glacial-interglacial variations at Talos Dome compared to Dome C and a distinctive decreasing trend during the Holocene characterize the TALDICE dust profile. By deciphering the composite dust signal from both remote and local sources, we show the potential of this combined proxy of source activity and atmospheric transport to give information on both regional and larger spatial scales. In particular, we show how a regional signal, which we relate to the deglaciation history of the Ross Sea embayment, can be superimposed to the broader scale glacial-interglacial variability that characterizes other Antarctic sites.
Sulphate and chloride aerosols during Holocene and last glacial periods preserved in the Talos Dome Ice Core, a peripheral region of Antarctica  [PDF]
Yoshinori Iizuka,Barbara Delmonte,Ikumi Oyabu,Torbj?RN Karlin
Tellus B , 2013, DOI: 10.3402/tellusb.v65i0.20197
Abstract: Antarctic ice cores preserve the record of past aerosols, an important proxy of past atmospheric chemistry. Here we present the aerosol compositions of sulphate and chloride particles in the Talos Dome (TD) ice core from the Holocene and Last Glacial Period. We find that the main salt types of both periods are NaCl, Na2SO4 and CaSO4, indicating that TD ice contains relatively abundant sea salt (NaCl) from marine primary particles. By evaluating the molar ratio of NaCl to Na2SO4, we show that about half of the sea salt does not undergo sulphatisation during late Holocene. Compared to in inland Antarctica, the lower sulphatisation rate at TD is probably due to relatively little contact between sea salt and sulphuric acid. This low contact rate can be related to a reduced time of reaction for marine-sourced aerosol before reaching TD and/or to a reduced post-depositional effect from the higher accumulation rate at TD. Many sulphate and chloride salts are adhered to silicate minerals. The ratio of sulphate-adhered mineral to particle mass and the corresponding ratio of chloride-adhered mineral both increase with increasing dust concentration. Also, the TD ice appears to contain Ca(NO3)2 or CaCO3 particles, thus differing from aerosol compositions in inland Antarctica, and indicating the proximity of peripheral regions to marine aerosols.
Volcanic synchronisation between the EPICA Dome C and Vostok ice cores (Antarctica) 0–145 kyr BP  [PDF]
F. Parrenin,J.-R. Petit,V. Masson-Delmotte,I. Basile-Doelsch
Climate of the Past Discussions , 2011, DOI: 10.5194/cpd-7-4105-2011
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.
Volcanic synchronisation between the EPICA Dome C and Vostok ice cores (Antarctica) 0–145 kyr BP
F. Parrenin, J.-R. Petit, V. Masson-Delmotte, E. Wolff, I. Basile-Doelsch, J. Jouzel, V. Lipenkov, S. O. Rasmussen, J. Schwander, M. Severi, R. Udisti, D. Veres,B. M. Vinther
Climate of the Past (CP) & Discussions (CPD) , 2012,
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.
Mineral and Sea-Salt Aerosol Fluxes over the Last 340 kyr Reconstructed from the Total Concentration of Al and Na in the Dome Fuji Ice Core  [PDF]
Hironori Sato, Toshitaka Suzuki, Motohiro Hirabayashi, Yoshinori Iizuka, Hideaki Motoyama, Yoshiyuki Fujii
Atmospheric and Climate Sciences (ACS) , 2013, DOI: 10.4236/acs.2013.32020
Abstract:

A quantitative analysis of the total concentrations of Al and Na in the Antarctic ice sheet during the past 340 kyr was performed by applying the acid digestion method to the Dome Fuji ice core. Atmospheric fluxes of mineral and sea-salt aerosol to Dome Fuji were calculated from the total concentration. The average fluxes of mineral aerosol to Dome Fuji in the periods of glacial maximum, 18.6 ± 10.1 mg·m2·yr–1, were larger than the value in the interglacial periods, 3.77 ± 2.20 mg·m–2·yr–1. Conversely, the fluxes of sea-salt have no significant difference between the average value of glacial maximum, 130 ± 55 mg·m–2·yr–1, and that of interglacial, 111 ± 54 mg·m–2·yr–1. The results obtained in this study suggest that the variation of mineral aerosol flux in Dome Fuji, together with climate change, was much larger than that of sea-salt aerosol flux. This result may have occurred because the variety in the intensity of the source and transport during the glacial-interglacial cycle is more significant for mineral aerosol than that for sea-salt aerosol.

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