scholarly journals A Refined Method to Analyze Insoluble Particulate Matter in Ice Cores, and Its Application to Diatom Sampling in the Antarctic Peninsula

2021 ◽  
Vol 9 ◽  
Author(s):  
Dieter Tetzner ◽  
Elizabeth R. Thomas ◽  
Claire S. Allen ◽  
Eric W. Wolff
Keyword(s):  
Particulate Matter ◽  
Antarctic Peninsula ◽  
Ice Cores ◽  
Particulate Material ◽  
New Method ◽  
Polycarbonate Membrane ◽  
Low Concentration ◽  
Annual Variations ◽  
Filtration System ◽  
The Antarctic

The insoluble particulate matter deposited on ice sheets provide key information to reconstruct past climate. The low concentration of some insoluble particulate matter, such as terrigenous particles and microfossils, challenges the efficiency of the recovery and the representativeness of the results. Here we present a new optimized method to extract, quantify and classify targeted low concentration insoluble particulate matter. Particle recovery rates and particle distribution were investigated using polystyrene particle standards filtered through Polycarbonate membrane filters and subsequently scanned in a scanning electron microscope. Experimental results in continuous and discrete sampling systems reveal consistent trends in the transport and removal of particulate material inside a filtration system. Statistical simulations are used to optimize the sample analyses required to achieve representative results. The analysis of diatoms in ice cores using this new method uncovered their potential to hold valuable climate records from the Antarctic Peninsula region. The data presented here evidence the presence of a measurable amount of marine diatoms with sub-annual variations, highlighting the potential of this record as a seasonal indicator. The new method presented provides an optimized and statistically representative approach for extracting, recovering and analyzing micrometre-sized, low-concentration insoluble particulate matter in ice.

scholarly journals Climate since AD 1510 on Dyer Plateau, Antarctic Peninsula: evidence for recent climate change

1994 ◽  
Vol 20 ◽  
pp. 420-426 ◽  
Author(s):  
L. G. Thompson ◽  
D. A. Peel ◽  
E. Mosley-thompson ◽  
R. Mulvaney ◽  
J. Dal ◽  
...  
Keyword(s):  
19Th Century ◽  
Antarctic Peninsula ◽  
Chemical Species ◽  
Ice Cores ◽  
Warming Trend ◽  
Snow Accumulation ◽  
Annual Variations ◽  
Recent Climate ◽  
The 19Th Century ◽  
The Antarctic

A 480 year record of the oxygen-isotope ratios, dust content, chemical species and net accumulation from ice cores drilled in 1989 90 on Dyer Plateau in the Antarctic Peninsula is presented. The continuous analyses of small (sub-annual) samples reveal well-preserved annual variations in both sulfate content and δ18O, thus allowing an excellent time-scale to be established.This history reveals a recent pronounced warming in which the last two decades have been among the warmest in the last five centuries. Furthermore, unlike in East Antarctica, on Dyer Plateau conditions appear to have been fairly normal from AD 1500 to 1850 with cooler conditions from 1850 to 1930 and a warming trend dominating since 1930. Reconstructed annual layer thicknesses suggest an increase in net accumulation beginning early in the 19th century and continuing to the present. This intuitive conflict between increasing net accumulation and depleted δ18O (cooler climate) in the 19th century appears widespread in the peninsula region and challenges our understanding of the physical relationships among moisture sources, air temperatures and snow accumulation. The complex meteorological regime in the Antarctic Peninsula region complicates meaningful interpretation of proxy indicators and results in a strong imprint of local high-frequency processes upon the larger-scale climate picture.

scholarly journals Climate since AD 1510 on Dyer Plateau, Antarctic Peninsula: evidence for recent climate change

1994 ◽  
Vol 20 ◽  
pp. 420-426 ◽  
Author(s):  
L. G. Thompson ◽  
D. A. Peel ◽  
E. Mosley-thompson ◽  
R. Mulvaney ◽  
J. Dal ◽  
...  
Keyword(s):  
19Th Century ◽  
Antarctic Peninsula ◽  
Chemical Species ◽  
Ice Cores ◽  
Warming Trend ◽  
Snow Accumulation ◽  
Annual Variations ◽  
Recent Climate ◽  
The 19Th Century ◽  
The Antarctic

