Changes in continental and sea-salt atmospheric loadings in central Greenland during the most recent deglaciation: model-based estimates

AbstractBy fitting a very simple atmospheric impurity model to high-resolution data on ice accumulation and contaminant fluxes in the GISP2 ice core, we have estimated changes in the atmospheric concentrations of soluble major ions, insoluble particulates and10Be during the transition from glacial to Holocene conditions. For many species, changes in concentration in the ice typically overestimate atmospheric changes, and changes in flux to the ice typically underestimate atmospheric changes, because times of increased atmospheric contaminant loading are also times of reduced snowfall. The model interpolates between the flux and concentration records by explicitly allowing for wet- and dry-deposition processes. Compared to the warm Preboreal that followed, we estimate that the atmosphere over Greenland sampled by snow accumulated during the Younger Dryas cold event contained on average four–seven times the insoluble particulates and nearly seven times the soluble calcium derived from continental sources, and about three times the sea salt but only slightly more cosmogenic10Be.

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The calcium-dust relationship in high-resolution data from Dome C, Antarctica

Climate of the Past Discussions ◽

10.5194/cpd-7-1113-2011 ◽

2011 ◽

Vol 7 (2) ◽

pp. 1113-1137 ◽

Cited By ~ 6

Author(s):

F. Lambert ◽

M. Bigler ◽

J. P. Steffensen ◽

M. Hutterli ◽

H. Fischer

Keyword(s):

High Resolution ◽

Ice Core ◽

Calcium Content ◽

Depth Resolution ◽

Dust Particles ◽

Radiation Balance ◽

High Resolution Data ◽

The Past ◽

Low Correlation ◽

Soluble Calcium

Abstract. Ice core data from Antarctica provide detailed insights into the characteristics of past climate, atmospheric circulation, as well as changes in the aerosol load of the atmosphere. We present high-resolution records of soluble calcium (Ca2+), non-sea-salt soluble calcium (nssCa2+), and insoluble mineral aerosol dust from the East Antarctic Plateau at a depth resolution of 1 cm, spanning the past 800 000 yr. The comparison shows that the ratio of ionic proxies such as CaCa2+ (or nssCa2+) to particulate dust aerosol is variable in time. Accordingly, the insoluble dust record is representative of large and small atmospheric particulate dust load changes and better suited to quantify the aerosol effect on the radiation balance in the past. In contrast soluble dust proxies such as Ca2+ and nssCa2+ will underestimate this effect but may be better suited to quantify the deposition of chemically active Ca2+ or other soluble dust derived nutrients into the Southern Ocean. The correlation between nssCa2+ and particulate dust is time dependent with high correlations during glacial and low correlation during interglacial times. The low correlation during warm times may be partly caused by changes in the soluble calcium content of dust particles, possibly due to a more acidic atmosphere during interglacials. The ratio of nssCa2+ to dust is dependent on the dust concentration itself. A simple mixing of two dust end members for glacial and interglacial conditions with nssCa2+ to dust ratios of 0.045 and approximately 0.3, respectively, can explain the overall temporal change in the nssCa2+ to dust ratio over time.

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Seasonal characteristics of the major ions in the high-accumulation Dome Summit South ice core, Law Dome, Antarctica

Annals of Glaciology ◽

10.1017/s0260305500017778 ◽

1998 ◽

Vol 27 ◽

pp. 385-390 ◽

Cited By ~ 26

Author(s):

Mark A.J. Curran ◽

Tas D. Van Ommen ◽

Vin Morgan

Keyword(s):

