scholarly journals An ice-core-based, Late Holocene history for the Transantarctic Mountains, Antarctica

1995 ◽  
pp. 33-45 ◽  
Author(s):  
P. A. Mayewski ◽  
W. B. Lyons ◽  
G. Zielinski ◽  
M. Twickler ◽  
S. Whitlow ◽  
...  
Keyword(s):  
Late Holocene ◽  
Ice Core ◽  
Transantarctic Mountains

scholarly journals An Ice-Core-Based, Late Holocene History for the Transantarctic Mountains, Antarctica

2013 ◽  
pp. 33-45
Author(s):  
P. A. Mayewski ◽  
W. B. Lyons ◽  
G. Zielinski ◽  
M. Twickler ◽  
S. Whitlow ◽  
...  
Keyword(s):  
Late Holocene ◽  
Ice Core ◽  
Transantarctic Mountains

Climate related variations in atmospheric nitrous oxide concentration during the Mid- to Late Holocene

2021 ◽  
Author(s):  
Syed Azharuddin ◽  
Jinho Ahn ◽  
Yeongjun Ryu ◽  
Ed Brook
Keyword(s):  
Nitrous Oxide ◽  
Late Holocene ◽  
Ice Core ◽  
Progressive Increase ◽  
La Niña ◽  
La Nina ◽  
National University ◽  
Seoul National University ◽  
Sudden Decrease ◽  
Nitrous Oxide Concentration

<p>Nitrous oxide (N<sub>2</sub>O) is an important greenhouse gas with sources that respond to the biogeochemical processes on land and ocean. The major sources of atmospheric N<sub>2</sub>O are nitrification and denitrification occurring in terrestrial soils and the ocean. Here we present a new high-resolution atmospheric N<sub>2</sub>O record obtained from South Pole Ice (SPICE) core site covering the Mid- to Late Holocene (since ~5.5 ka). The N<sub>2</sub>O analysis was performed in a specialised wet extraction facility installed at Seoul National University that used small ice samples (<20 g) to yield a high precision (average standard deviation of ~1ppb) record. The new N<sub>2</sub>O data agree well with existing records on the millennial scale and reveal new details on the multi-centennial scale. Our results show a progressive increase in atmospheric N<sub>2</sub>O during 5.5 to 3.2 ka which correlates well with the increase of marine denitrification around the Arabian Sea (AS) and Peru-Chile Margin (PCM) as well as Indian monsoon precipitation around the same period. A local minimum in N<sub>2</sub>O is observed around 2.8 ka, possibly related to a sudden decrease in Western Tropical South (WTS) Pacific sea surface temperature and increased La-Nina like conditions which may have supressed denitrification along PCM. These conditions may have further influenced the monsoons and reduced denitrification in land soils. Our record also shows a local N<sub>2</sub>O maximum around 2.2 ka which may correspond to relaxed La-Nina like conditions around WTS Pacific. Subsequently, the N<sub>2</sub>O further dropped to attain a pronounced minimum around 1.4 ka. Similar N<sub>2</sub>O minima are also observed in Styx (Antarctica) and  NEEM (Greenland) ice core records, demonstrating the robustness of the signals.</p>

scholarly journals Holocene temperature variations inferred from Antarctic ice cores

1994 ◽  
Vol 20 ◽  
pp. 427-436 ◽  
Author(s):  
P. Ciais ◽  
J. Jouzel ◽  
J. R. Petit ◽  
V. Lipenkov ◽  
J. W. C. White
Keyword(s):  
Late Holocene ◽  
Ice Core ◽  
Ice Cores ◽  
Temperature Fluctuations ◽  
Base Line ◽  
Temperature Changes ◽  
Average Temperature ◽  
The Past ◽  
Reconstructed Temperature ◽  
Line Temperature

We have reconstructed temperature changes over the past 15 000 years from ice-core data in Antarctica. We used measurements of the D/H isotope ratio in ice as a proxy of temperature for central sites (Vostok, Dome C and Komsomolskaya; as well as coastal sites (D47, D15 and D10). First, we examined the dating of each core and built up a common temporal framework for the ensemble of the data. Secondly, we addressed the problem of inferring small-amplitude temperature fluctuations from the isotope data, in the light of noise-generating mechanisms involved in snow deposition. Temperature was reconstructed so as to minimize distortion created by the sampling of ice cores in the field. The seven ice cores studied yield an average temperature curve which can be put in perspective with nearby paleoclimatic records. The early Holocene experienced climates warmer than today by 1-2°C. The late Holocene period shows more discernible, shorter-duration, temperature fluctuations, superimposed on a fairly stable "base-line" temperature.

scholarly journals Late-Holocene climate evolution at the WAIS Divide site, West Antarctica: bubble number-density estimates

2011 ◽  
Vol 57 (204) ◽  
pp. 629-638 ◽  
Author(s):  
J.M. Fegyveresi ◽  
R.B. Alley ◽  
M.K. Spencer ◽  
J.J. Fitzpatrick ◽  
E.J. Steig ◽  
...  
Keyword(s):  
Late Holocene ◽  
Accumulation Rate ◽  
Ice Core ◽  
Temperature History ◽  
Flow Density ◽  
Number Density ◽  
West Antarctica ◽  
Surface Cooling ◽  
Bubble Number ◽  
Bubble Number Density