A 480 year record of the oxygen-isotope ratios, dust content, chemical species and net accumulation from ice cores drilled in 1989 90 on Dyer Plateau in the Antarctic Peninsula is presented. The continuous analyses of small (sub-annual) samples reveal well-preserved annual variations in both sulfate content and δ18O, thus allowing an excellent time-scale to be established.This history reveals a recent pronounced warming in which the last two decades have been among the warmest in the last five centuries. Furthermore, unlike in East Antarctica, on Dyer Plateau conditions appear to have been fairly normal from AD 1500 to 1850 with cooler conditions from 1850 to 1930 and a warming trend dominating since 1930. Reconstructed annual layer thicknesses suggest an increase in net accumulation beginning early in the 19th century and continuing to the present. This intuitive conflict between increasing net accumulation and depleted δ18O (cooler climate) in the 19th century appears widespread in the peninsula region and challenges our understanding of the physical relationships among moisture sources, air temperatures and snow accumulation. The complex meteorological regime in the Antarctic Peninsula region complicates meaningful interpretation of proxy indicators and results in a strong imprint of local high-frequency processes upon the larger-scale climate picture.

Black Carbon deposition on snow from Antarctic Peninsula

2020 ◽  
Author(s):  
Francisco Cereceda-Balic ◽  
Maria Florencia Ruggeri ◽  
Victor Vidal ◽  
Humberto Gonzalez
Keyword(s):  
Black Carbon ◽  
Antarctic Peninsula ◽  
Radiative Forcing ◽  
Anthropogenic Activities ◽  
Thick Layer ◽  
The Andes ◽  
Filtration System ◽  
Antarctic Snow ◽  
The Antarctic ◽  
Snow Samples

<p>Atmospheric Black carbon (BC) strongly affects direct radiative forcing and climate, not only while suspended in the atmosphere but also after deposition onto high albedo surfaces, which are especially sensitive, because the absorption of solar radiation by deposited BC accelerate the snowpack/ice melting. In the Southern Hemisphere, the BC generated in the continents can be transported through the atmosphere from low and mid-latitudes to Antarctica, or it can be emitted in Antarctica by the anthropogenic activities developed in situ.  To assess the potential origin of the BC deposited in the snow of the Antarctic, and establish a possible relationship with the human activities that are carried out there, snow samples were taken in different sites from the Antarctic peninsula during summer periods: Chilean Base O’Higgins (BO), 2014; La Paloma Glacier 2015 and 2016 (at a distance of 6 km separated from BO); close to Chilean Base Yelcho (BY), 2018 and away from Chilean Base Yelcho 2018 (at a distance of 5 km separated from BY). Shallow snow samples were collected in Whirl-Pak (Nasco) plastics bags from the top of the snowpack, in an area of 1 m<sup>2</sup> and 5 cm thick layer, using a clean plastic shovel and disposable dust-free nitrile gloves. Sample weighed around 1500-2000 g, and they were kept always frozen (-20 °C), during transport and storage, until they could be processed in the laboratory. BC concentration in the snow samples was determined by using a novel methodology recently developed, published and patent by the authors (Cereceda et al 2019, https://doi.org/10.1016/j.scitotenv.2019.133934; US 16/690,013-Nov, 2019 ). The methodology consisted of a filter-based optical method where snow samples were microwave-assisted melted, then filtered through a special filtration system able to generate a uniform BC spot on Nuclepore 47 mm polycarbonate filters (Whatman, UK). BC deposited in filters was analyzed using a SootScan™, Model OT21 Optical Transmissometer (Magee Scientific, USA), where optical transmission was compared between the sample and a reference filter at a wavelength of 880 nm. The BC mass concentration was calculated using a 5-points calibration curve, previously prepared using real diesel BC soot as standard.  Results showed a BC concentration in snow of 1283.8 ± 1240 µg kg<sup>-1</sup>. Snow from O’Higgins Base presented the highest BC concentration (3395.7 µg kg<sup>-1</sup>), followed by snow from the site close to Yelcho Base (1309.2 µg kg<sup>-1</sup>), snow from La Paloma Glacier 2016 (745.9 µg kg<sup>-1</sup>), snow from the site away from Yelcho Base (734.5 µg kg<sup>-1</sup>) and snow from La Paloma Glacier 2015 (233.6 µg kg<sup>-1</sup>). BC values observed in Antarctic snow were higher than others previously reported in the literature (Cereceda et al 2019) and showed the influence that anthropic activities have in the study area, considering that the two highest values of BC concentration in snow were found at sites near the bases, which presented levels comparable to those found in snowy sites in the Andes, continental Chile (Cereceda et al 2019).</p>