Major Ions ◽

Seasonal Pattern ◽

Ice Core ◽

Chemical Species ◽

Sea Salt ◽

Seasonal Cycles ◽

High Accumulation ◽

Sea Ice Extent ◽

Seasonal Characteristics ◽

Polar Snow

Seasonal cycles of the chemical species Na+, Κ+ , Mg2+, Ca2+, CH3SO3 (MSA) Cl− NO3 − and NO3 − in the Dome Summit South (DSS) ice core from Law Dome were measured for a number of epochs (AD 1809-15, 1821-31 1980-92) span-nine a total of 28 years. These preliminary trace-chemical patterns show that the DSS site is mainly affected by marine air. The main features found in the seasonal pattern of sea-salt concentrations (e.g. Na+, Cl− and Mg2+) were a winter peak and a summer minimum. The variations in sea salts are believed to reflect aerosol production and transport due to the level of storminess, and are less affected by sea-ice extent. The seasonal cycles of marine biogenic compounds, non-sea-salt SO4 2- and MSA are in good agreement. They show a characteristic summer maximum arid a winter minimum, due to variations in biological activity. While the main sources of nitrate in polar snow remain unclear, the seasonal signal, including sub-seasonal structure, at DSS resembles that found m the atmosphere at coastal Antarctic sites. However, the timing of the nitrate maximum is different in the ice-core record compared with the aerosol records. Overall, the results indicate that the DSS core, with sub-seasonal resolution, contains a sensitive record for investigating climate variability.

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Seasonal characteristics of the major ions in the high-accumulation Dome Summit South ice core, Law Dome, Antarctica

Annals of Glaciology ◽

10.3189/1998aog27-1-385-390 ◽

1998 ◽

Vol 27 ◽

pp. 385-390 ◽

Cited By ~ 35

Author(s):

Mark A.J. Curran ◽

Tas D. Van Ommen ◽

Vin Morgan

Keyword(s):

Major Ions ◽

Seasonal Pattern ◽

Ice Core ◽

Chemical Species ◽

Sea Salt ◽

Seasonal Cycles ◽

High Accumulation ◽

Sea Ice Extent ◽

Seasonal Characteristics ◽

Polar Snow

Seasonal cycles of the chemical species Na+, Κ+ , Mg2+, Ca2+, CH3SO3 (MSA) Cl− NO3 − and NO3 − in the Dome Summit South (DSS) ice core from Law Dome were measured for a number of epochs (AD 1809-15, 1821-31 1980-92) span-nine a total of 28 years. These preliminary trace-chemical patterns show that the DSS site is mainly affected by marine air. The main features found in the seasonal pattern of sea-salt concentrations (e.g. Na+, Cl− and Mg2+) were a winter peak and a summer minimum. The variations in sea salts are believed to reflect aerosol production and transport due to the level of storminess, and are less affected by sea-ice extent. The seasonal cycles of marine biogenic compounds, non-sea-salt SO4 2- and MSA are in good agreement. They show a characteristic summer maximum arid a winter minimum, due to variations in biological activity. While the main sources of nitrate in polar snow remain unclear, the seasonal signal, including sub-seasonal structure, at DSS resembles that found m the atmosphere at coastal Antarctic sites. However, the timing of the nitrate maximum is different in the ice-core record compared with the aerosol records. Overall, the results indicate that the DSS core, with sub-seasonal resolution, contains a sensitive record for investigating climate variability.

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Soluble Impurities in Four Antarctic Ice Cores Over the Last 30 000 Years

Annals of Glaciology ◽

10.1017/s0260305500004274 ◽

1988 ◽

Vol 10 ◽

pp. 116-120 ◽

Cited By ~ 42

Author(s):

Michel R. Legrand ◽

Robert J. Delmas

Keyword(s):

Atmospheric Chemistry ◽

Major Ions ◽

Ice Core ◽

Ice Cores ◽

Sea Salt ◽

The Past ◽

Study Sites ◽

The Last Glacial Maximum ◽

The Last Glacial

The chemical composition of soluble impurities along the Dome C ice core covering approximately the last 30 000 years is reported and interpreted in terms of atmospheric contributions. Terrestrial and sea-salt inputs are known to have been much higher during the Last Glacial Maximum (LGM) than during the Holocene period. For this reason, the gas-derived compounds (mainly H2SO4 and HNO3) which dominate the chemistry of present-day snow are minor components in LGM snow. The exact calculation of each of the various contributions has been made possible by the determination of all major ions (H+, Na+, K+, NH4 +, Mg2+, Ca2+, NO3 −, SO4 2− and Cl−) in the samples. Three additional deep ice cores from other Antarctic areas have also been analyzed, but in a less comprehensive manner than the Dome C core. The differences observed at the four study sites increase the general understanding of the past atmospheric chemistry of the Southern Hemisphere.

