scholarly journals Core handling, transportation and processing for the South Pole ice core (SPICEcore) project — ERRATUM

2021 ◽  
pp. 1-1
Author(s):  
Joseph M. Souney ◽  
Mark S. Twickler ◽  
Murat Aydin ◽  
Eric J. Steig ◽  
T. J. Fudge ◽  
...  
Keyword(s):  
Ice Core ◽  
2020 ◽  
Vol 61 (81) ◽  
pp. 84-91 ◽  
Author(s):  
T. M. Jordan ◽  
D. Z. Besson ◽  
I. Kravchenko ◽  
U. Latif ◽  
B. Madison ◽  
...  

AbstractThe Askaryan Radio Array (ARA) experiment at the South Pole is designed to detect high-energy neutrinos which, via in-ice interactions, produce coherent radiation at frequencies up to 1000 MHz. Characterization of ice birefringence, and its effect upon wave polarization, is proposed to enable range estimation to a neutrino interaction and hence aid in neutrino energy reconstruction. Using radio transmitter calibration sources, the ARA collaboration recently measured polarization-dependent time delay variations and reported significant time delays for trajectories perpendicular to ice flow, but not parallel. To explain these observations, and assess the capability for range estimation, we use fabric data from the SPICE ice core to model ice birefringence and construct a bounding radio propagation model that predicts polarization time delays. We compare the model with new data from December 2018 and demonstrate that the measurements are consistent with the prevailing horizontal crystallographic axis aligned near-perpendicular to ice flow. The study supports the notion that range estimation can be performed for near flow-perpendicular trajectories, although tighter constraints on fabric orientation are desirable for improving the accuracy of estimates.


1988 ◽  
Vol 11 ◽  
pp. 208
Author(s):  
J. R. Petit ◽  
J. Jouzel ◽  
J. C. White ◽  
Qian Qiu-yu ◽  
M. Legrand ◽  
...  

The stable-isotope content of precipitation (δD and δ18O) is governed by the successive fractionation processes which occur during the atmospheric water cycle. As a result there is, in polar areas, a well-obeyed and theoretically well-understood linear relationship between the mean istopic content of snow and its mean temperature of formation. This relationship is well documented on a spatial scale but poorly known for a given site on a temporal basis, the main reason being that relatively long-term and sufficiently detailed meteorological data are only available for a few polar sites. The South Pole appears to be a suitable place for such a study because: (i) snow accumulation is high enough (∼20 cm of snow per year), thus reducing the possibility that annual layers will be lost as a result of wind; (ii) seasonal variation in isotope content is still preserved in snow up to 50 years old; (iii) meteorological data are available from the time the station was opened in 1957. Our previous studies of surface and recently deposited snow at the South Pole were very encouraging in this respect; they have been extended with a two-fold purpose: (i) to test the geographical representativity of the isotope record by comparing results from various cores taken within a 10 km radius of the station. The cores are dated by various techniques, such as stratigraphy, seasonal variation in isotopic content, beta-radioactivity fall-out layers, and detection by solid conductivity measurements of the high “spike” which is thought to correspond to the 1815 Tambora eruption; (ii) to discuss the South Pole isotope record over the last 1000 years as recovered from a 127 m deep ice core.


2019 ◽  
Author(s):  
Tyler J. Fudge ◽  
David A. Lilien ◽  
Michelle Koutnik ◽  
Howard Conway ◽  
C. Max Stevens ◽  
...  

2019 ◽  
Author(s):  
Joseph Souney ◽  
Murat Aydin ◽  
Eric Steig ◽  
T. Fudge ◽  
Mark Twickler
Keyword(s):  
Ice Core ◽  

2020 ◽  
pp. 1-14 ◽  
Author(s):  
Jay A. Johnson ◽  
Tanner Kuhl ◽  
Grant Boeckmann ◽  
Chris Gibson ◽  
Joshua Jetson ◽  
...  

Abstract Over the course of the 2014/15 and 2015/16 austral summer seasons, the South Pole Ice Core project recovered a 1751 m deep ice core at the South Pole. This core provided a high-resolution record of paleoclimate conditions in East Antarctica during the Holocene and late Pleistocene. The drilling and core processing were completed using the new US Intermediate Depth Drill system, which was designed and built by the US Ice Drilling Program at the University of Wisconsin–Madison. In this paper, we present and discuss the setup, operation, and performance of the drill system.


2021 ◽  
Author(s):  
Jacob Morgan ◽  
Christo Buizert ◽  
Jeff Severinghaus

<p>Ice core gas records are an invaluable paleoclimatic archive. The three most abundant gases in air, nitrogen (N<sub>2</sub>), oxygen (O<sub>2</sub>), and argon (Ar), provide paleoclimatic information about both global and regional processes including tropical rainfall patterns and local surface temperature changes. We present a large dataset of elemental and isotopic ratios of N<sub>2</sub>, O<sub>2</sub>, and Ar (O<sub>2</sub>/N<sub>2</sub>, Ar/N<sub>2</sub>, δ<sup>15</sup>N, δ<sup>18</sup>O, & δ<sup>40</sup>Ar) from the South Pole Ice Core between 0 – 52,000 yr BP, with a focus on high precision δ<sup>15</sup>N and δ<sup>40</sup>Ar measurements between 5,000 – 32,000 yr BP. The unprecedented precision of our measurements allows us to use δ<sup>15</sup>N<sub>excess </sub>(= δ<sup>15</sup>N - δ<sup>40</sup>Ar/4) to reconstruct past temperature change at the South Pole. Although this proxy has been widely applied in Greenland, this is the first time it has been successfully applied to Antarctic ice and provides a valuable independent check on the more traditional water isotopes temperature proxy. We find good agreement between the two during the relatively stable climate of the glacial period and the Holocene. However the temperature reconstructions diverge during the deglaciation. We present several hypotheses that could explain the discrepancy and look to other emerging ice core temperature proxies to support our interpretation.</p>


2005 ◽  
Vol 41 ◽  
pp. 155-166 ◽  
Author(s):  
Daniel Dixon ◽  
Paul A. Mayewski ◽  
Susan Kaspari ◽  
Karl Kreutz ◽  
Gordon Hamilton ◽  
...  

