Stable isotope records for the past 2000 years from four ice cores in central Dronning Maud Land, Antarctica

2012 ◽  
Vol 279-280 ◽  
pp. 357
Author(s):  
Hans Oerter
Keyword(s):  
Stable Isotope ◽  
Ice Cores ◽  
The Past ◽  
Past 2000 Years ◽  
Dronning Maud Land

scholarly journals Fire in ice: two millennia of Northern Hemisphere fire history from the Greenland NEEM ice core

2014 ◽  
Vol 10 (1) ◽  
pp. 809-857 ◽  
Author(s):  
P. Zennaro ◽  
N. Kehrwald ◽  
J. R. McConnell ◽  
S. Schüpbach ◽  
O. Maselli ◽  
...  
Keyword(s):  
Black Carbon ◽  
Biomass Burning ◽  
Fire History ◽  
Global Climate ◽  
Ice Cores ◽  
Dominant Factor ◽  
The Past ◽  
Past 2000 Years ◽  
Isotopic Analyses ◽  
Fire Activity

Abstract. Biomass burning is a major source of greenhouse gases and influences regional to global climate. Pre-industrial fire-history records from black carbon, charcoal and other proxies provide baseline estimates of biomass burning at local to global scales, but there remains a need for broad-scale fire proxies that span millennia in order to understand the role of fire in the carbon cycle and climate system. We use the specific biomarker levoglucosan, and multi-source black carbon and ammonium concentrations to reconstruct fire activity from the North Greenland Eemian (NEEM) ice cores (77.49° N; 51.2° W, 2480 m a.s.l.) over the past 2000 years. Increases in boreal fire activity (1000–1300 CE and 1500–1700 CE) over multi-decadal timescales coincide with the most extensive central and northern Asian droughts of the past two millennia. The NEEM biomass burning tracers coincide with temperature changes throughout much of the past 2000 years except for during the extreme droughts, when precipitation changes are the dominant factor. Many of these multi-annual droughts are caused by monsoon failures, thus suggesting a connection between low and high latitude climate processes. North America is a primary source of biomass burning aerosols due to its relative proximity to the NEEM camp. During major fire events, however, isotopic analyses of dust, back-trajectories and links with levoglucosan peaks and regional drought reconstructions suggest that Siberia is also an important source of pyrogenic aerosols to Greenland.

scholarly journals Characteristics of ice rises and ice rumples in Dronning Maud Land and Enderby Land, Antarctica

2020 ◽  
Vol 66 (260) ◽  
pp. 1064-1078
Author(s):  
Vikram Goel ◽  
Kenichi Matsuoka ◽  
Cesar Deschamps Berger ◽  
Ian Lee ◽  
Jørgen Dall ◽  
...  
Keyword(s):  
Mass Balance ◽  
Ice Cores ◽  
Ice Thickness ◽  
Ice Shelf ◽  
Ice Dynamics ◽  
Surface Mass ◽  
Ice Shelves ◽  
The Past ◽  
Dronning Maud Land ◽  
The Antarctic

AbstractIce rises and rumples, locally grounded features adjacent to ice shelves, are relatively small yet play significant roles in Antarctic ice dynamics. Their roles generally depend upon their location within the ice shelf and the stage of the ice-sheet retreat or advance. Large, long-stable ice rises can be excellent sites for deep ice coring and paleoclimate study of the Antarctic coast and the Southern Ocean, while small ice rises tend to respond more promptly and can be used to reveal recent changes in regional mass balance. The coasts of Dronning Maud Land (DML) and Enderby Land in East Antarctica are abundant with these features. Here we review existing knowledge, presenting an up-to-date status of research in these regions with focus on ice rises and rumples. We use regional datasets (satellite imagery, surface mass balance and ice thickness) to analyze the extent and surface morphology of ice shelves and characteristic timescales of ice rises. We find that large parts of DML have been changing over the past several millennia. Based on our findings, we highlight ice rises suitable for drilling ice cores for paleoclimate studies as well as ice rises suitable for deciphering ice dynamics and evolution in the region.

scholarly journals High resolution climate reconstructions of recent warming using instrumental and ice core records from coastal Antarctica

MAUSAM ◽  
2021 ◽  
Vol 62 (4) ◽  
pp. 665-672
Author(s):  
MELOTH THAMBAN ◽  
SUSHANT S.NAIK ◽  
C.M. LALURAJ ◽  
R. RAVINDRA
Keyword(s):  
Climate Change ◽  
High Resolution ◽  
Southern Oscillation ◽  
Ice Core ◽  
Ice Cores ◽  
Temporal Consistency ◽  
The Past ◽  
Proxy Records ◽  
Dronning Maud Land ◽  
Land Region

