scholarly journals Visual observations and stratigraphy of the South Pole Ice Core (SPICEcore) : a preliminary Holocene (~10.2 ka) accumulation record and depth-age chronology

2019 ◽  
Author(s):  
John Fegyveresi ◽  
Tyler Fudge ◽  
David Ferris ◽  
Dominic Winski ◽  
Richard Alley
Keyword(s):  
Ice Core ◽  
South Pole ◽  
The South ◽  
Visual Observations

scholarly journals Modeling ice birefringence and oblique radio wave propagation for neutrino detection at the South Pole

2020 ◽  
Vol 61 (81) ◽  
pp. 84-91 ◽  
Author(s):  
T. M. Jordan ◽  
D. Z. Besson ◽  
I. Kravchenko ◽  
U. Latif ◽  
B. Madison ◽  
...  
Keyword(s):  
Time Delays ◽  
Ice Core ◽  
High Energy ◽  
Propagation Model ◽  
Neutrino Interaction ◽  
Crystallographic Axis ◽  
South Pole ◽  
The South ◽  
Range Estimation ◽  
Ice Flow

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.

scholarly journals δD And δ18O In South Pole Snow: Further Comparison With Meteorological Data and The Record From the Last Millennium (Abstract)

1988 ◽  
Vol 11 ◽  
pp. 208
Author(s):  
J. R. Petit ◽  
J. Jouzel ◽  
J. C. White ◽  
Qian Qiu-yu ◽  
M. Legrand ◽  
...  
Keyword(s):  
Seasonal Variation ◽  
Water Cycle ◽  
Meteorological Data ◽  
Ice Core ◽  
Snow Accumulation ◽  
South Pole ◽  
The South ◽  
Isotope Record ◽  
Δd And Δ18o ◽  
Isotope Content

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.

Supplementary material to "Advection (non-climate) impact on the South Pole Ice Core"

2019 ◽  
Author(s):  
Tyler J. Fudge ◽  
David A. Lilien ◽  
Michelle Koutnik ◽  
Howard Conway ◽  
C. Max Stevens ◽  
...  
Keyword(s):  
Ice Core ◽  
Climate Impact ◽  
South Pole ◽  
The South ◽  
Supplementary Material

The South Pole ice core (SPICEcore) project

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

scholarly journals Drilling operations for the South Pole Ice Core (SPICEcore) project

2020 ◽  
pp. 1-14 ◽  
Author(s):  
Jay A. Johnson ◽  
Tanner Kuhl ◽  
Grant Boeckmann ◽  
Chris Gibson ◽  
Joshua Jetson ◽  
...  
Keyword(s):  
Ice Core ◽  
Austral Summer ◽  
South Pole ◽  
The South ◽  
University Of Wisconsin ◽  
Drilling Operations ◽  
And Performance ◽  
Core Project ◽  
The University ◽  
Drill System

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.

Isotopes of molecular nitrogen, oxygen, and argon in the South Pole ice core document local and global climate change through the last deglaciation.

2021 ◽  
Author(s):  
Jacob Morgan ◽  
Christo Buizert ◽  
Jeff Severinghaus
Keyword(s):  
Global Climate ◽  
Molecular Nitrogen ◽  
Ice Core ◽  
South Pole ◽  
Last Deglaciation ◽  
The South ◽  
Temperature Changes ◽  
Temperature Proxy ◽  
Local Surface Temperature ◽  
First Time

<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>

scholarly journals A 200 year sulfate record from 16 Antarctic ice cores and associations with Southern Ocean sea-ice extent

2005 ◽  
Vol 41 ◽  
pp. 155-166 ◽  
Author(s):  
Daniel Dixon ◽  
Paul A. Mayewski ◽  
Susan Kaspari ◽  
Karl Kreutz ◽  
Gordon Hamilton ◽  
...  
Keyword(s):  
Sea Ice ◽  
Ross Sea ◽  
Ice Core ◽  
Ice Cores ◽  
South Pole ◽  
West Antarctica ◽  
The South ◽  
Sea Ice Extent ◽  
West Antarctic ◽  
Low Latitudes

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).

scholarly journals Cloud Cover over the South Pole from Visual Observations, Satellite Retrievals, and Surface-Based Infrared Radiation Measurements