AbstractChemistry data from 16, 50–115m deep, sub-annually dated ice cores are used to investigate spatial and temporal concentration variability of sea-salt (ss) SO42– and excess (xs) SO42– over West Antarctica and the South Pole for the last 200 years. Low-elevation ice-core sites in western West Antarctica contain higher concentrations of SO42– as a result of cyclogenesis over the Ross Ice Shelf and proximity to the Ross Sea Polynya. Linear correlation analysis of 15 West Antarctic ice-core SO42– time series demonstrates that at several sites concentrations of ssSO42– are higher when sea-ice extent (SIE) is greater, and the inverse for xsSO42–. Concentrations of xsSO42– from the South Pole site (East Antarctica) are associated with SIE from the Weddell region, and West Antarctic xsSO42– concentrations are associated with SIE from the Bellingshausen–Amundsen–Ross region. The only notable rise of the last 200 years in xsSO42–, around 1940, is not related to SIE fluctuations and is most likely a result of increased xsSO42– production in the mid–low latitudes and/or an increase in transport efficiency from the mid–low latitudes to central West Antarctica. These high-resolution records show that the source types and source areas of ssSO42– and xsSO42– delivered to eastern and western West Antarctica and the South Pole differ from site to site but can best be resolved using records from spatial ice-core arrays such as the International Trans-Antarctic Scientific Expedition (ITASE).


2019 ◽  
Vol 15 (5) ◽  
pp. 1793-1808 ◽  
Author(s):  
Dominic A. Winski ◽  
Tyler J. Fudge ◽  
David G. Ferris ◽  
Erich C. Osterberg ◽  
John M. Fegyveresi ◽  
...  

Abstract. The South Pole Ice Core (SPICEcore) was drilled in 2014–2016 to provide a detailed multi-proxy archive of paleoclimate conditions in East Antarctica during the Holocene and late Pleistocene. Interpretation of these records requires an accurate depth–age relationship. Here, we present the SPICEcore (SP19) timescale for the age of the ice of SPICEcore. SP19 is synchronized to the WD2014 chronology from the West Antarctic Ice Sheet Divide (WAIS Divide) ice core using stratigraphic matching of 251 volcanic events. These events indicate an age of 54 302±519 BP (years before 1950) at the bottom of SPICEcore. Annual layers identified in sodium and magnesium ions to 11 341 BP were used to interpolate between stratigraphic volcanic tie points, yielding an annually resolved chronology through the Holocene. Estimated timescale uncertainty during the Holocene is less than 18 years relative to WD2014, with the exception of the interval between 1800 to 3100 BP when uncertainty estimates reach ±25 years due to widely spaced volcanic tie points. Prior to the Holocene, uncertainties remain within 124 years relative to WD2014. Results show an average Holocene accumulation rate of 7.4 cm yr−1 (water equivalent). The time variability of accumulation rate is consistent with expectations for steady-state ice flow through the modern spatial pattern of accumulation rate. Time variations in nitrate concentration, nitrate seasonal amplitude and δ15N of N2 in turn are as expected for the accumulation rate variations. The highly variable yet well-constrained Holocene accumulation history at the site can help improve scientific understanding of deposition-sensitive climate proxies such as δ15N of N2 and photolyzed chemical compounds.


2019 ◽  
Author(s):  
Dominic A. Winski ◽  
Tyler J. Fudge ◽  
David G. Ferris ◽  
Erich C. Osterberg ◽  
John M. Fegyveresi ◽  
...  

Abstract. The South Pole Ice Core (SPICEcore) was drilled in 2014–2016 to provide a detailed multi-proxy archive of paleoclimate conditions in East Antarctica during the Holocene and late Pleistocene. Interpretation of these records requires an accurate depth-age relationship. Here, we present the SP19 timescale for the age of the ice of SPICEcore. SP19 is synchronized to the WD2014 chronology from the West Antarctic Ice Sheet Divide (WAIS Divide) ice core using stratigraphic matching of 251 volcanic events. These events indicate an age of 54 302 ± 519 years BP (before the year 1950) at the bottom of SPICEcore. Annual layers identified in sodium and magnesium ions to 11 341 BP were used to interpolate between stratigraphic volcanic tie points, yielding an annually-resolved chronology through the Holocene. Estimated timescale uncertainty during the Holocene is less than 18 years relative to WD2014, with the exception of the interval between 1800 to 3100 BP when uncertainty estimates reach ± 25 years due to widely spaced volcanic tie points. Prior to the Holocene, uncertainties remain within 124 years relative to WD2014. Results show an average Holocene accumulation rate of 7.4 cm/yr (water equivalent). The time variability of accumulation rate is consistent with expectations for steady-state ice flow through the modern spatial pattern of accumulation rate. Time variations in nitrate concentration, nitrate seasonal amplitude, and δ15N of N2 in turn are as expected for the accumulation-rate variations. The highly variable yet well-constrained Holocene accumulation history at the site can help improve scientific understanding of deposition-sensitive climate proxies such as δ15N of N2 and photolyzed chemical compounds.


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