Sulphur and oxygen isotope signatures of dissolved sulphate in freshwater from King George Island, Antarctic Peninsula

2021 ◽  
pp. 1-3
Author(s):  
Yeongmin Kim ◽  
Insung Lee ◽  
Bernhard Mayer ◽  
Guebuem Kim ◽  
Jong Ik Lee ◽  
...  
Keyword(s):  
Oxygen Isotope ◽  
Antarctic Peninsula ◽  
Ice Cores ◽  
Ion Concentration ◽  
King George Island ◽  
Antarctic Region ◽  
Isotopic Signatures ◽  
Natural Processes ◽  
Sulphur Cycling ◽  
The Antarctic

The sulphate ion (SO42-) is one of major species in freshwater as well as seawater, originating from various natural and anthropogenic processes (Krouse & Mayer 2000). Compared to the Northern Hemisphere, where human activities affect the sulphate concentration and isotopic signatures, the contribution of anthropogenic sulphate is likely to be negligible in freshwater and ice cores in the Antarctic region (Patris et al. 2002). This means that the sulphur and oxygen isotope compositions of the dissolved sulphate could hint at information on the sources, formation and deposition due to various natural processes and sulphur cycling in the Antarctic region, especially for the dissolved sulphate in surface waters such as ponds and creeks (Patris et al. 2000, Kim et al. 2017). Here we report the ion concentration and sulphur and oxygen isotope compositions of the dissolved sulphate in freshwater from King George Island in the Antarctic Peninsula, which provide implications regarding the sources of the dissolved sulphate and the sulphur cycling in the Antarctic region.

scholarly journals Air Temperature and Snow Accumulation in the Antarctic Peninsula During the Past 50 Years (Abstract)

1988 ◽  
Vol 11 ◽  
pp. 207-207 ◽  
Author(s):  
David A. Peel ◽  
Robert Mulvaney
Keyword(s):  
Antarctic Peninsula ◽  
Accumulation Rate ◽  
Ice Sheet ◽  
Ice Cores ◽  
Snow Accumulation ◽  
The West ◽  
Climate Type ◽  
The Past ◽  
The Antarctic ◽  
Noise Factors

Trends in climate affecting the West Antarctic ice sheet may be detected first in the Antarctic Peninsula region. Although the area contains the most comprehensive weather records for any part of Antarctica, reliable snow-accumulation data are lacking.Mainly as a result of the large snow-accumulation rate in the region (typically in the range 4.0–10.0 kg m−2 a−1), stratigraphie evidence of climate derived from ice cores can be resolved in much greater detail than is possible over most of the continent. Ice cores have been drilled at two sites, representing the extremes of climate type encountered in the region. A 133 m core has been obtained from Dolleman Island (70°35.2′S, 60°55.5′W) to represent the continental-type climate of the Weddell coast region, and an 87 m core has been obtained from the Palmer Land plateau (74°01′S, 70°38′W) to represent the more maritime regime of the west coast and central areas. Replicated cores were obtained at both sites in order to assess the contribution of local noise factors to the climatic signal preserved in the cores. Climatic trends during the period 1938–86 have been assessed on the basis of stable-isotope analysis of the top 47 m of the Palmer Land core and of the top 32 m of the Dolleman Island core.A statistical analysis of derived profiles of mean annual δ18O and accumulation rate indicates that the local noise factors at these sites are sufficiently small that data averaged over periods as short as 5 years should reveal climatic shifts at the level of 0.2% and 5% respectively. These changes are much smaller than trends that have actually occurred during the past 50 years.The most notable trend over the past 30 years is an increase of more than 30% in the snow-accumulation rate that has occurred in parallel with an overall temperature increase of 0.06°C/a during the same period. Increases of similar magnitude can be inferred from studies in East Antarctica, and may be related to a significant increase in precipitation rate that has been documented recently at mid-to high-latitude stations in the Northern Hemisphere. The finding may have relevance to studies of the possible consequences of a CO2-induced climate change. More extensive accumulation time series are now required from Antarctica, if satisfactory models of the long-term balance of the ice sheet are to be derived.