AbstractA surface cooling of ∼1.7°C occurred over the ∼two millennia prior to ∼1700 CE at the West Antarctic ice sheet (WAIS) Divide site, based on trends in observed bubble number-density of samples from the WDC06A ice core, and on an independently constructed accumulation-rate history using annual-layer dating corrected for density variations and thinning from ice flow. Density increase and grain growth in polar firn are both controlled by temperature and accumulation rate, and the integrated effects are recorded in the number-density of bubbles as the firn changes to ice. Number-density is conserved in bubbly ice following pore close-off, allowing reconstruction of either paleotemperature or paleo-accumulation rate if the other is known. A quantitative late-Holocene paleoclimate reconstruction is presented for West Antarctica using data obtained from the WAIS Divide WDC06A ice core and a steady-state bubble number-density model. The resultant temperature history agrees closely with independent reconstructions based on stable-isotopic ratios of ice. The ∼1.7°C cooling trend observed is consistent with a decrease in Antarctic summer duration from changing orbital obliquity, although it remains possible that elevation change at the site contributed part of the signal. Accumulation rate and temperature dropped together, broadly consistent with control by saturation vapor pressure.

Late Quaternary Eolian Deposition in Central Italy

2000 ◽  
Vol 54 (2) ◽  
pp. 246-252 ◽  
Author(s):  
Biancamaria Narcisi
Keyword(s):  
North Africa ◽  
Late Holocene ◽  
Late Quaternary ◽  
Ice Core ◽  
Central Italy ◽  
Last Interglacial ◽  
Central Mediterranean ◽  
Volcanic Lakes ◽  
Dust Loading ◽  
The Antarctic

Records of eolian quartz from two continuous sediment sequences drilled in Lagaccione and Lago di Vico volcanic lakes in central Italy contribute to the knowledge of eolian deposition in the central Mediterranean during the last 100,000 years. The chronology is based on 14C and 40Ar/39Ar dating and tephra analysis. Pollen data provide the paleoenvironmental framework and enable correlation between the cores. Eolian inputs were high during the steppe phases corresponding to oxygen isotope stages 4 and 2. Low inputs correspond to the forest phases of the last interglacial and the middle Holocene. Eolian inputs have increased in the late Holocene. Patterns of eolian deposition in central Italy resemble the Antarctic dust record from the Vostok ice core. The Italian patterns may also correspond with hydrological changes registered in North Africa. The main source of dust loading over the Mediterranean now, North Africa, may have played an important role in dust supply throughout the last climatic cycle.

Pollen Analysis of the 1973 Ice Core from Devon Island Glacier, Canada

1984 ◽  
Vol 22 (1) ◽  
pp. 68-76 ◽  
Author(s):  
John H. McAndrews
Keyword(s):  
Late Holocene ◽  
Ice Core ◽  
Ice Sheet ◽  
Early Holocene ◽  
The Arctic ◽  
Devon Island ◽  
Glacier Ice ◽  
Shrub Tundra ◽  
Low Arctic ◽  
Pollen And Spores

Meltwater from a 299-m-long ice core was filtered and analyzed for fossil pollen and spores. Pollen concentration was higher in the late Holocene and interglacial intervals (ca. 7 liter−1) than in the early Holocene and Wisconsinan (ca. 1–2 liter−1) ones. The late Holocene and interglacial assemblages were dominated by Alnus (alder), whereas the early Holocene and Wisconsinan ones were dominated by Betula (birch) and Artemisia (sage). During the Holocene and probably the last interglaciation, most of the pollen and spores were blown a minimum of 1000 km from low arctic shrub tundra and adjacent subarctic Picea (spruce) forest; these areas were dominated by the arctic air mass during the summer pollinating season. During the Wisconsinan-early Holocene, glacier ice and arctic air were more widespread and pollen sources were more distant; thus, at this time relatively little pollen was incorporated into the ice.The Devon ice-core data suggest that there should have been pollen in the continental ice sheet of Wisconsin time. When the ice sheet retreated this pollen would be carried by meltwater and redeposited with silt and clay together with contemporary pollen, producing an ecologically anomalous assemblage.

ABRUPT LATE HOLOCENE SHIFT IN ATMOSPHERIC CIRCULATION RECORDED BY MINERAL DUST IN THE SIPLE DOME ICE CORE, ANTARCTICA

2018 ◽  
Author(s):  
Bess Koffman ◽  
◽  
Steven L. Goldstein ◽  
Michael R. Kaplan ◽  
Gisela Winckler ◽  
...  
Keyword(s):  
Atmospheric Circulation ◽  
Late Holocene ◽  
Mineral Dust ◽  
Ice Core ◽  
Siple Dome

ABRUPT LATE HOLOCENE SHIFT IN ATMOSPHERIC CIRCULATION RECORDED BY MINERAL DUST IN THE SIPLE DOME ICE CORE, ANTARCTICA

2019 ◽  
Author(s):  
Bess Koffman ◽  
◽  
Steven L. Goldstein ◽  
Michael R. Kaplan ◽  
Gisela Winckler ◽  
...  
Keyword(s):  
Atmospheric Circulation ◽  
Late Holocene ◽  
Mineral Dust ◽  
Ice Core ◽  
Siple Dome
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