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Comparison of analytical methods used for measuring major ions in the EPICA Dome C (Antarctica) ice core

Annals of Glaciology ◽

10.3189/172756402781817022 ◽

2002 ◽

Vol 35 ◽

pp. 299-305 ◽

Cited By ~ 34

Author(s):

Geneviève C. Littot ◽

Robert Mulvaney ◽

Regine Röthlisberger ◽

Roberto Udisti ◽

Eric W. Wolff ◽

...

Keyword(s):

High Resolution ◽

Ion Chromatography ◽

Major Ions ◽

Full Range ◽

Ice Core ◽

Flow Analysis ◽

Ice Cores ◽

High Resolution Data ◽

Wide Range

AbstractIn the past, ionic analyses of deep ice cores tended to consist of a few widely spaced measurements that indicated general trends in concentration. the ion-chromatographic methods widely used provide well-validated individual data, but are time-consuming. the development of continuous flow analysis (CFA) methods has allowed very rapid, high-resolution data to be collected in the field for a wide range of ions. In the European Project for Ice Coring in Antarctica (EPICA) deep ice-core drilling at Dome C, many ions have been measured at high resolution, and several have been analyzed by more than one method. the full range of ions has been measured in five different laboratories by ion chromatography (IC), at resolutions of 2.5–10 cm. In the field, CFA was used to measure the ions Na+, Ca2+, nitrate and ammonium. Additionally, a new semi-continuous in situ IC method, fast ion chromatography (FIC), was used to analyze sulphate, nitrate and chloride. Some data are now available to 788 m depth. In this paper we compare the data obtained by the three methods, and show that the rapid methods (CFA and FIC) give an excellent indication of trends in ionic data. Differences between the data from the different methods do occur, and in some cases these are genuine, being due to differences in speciation in the methods. We conclude that the best system for most deep ice-core analysis is a rapid system of CFA and FIC, along with in situ meltwater collection for analysis of other ions by IC, but that material should be kept aside for a regular check on analytical quality and for more detailed analysis of some sections.

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A continuous 293-year record of volcanic events in an ice core from Lambert Glacier basin, East Antarctica

Antarctic Science ◽

10.1017/s0954102011000897 ◽

2012 ◽

Vol 24 (3) ◽

pp. 293-298 ◽

Cited By ~ 8

Author(s):

R.X. Li ◽

C.D. Xiao ◽

S.B. Sneed ◽

M. Yan

Keyword(s):

Major Ions ◽

Accumulation Rate ◽

Ice Core ◽

Volcanic Eruptions ◽

Sea Salt ◽

High Definition ◽

Volcanic Events ◽

Definition Of ◽

Lambert Glacier ◽

Lambert Glacier Basin

AbstractDuring the 18th Chinese National Antarctic Research Expedition (CHINARE-18, 2001–2002), a 102.18 m ice core was drilled at site LGB69 (70°50′06.6′′S, 77°04′28.9′′E, 1850 m a.s.l., accumulation rate 70 cm yr-1), located to the east of the Lambert Glacier basin. This ice core has been analysed for chemical composition. Based on the high definition of seasonal variations of major ions, the ice core was dated to cover 293 years (ad 1708–2001), with errors at the bottom end within ± 2 years. The non-sea salt SO42- time series provides a proxy for historical volcanic eruptions preserved in the core, and high non-sea salt SO42- concentrations are well correlated to some documented volcanic events, such as Tambora (ad 1815), Cosiguina (ad 1835), Krakatoa (ad 1883) and Tarawera (ad 1886).

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Comprehensive 1000 year climatic history from an intermediate-depth ice core from the south dome of Berkner Island, Antarctica: methods, dating and first results

Annals of Glaciology ◽

10.3189/172756404781814104 ◽

2004 ◽

Vol 39 ◽

pp. 146-154 ◽

Cited By ~ 12

Author(s):

Urs Ruth ◽

Dietmar Wagenbach ◽

Robert Mulvaney ◽

Hans Oerter ◽

Wolfgang Graf ◽

...