scholarly journals Surface energy budget on Larsen and Wilkins ice shelves in the Antarctic Peninsula: results based on reanalyses in 1989–2010

2014 ◽  
Vol 8 (4) ◽  
pp. 1519-1538 ◽  
Author(s):  
I. Välisuo ◽  
T. Vihma ◽  
J. C. King
Keyword(s):  
Antarctic Peninsula ◽  
Weather Conditions ◽  
Surface Fluxes ◽  
Surface Energy Budget ◽  
Japan Meteorological Agency ◽  
Ice Shelf ◽  
Ice Shelves ◽  
Annual Variations ◽  
Net Flux ◽  
The Antarctic

Abstract. Ice shelves in the Antarctic Peninsula have significantly disintegrated during recent decades. To better understand the atmospheric contribution in the process, we have analysed the inter-annual variations in radiative and turbulent surface fluxes and weather conditions over Larsen C Ice Shelf (LCIS) and Wilkins Ice Shelf (WIS) in the Antarctic Peninsula in 1989–2010. Three atmospheric reanalyses were applied: ERA-Interim by ECMWF, Climate Forecast System Reanalysis (CFSR) by NCEP, and JRA-25/JCDAS by the Japan Meteorological Agency. In addition, in situ observations from an automatic weather station (AWS) on LCIS were applied, mainly for validation of the reanalyses. The AWS observations on LCIS did not show any significant temperature trend, and the reanalyses showed warming trends only over WIS: ERA-Interim in winter (0.23 °C yr−1) and JRA-25/JCDAS in autumn (0.13 °C yr−1). In LCIS from December through August and in WIS from March through August, the variations of surface net flux were partly explained by the combined effects of atmospheric pressure, wind and cloud fraction. The explained variance was much higher in LCIS (up to 80%) than in WIS (26–27%). Summer melting on LCIS varied between 11 and 58 cm water equivalent (w.e.), which is comparable to previous results. The mean amount of melt days per summer on LCIS was 69. The high values of melting in summer 2001–2002 presented in previous studies on the basis of simple calculations were not supported by our study. Instead, our calculations based on ERA-Interim yielded strongest melting in summer 1992–1993 on both ice shelves. On WIS the summer melting ranged between 10 and 23 cm w.e., and the peak values coincided with the largest disintegrations of the ice shelf. The amount of melt on WIS may, however, be underestimated by ERA-Interim, as previously published satellite observations suggest that it suffers from a significant bias over WIS.

scholarly journals Air Temperature and Snow Accumulation in the Antarctic Peninsula During the Past 50 Years (Abstract)

1988 ◽  
Vol 11 ◽  
pp. 207 ◽  
Author(s):  
David A. Peel ◽  
Robert Mulvaney
Keyword(s):  
Antarctic Peninsula ◽  
Accumulation Rate ◽  
Ice Sheet ◽  
Ice Cores ◽  
Snow Accumulation ◽  
The West ◽  
Climate Type ◽  
The Past ◽  
The Antarctic ◽  
Noise Factors