In-situ observational record of Antarctic surface temperatures is rather sparse. Proxy based ice core studies are thus critical for reconstructing the past climate change on centennial and decadal time scales. The present study review the available instrumental and proxy records from the Dronning Maud Land region of East Antarctica as well as report recent evidences of Antarctic climate change and its global linkages. The monthly mean air temperature records of the Novolazarevskaya (Novo) station, which is the longest (since 1961) and continuous meteorological record in this region, revealed a significant warming trend at a rate of 0.25 °C / decade. To understand the spatial and temporal consistency of this warming, well-dated ice cores from the coastal Dronning Maud Land region were assessed. All proxy records consistently suggest an enhanced warming up to +0.12 °C / decade. This is further supported by a recent assessment of stable oxygen and hydrogen isotope proxy records from two high resolution ice cores (IND-25/B5 and IND-22/B4) from this region. Among these records, the IND-25/B5 provided ultra-high-resolution data for the past 100 years (1905-2005) and the IND-22/B4 core represented the past ~470 years (1530-2002) of Antarctic change. These ice records provided insights on the influence of solar forcing on Antarctic climate system as well as its linkages with the tropical and mid-latitude climatic modes like the Southern Annular Mode (SAM) and El Niño Southern Oscillation (ENSO). The calculated surface air temperatures using these records showed a warming by 0.06-0.1 °C / decade, with greatly enhanced warming during the past several decades (~0.4 °C / decade). It is confirmed that the coastal areas of Dronning Maud Land are indeed warming and the trend is apparently enhancing in the recent decades.

Compiling a chemistry database from Antarctic ice cores records spanning the past 2000 years

2021 ◽  
Author(s):  
Diana Vladimirova ◽  
Elizabeth Thomas ◽  
on behalf of CLIVASH2k
Keyword(s):  
Sea Ice ◽  
Atmospheric Circulation ◽  
Large Scale ◽  
Ice Cores ◽  
Snow Accumulation ◽  
Sea Ice Extent ◽  
Large Variability ◽  
The Past ◽  
Direct Observations ◽  
Past 2000 Years

<p>Trends in sea ice extent and atmospheric circulation around Antarctica have exhibited large variability over recent decades. Direct observations such as satellite data cover the past four decades only. Thus, a comparison with paleoclimate archives is essential to understand the natural and anthropogenic components of these recent changes. We have initiated a data call within CLIVASH2k community (http://pastglobalchanges.org/science/wg/2k-network/projects/clivash) to collect all available sodium (Na+) and sulfate (SO42-) concentration and fluxes from Antarctic ice cores. We aim to improve our understanding of large-scale sea-ice variability and atmospheric circulation over the past 2000 years. In this respect, ice cores are a unique archive.</p><p>Here we present the new database, which builds on previous efforts by the PAGES community in gathering snow accumulation (Thomas et al. 2017) and stable water isotope data (Stenni et al. 2017).  To date, 88 published and 14 unpublished records have been submitted, 10 of which span the full 2000 years. The data, especially 2000 years-long records are equally distributed over the Antarctic continent and all coastal regions are well represented.  The new data will allow us to investigate interannual and decadal-to-centennial scale variability in sea ice extent and atmospheric circulation and its regional differences over the past 2000 years.</p>

scholarly journals Firn accumulation records for the past 1000 years on the basis of dielectric profiling of six cores from Dronning Maud Land, Antarctica

2004 ◽  
Vol 50 (169) ◽  
pp. 279-291 ◽  
Author(s):  
Coen M. Hofstede ◽  
S.W van de Wal Roderik ◽  
Karsten A. Kaspers ◽  
Michiel R. van den Broeke ◽  
Lars Karlöf ◽  
...  
Keyword(s):  
20Th Century ◽  
Accumulation Rate ◽  
Ice Cores ◽  
Snow Accumulation ◽  
The Past ◽  
Medium Length ◽  
Dronning Maud Land ◽  
The Mean ◽  
Firn Core ◽  
Past 1000 Years

AbstractThis paper presents an overview of firn accumulation in Dronning Maud Land (DML), Antarctica, over the past 1000 years. It is based on a chronology established with dated volcanogenic horizons detected by dielectric profiling of six medium-length firn cores. In 1998 the British Antarctic Survey retrieved a medium-length firn core from western DML. During the Nordic EPICA (European Project for Ice Coring in Antarctica) traverse of 2000/01, a 160 m long firn core was drilled in eastern DML. Together with previously published data from four other medium-length ice cores from the area, these cores yield 50 possible volcanogenic horizons. All six firn cores cover a mutual time record until the 29th eruption. This overlapping period represents a period of approximately 1000 years, with mean values ranging between 43 and 71 mm w.e. The cores revealed no significant trend in snow accumulation. Running averages over 50 years, averaged over the six cores, indicate temporal variations of5%. All cores display evidence of a minimum in the mean annual firn accumulation rate around AD 1500 and maxima around AD 1400 and 1800. The mean increase over the early 20th century was the strongest increase, but the absolute accumulation rate was not much higher than around AD 1400. In eastern DML a 13% increase is observed for the second half of the 20th century.

scholarly journals The EPICA ice core from Dronning Maud Land: first results from stable-isotope measurements