2007 ◽  
Vol 20 (3) ◽  
pp. 544-559 ◽  
Author(s):  
Michael S. Town ◽  
Von P. Walden ◽  
Stephen G. Warren
Keyword(s):  
Radiative Forcing ◽  
Cloud Cover ◽  
Longwave Radiation ◽  
South Pole ◽  
The South ◽  
Cloud Properties ◽  
Satellite Retrievals ◽  
Polar Day ◽  
Very High ◽  
Visual Observations

Abstract Estimates of cloud cover over the South Pole are presented from five different data sources: routine visual observations (1957–2004; Cvis), surface-based spectral infrared (IR) data (2001; CPAERI), surface-based broadband IR data (1994–2003; Cpyr), the Extended Advanced Very High Resolution Radiometer (AVHRR) Polar Pathfinder (APP-x) dataset (1994–99; CAPP-x), and the International Satellite Cloud Climatology Project (ISCCP) dataset (1994–2003; CISCCP). The seasonal cycle of cloud cover is found to range from 45%–50% during the short summer to a relatively constant 55%–65% during the winter. Relationships between Cpyr and 2-m temperature, 10-m wind speed and direction, and longwave radiation are investigated. It is shown that clouds warm the surface in all seasons, 0.5–1 K during summer and 3–4 K during winter. The annual longwave cloud radiative forcing is 18 W m−2 for downwelling radiation and 10 W m−2 for net radiation. The cloud cover datasets are intercompared during the time periods in which they overlap. The nighttime bias of Cvis is worse than previously suspected, by approximately −20%; CISCCP shows some skill during the polar day, while CAPP-x shows some skill at night. The polar cloud masks for the satellite data reviewed here are not yet accurate enough to reliably derive surface or cloud properties over the East Antarctic Plateau. The best surface-based source of cloud cover in terms of the combination of accuracy and length of record is determined to be Cpyr. The use of the Cpyr dataset for further tests of satellite retrievals and for tests of polar models is recommended.

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 ◽  
South Pole ◽  
The South

scholarly journals Spectral and Broadband Longwave Downwelling Radiative Fluxes, Cloud Radiative Forcing, and Fractional Cloud Cover over the South Pole

2005 ◽  
Vol 18 (20) ◽  
pp. 4235-4252 ◽  
Author(s):  
Michael S. Town ◽  
Von P. Walden ◽  
Stephen G. Warren
Keyword(s):  
Water Vapor ◽  
Radiative Forcing ◽  
Cloud Cover ◽  
South Pole ◽  
The South ◽  
Near Surface ◽  
Cloud Radiative Forcing ◽  
Clear Sky ◽  
Fractional Cloud ◽  
Visual Observations

Abstract Annual cycles of downwelling broadband infrared radiative flux and spectral downwelling infrared flux were determined using data collected at the South Pole during 2001. Clear-sky conditions are identified by comparing radiance ratios of observed and simulated spectra. Clear-sky fluxes are in the range of 110–125 W m−2 during summer (December–January) and 60–80 W m−2 during winter (April–September). The variability is due to day-to-day variations in temperature, strength of the surface-based temperature inversion, atmospheric humidity, and the presence of “diamond dust” (near-surface ice crystals). The persistent presence of diamond dust under clear skies during the winter is evident in monthly averages of clear-sky radiance. About two-thirds of the clear-sky flux is due to water vapor, and one-third is due to CO2, both in summer and winter. The seasonal constancy of this approximately 2:1 ratio is investigated through radiative transfer modeling. Precipitable water vapor (PWV) amounts were calculated to investigate the H2O/CO2 flux ratio. Monthly mean PWV during 2001 varied from 1.6 mm during summer to 0.4 mm during winter. Earlier published estimates of PWV at the South Pole are similar for winter, but are 50% lower for summer. Possible reasons for low earlier estimates of summertime PWV are that they are based either on inaccurate hygristor technology or on an invalid assumption that the humidity was limited by saturation with respect to ice. The average fractional cloud cover derived from the spectral infrared data is consistent with visual observations in summer. However, the wintertime average is 0.3–0.5 greater than that obtained from visual observations. The annual mean of longwave downwelling cloud radiative forcing (LDCRF) for 2001 is about 23 W m−2 with no apparent seasonal cycle. This is about half that of the global mean LDCRF; the low value is attributed to the small optical depths and low temperatures of Antarctic clouds.

Sign in / Sign up

Export Citation Format

Share Document