Trends in climate affecting the West Antarctic ice sheet may be detected first in the Antarctic Peninsula region. Although the area contains the most comprehensive weather records for any part of Antarctica, reliable snow-accumulation data are lacking. Mainly as a result of the large snow-accumulation rate in the region (typically in the range 4.0–10.0 kg m−2 a−1), stratigraphie evidence of climate derived from ice cores can be resolved in much greater detail than is possible over most of the continent. Ice cores have been drilled at two sites, representing the extremes of climate type encountered in the region. A 133 m core has been obtained from Dolleman Island (70°35.2′S, 60°55.5′W) to represent the continental-type climate of the Weddell coast region, and an 87 m core has been obtained from the Palmer Land plateau (74°01′S, 70°38′W) to represent the more maritime regime of the west coast and central areas. Replicated cores were obtained at both sites in order to assess the contribution of local noise factors to the climatic signal preserved in the cores. Climatic trends during the period 1938–86 have been assessed on the basis of stable-isotope analysis of the top 47 m of the Palmer Land core and of the top 32 m of the Dolleman Island core. A statistical analysis of derived profiles of mean annual δ18O and accumulation rate indicates that the local noise factors at these sites are sufficiently small that data averaged over periods as short as 5 years should reveal climatic shifts at the level of 0.2% and 5% respectively. These changes are much smaller than trends that have actually occurred during the past 50 years. The most notable trend over the past 30 years is an increase of more than 30% in the snow-accumulation rate that has occurred in parallel with an overall temperature increase of 0.06°C/a during the same period. Increases of similar magnitude can be inferred from studies in East Antarctica, and may be related to a significant increase in precipitation rate that has been documented recently at mid-to high-latitude stations in the Northern Hemisphere. The finding may have relevance to studies of the possible consequences of a CO2-induced climate change. More extensive accumulation time series are now required from Antarctica, if satisfactory models of the long-term balance of the ice sheet are to be derived.

scholarly journals Marine diatoms in ice cores from the Antarctic Peninsula and Ellsworth Land, Antarctica – species diversity and regional variability

2021 ◽  
Author(s):  
Dieter R. Tetzner ◽  
Elizabeth R. Thomas ◽  
Claire S. Allen
Keyword(s):  
Antarctic Peninsula ◽  
Temporal Distribution ◽  
Ice Cores ◽  
High Elevation ◽  
Polar Regions ◽  
Regional Variability ◽  
Marine Diatoms ◽  
The Andes ◽  
Glacier Ice ◽  
The Antarctic

Abstract. The presence of marine microfossils (diatoms) in glacier ice and ice cores has been documented from numerous sites in Antarctica, Greenland, as well as from sites in the Andes and the Altai mountains, and attributed to entrainment and transport by winds. However, their presence and diversity in snow and ice, especially in polar regions, is not well documented and still poorly understood. Here we present the first data to resolve the regional and temporal distribution of diatoms in ice cores, spanning a 20 year period across four sites in the southern Antarctic Peninsula and Ellsworth Land, Antarctica. We assess the regional variability in diatom composition and abundance at annual and sub-annual resolution across all four sites. These data corroborate the dominance of contemporary marine diatoms in Antarctic Peninsula ice cores, reveal that the timing and amount of diatoms deposited vary between low and high elevation sites and support existing evidence that marine diatoms have the potential to yield a novel wind paleoenvironmental proxy for ice cores in the southern Antarctic Peninsula and Ellsworth Land.

Nine Centuries of Microparticle Deposition at the South Pole

1982 ◽  
Vol 17 (1) ◽  
pp. 1-13 ◽  
Author(s):  
E. Mosley-Thompson ◽  
L. G. Thompson
Keyword(s):  
Time Scale ◽  
Ice Core ◽  
Ice Cores ◽  
Particulate Material ◽  
Ice Age ◽  
Simultaneous Increase ◽  
Climatic Data ◽  
South Pole ◽  
The South ◽  
The Antarctic

AbstractThe analysis of microparticles in a 101-m core from Amundsen-Scott South Pole Station, Antarctica has revealed a substantial increase in total particle concentration between approximately 1450 and 1850 A.D., a period encompassing the latest neoglacial interval or Little Ice Age. It is likely that this reflects a simultaneous increase in the concentration of particulate material in the Antarctic atmosphere. This is important climatologically, for the Antarctic atmosphere may represent the closest approximation to the natural background aerosol. Thus cores from East Antarctica may contain long and detailed records of the natural global background aerosol. Such records are unavailable from any other medium. Additionally, a cyclical variation which appears to be annual has been detected in the South Pole particle record. These features allow construction of a relative time scale for ice cores older than 100 yr from regions of low accumulation (<10 g a−1) where many traditional techniques are not applicable. This is especially significant, as the comparison of climatic data extracted from ice cores with other records of proxy data depends upon the ability to assign an accurate time scale to the ice core. An estimated nine-century record of net annual accumulation at the South Pole has been compiled and the calculated error in the time scale is ±90 yr.

Sign in / Sign up

Export Citation Format

Share Document