Keyword(s):

Major Ions ◽

Accumulation Rate ◽

Ice Core ◽

Regional Scale ◽

Temporal Variations ◽

Sea Salt ◽

The South ◽

Austral Spring ◽

The Core ◽

The North

AbstractA 181 m deep ice core drilled in 1994/95 on the south dome of Berkner Island, Antarctica, was analyzed for stable isotopes, major ions and microparticle concentrations. Samples for ion chromatography were prepared by using a novel technique of filling decontaminated sample from a device for continuous ice-core melting directly into the sample vials. The core was dated through identification of volcanic horizons and interpolative layer counting. The core, together with a similar core from the north dome, reveals a 1000 year history of relatively stable climate. Temporal variations in the two cores deviate from each other owing to changing patterns of regional-scale circulation; the best correspondence between them is found for MSA–. δ18O, accumulation rate and a sea-salt proxy show only negligible correlation, which suggests a complex meteorological setting. Increasing annual accumulation is observed for the last 100 years. A period of increased sea-salt concentrations started around AD 1405, as has also been observed in other cores. Microparticle concentrations are on average 1220 particles (>1.0 μm diameter) mL–1; they are enhanced from AD 1200 to 1350, possibly because of a higher atmospheric mineral dust load or because local volcanic activity was stronger than previously thought. Microparticles and NH4+ show marked but multiple and very irregular sub-annual peaks; long-term stacking of 1 year data intervals yields seasonal maxima in austral spring or mid-summer, respectively. Post-depositional redistribution was observed for MSA, NO3– and F– at volcanic horizons.

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Soluble Impurities in Four Antarctic Ice Cores Over the Last 30 000 Years

Annals of Glaciology ◽

10.3189/s0260305500004274 ◽

1988 ◽

Vol 10 ◽

pp. 116-120 ◽

Cited By ~ 6

Author(s):

Michel R. Legrand ◽

Robert J. Delmas

Keyword(s):

Atmospheric Chemistry ◽

Major Ions ◽

Ice Core ◽

Ice Cores ◽

Sea Salt ◽

The Past ◽

Study Sites ◽

The Last Glacial Maximum ◽

The Last Glacial

The chemical composition of soluble impurities along the Dome C ice core covering approximately the last 30 000 years is reported and interpreted in terms of atmospheric contributions. Terrestrial and sea-salt inputs are known to have been much higher during the Last Glacial Maximum (LGM) than during the Holocene period. For this reason, the gas-derived compounds (mainly H2SO4 and HNO3) which dominate the chemistry of present-day snow are minor components in LGM snow. The exact calculation of each of the various contributions has been made possible by the determination of all major ions (H+, Na+, K+, NH4+, Mg2+, Ca2+, NO3−, SO42− and Cl−) in the samples. Three additional deep ice cores from other Antarctic areas have also been analyzed, but in a less comprehensive manner than the Dome C core. The differences observed at the four study sites increase the general understanding of the past atmospheric chemistry of the Southern Hemisphere.

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Ice-Core Pollen Record of Climatic Changes in the Central Andes during the last 400 yr

Quaternary Research ◽

10.1016/j.yqres.2005.06.001 ◽

2005 ◽

Vol 64 (2) ◽

pp. 272-278 ◽

Cited By ~ 59

Author(s):

Kam-biu Liu ◽

Carl A. Reese ◽

Lonnie G. Thompson

Keyword(s):

Little Ice Age ◽

Ice Core ◽

Climatic Changes ◽

Ice Age ◽

Striking Similarity ◽

Pollen Record ◽

Dry Period ◽

Proxy Records ◽

Ice Cap ◽

Ice Accumulation

AbstractThis paper presents a high-resolution ice-core pollen record from the Sajama Ice Cap, Bolivia, that spans the last 400 yr. The pollen record corroborates the oxygen isotopic and ice accumulation records from the Quelccaya Ice Cap and supports the scenario that the Little Ice Age (LIA) consisted of two distinct phases�"a wet period from AD 1500 to 1700, and a dry period from AD 1700 to 1880. During the dry period xerophytic shrubs expanded to replace puna grasses on the Altiplano, as suggested by a dramatic drop in the Poaceae/Asteraceae (P/A) pollen ratio. The environment around Sajama was probably similar to the desert-like shrublands of the Southern Bolivian Highlands and western Andean slopes today. The striking similarity between the Sajama and Quelccaya proxy records suggests that climatic changes during the Little Ice Age occurred synchronously across the Altiplano.

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