2004 ◽  
Vol 39 ◽  
pp. 307-312 ◽  
Author(s):  
Hans Oerter ◽  
Wolfgang Graf ◽  
Hanno Meyer ◽  
Frank Wilhelms
Keyword(s):  
Stable Isotope ◽  
Diffusion Processes ◽  
Ice Core ◽  
Ice Cores ◽  
Deuterium Excess ◽  
Near Surface ◽  
Core Section ◽  
First Results ◽  
Low Pass ◽  
Dronning Maud Land

AbstractThe European Project for Ice Coring in Antarctica (EPICA) focuses on the drilling of two deep ice cores, the first at Dome C and the second at Kohnen station (75°00’ S, 0°04’ E) in Dronning Maud Land (DML). This paper deals with stable-isotope records from ice cores drilled in DML. In the first season, the deep EPICA DML core reached a depth of 450 m, recovering ice approximately 7000 years old. Generally, the δ18O record indicates a stable Holocene climate and shows low variability. However, during the last 4000 years (based on a preliminary time-scale) the δ18O values decrease continuously by about 0.6%, and the deuterium excess values increase by about 0.5%. The correlation between δ18O and the deuterium excess d is investigated for a 50m long core section and the near-surface snow. High-pass filtered profiles are positively correlated, whereas the correlation between low-pass filtered profiles is negative. A post-depositional effect due to diffusion processes can be seen in a sub-annually resolved profile from snow-pit samples. Changes in the seasonality of the evolution of the snow cover and the consequences for stable-isotope content are demonstrated with data from ice core B31.

scholarly journals Antarctic Sea Ice Proxies from Marine and Ice Core Archives Suitable for Reconstructing Sea Ice over the Past 2000 Years

Geosciences ◽  
2019 ◽  
Vol 9 (12) ◽  
pp. 506 ◽  
Author(s):  
Elizabeth R. Thomas ◽  
Claire S. Allen ◽  
Johan Etourneau ◽  
Amy C. F. King ◽  
Mirko Severi ◽  
...  
Keyword(s):  
Sea Ice ◽  
20Th Century ◽  
Climate Models ◽  
Ross Sea ◽  
Ice Core ◽  
Ice Cores ◽  
Weddell Sea ◽  
The Past ◽  
Antarctic Sea Ice ◽  
Past 2000 Years

Dramatic changes in sea ice have been observed in both poles in recent decades. However, the observational period for sea ice is short, and the climate models tasked with predicting future change in sea ice struggle to capture the current Antarctic trends. Paleoclimate archives, from marine sedimentary records and coastal Antarctic ice cores, provide a means of understanding sea ice variability and its drivers over decadal to centennial timescales. In this study, we collate published records of Antarctic sea ice over the past 2000 years (2 ka). We evaluate the current proxies and explore the potential of combining marine and ice core records to produce multi-archive reconstructions. Despite identifying 92 sea ice reconstructions, the spatial and temporal resolution is only sufficient to reconstruct circum-Antarctic sea ice during the 20th century, not the full 2 ka. Our synthesis reveals a 90 year trend of increasing sea ice in the Ross Sea and declining sea ice in the Bellingshausen, comparable with observed trends since 1979. Reconstructions in the Weddell Sea, the Western Pacific and the Indian Ocean reveal small negative trends in sea ice during the 20th century (1900–1990), in contrast to the observed sea ice expansion in these regions since 1979.

10 Be and δ 2 H in polar ice cores as a probe of the solar variability’s influence on climate

1990 ◽  
Vol 330 (1615) ◽  
pp. 463-470 ◽  
Keyword(s):  
Mass Spectrometry ◽  
Stable Isotope ◽  
Ice Core ◽  
Ice Cores ◽  
Cosmic Ray ◽  
Galactic Cosmic Rays ◽  
South Pole ◽  
Polar Ice ◽  
Temperature Dependent ◽  
The Past

By using the technique of accelerator mass spectrometry, it is now possible to measure detailed profiles of cosmogenic (cosmic ray produced) 10 Be in polar ice cores. Recent work has demonstrated that these profiles contain information on solar activity, via its influence on the intensity of galactic cosmic rays arriving in the Earth’s atmosphere. It has been known for some time that, as a result of temperature-dependent fractionation effects, the stable isotope profiles δ 2 O and δ 2 H in polar ice cores contain palaeoclimate information. Thus by comparing the 10 Be and stable isotope profiles in the same ice core, one can test the influence of solar variability on climate, and this independent of possible uncertainties in the absolute chronology of the records. We present here the results of such a comparison for two Antarctic ice cores; one from the South Pole, covering the past ca . 1000 years, and one from Dome C, covering the past ca . 3000 years.

scholarly journals Glacio-chemical study spanning the past 2 kyr on three ice cores from Dronning Maud Land, Antarctica: 1. Annually resolved accumulation rates

2000 ◽  
Vol 105 (D24) ◽  
pp. 29411-29421 ◽  
Author(s):  
S. Sommer ◽  
C. Appenzeller ◽  
R. Röthlisberger ◽  
M. A. Hutterli ◽  
B. Stauffer ◽  
...  
Keyword(s):  
Ice Cores ◽  
Chemical Study ◽  
Accumulation Rates ◽  
The Past ◽  
Dronning Maud Land
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