Physical Sciences and Mathematics Commons^™

An Ice-Core Proxy For Northerly Air Mass Incursions Into West Antarctica, Daniel D. Dixon, Paul Andrew Mayewski, Ian D. Goodwin, Gareth J. Marshall, Rhaelene Freeman, Kirk A. Maasch, Sharon B. Sneed

Earth Science Faculty Scholarship

A 200-year proxy for northerly air mass incursions (NAMI) into central and western West Antarctica is developed from the examination of 19 shallow (21–150 m deep) Antarctic ice-core non-sea-salt (nss) Ca2+ concentration records. The NAMI proxy reveals a significant rise in recent decades. This rise is unprecedented for at least the past 200 years and is coincident with anthropogenically driven changes in other large-scale Southern Hemisphere (SH) environmental phenomena such as greenhouse gas (GHG) induced warming, ozone depletion, and the associated intensification of the SH westerlies. The Hysplit trajectory model is used to examine air mass transport pathways into West …

An Emerging Technique: Multi-Ice-Core Multi-Parameter Correlations With Antarctic Sea-Ice Extent, Sharon B. Sneed, Paul Andrew Mayewski, Daniel A. Dixon

Earth Science Faculty Scholarship

ABSTRACT. Using results stemming from the International Trans-Antarctic Scientific Expedition (ITASE) ice-core array plus data from ice cores from the South Pole and Siple Dome we investigate the use of sodium (Na+), non-sea-salt sulfate (nssSO4 2–) and methylsulfonate (MS–) as proxies for Antarctic sea-ice extent (SIE). Maximum and mean annual chemistry concentrations for these three species correlate significantly with maximum, mean and minimum annual SIE, offering more information and clarification than single ice-core and single species approaches. Significant correlations greater than 90% exist between Na+ and maximum SIE; nssSO4 2– with minimum and mean SIE; and MS– with mean SIE. …

A Spatial Framework For Assessing Current Conditions And Monitoring Future Change In The Chemistry Of The Antarctic Atmosphere, D. A. Dixon, Paul Andrew Mayewski, E. Korotkikh, S. B. Sneed, M. J. Handley, D. S. Introne, T. A. Scambos

Earth Science Faculty Scholarship

This is the first study to measure more than 25 chemical constituents in the surface snow and firn across extensive regions of Antarctica. It is also the first to report total- Cs concentrations. We present major ion, trace element, heavy metal, rare earth element 5 and oxygen isotope data from a series of surface snow samples and shallow firn sections collected along four US ITASE traverses across East and West Antarctica. In each sample we measure dissolved concentrations of Na+, K+, Mg2+, Ca2+, Cl−, NO− 3 , SO2− 4 , and MS− using ion chromatography and total concentrations of Sr, …

Ice Core Record Of Rising Lead Pollution In The North Pacific Atmosphere, E. Osterberg, Paul Andrew Mayewski, Karl J. Kreutz, D. Fisher, Michael Handley, Sharon Sneed, C. Zdanowicz, J. Zheng, M. Demuth, M. Waskiewicz, J. Bourgeois

Earth Science Faculty Scholarship

A high-resolution, 8000 year-long ice core record from the Mt. Logan summit plateau (5300 m asl) reveals the initiation of trans-Pacific lead (Pb) pollution by ca. 1730, and a >10-fold increase in Pb concentration (1981–1998 mean = 68.9 ng/l) above natural background (5.6 ng/l) attributed to rising anthropogenic Pb emissions from Asia. The largest rise in North Pacific Pb pollution from 1970–1998 (end of record) is contemporaneous with a decrease in Eurasian and North American Pb pollution as documented in ice core records from Greenland, Devon Island, and the European Alps. The distinct Pb pollution history in the North Pacific …

Snow Chemistry Across Antarctica, Nancy Bertler, Paul Andrew Mayewski, Alberto Aristarain, P. Barrett, S. Becagli, Ronaldo Torma Bernardo, Xiao Cunde, M. Curran, Qin Dahe, Daniel Dixon, Francisco Adolfo Ferron, H. Fischer, Markus Frey, M. Frezzotti, F. Fundel, Christophe Genthon, R. Gragani, Gordon Hamilton, M. Handley, Sungmin Hong, E. Isaksson, Ren Jiawen, Kokichi Kamiyama, Satoru Kanamori, Eija Karkas, L. Karlöf, S. Kaspari, K. Kreutz, A. Kurbatov, E. Meyerson, Hideaki Motoyama, R. Mulvaney, Zhang Mingjun, H. Oerter, E. Osterberg, M. Proposito, A. Pyne, U. Ruth, Jefferson Cardia Simoes, B. Smith, S. Sneed, Kimmo Teinila, F. Traufetter, R. Udisti, Aki Virkkula, Okitsugu Watanabe, B. Williamson, E. Wolff, Li Zhongqin

Earth Science Faculty Scholarship

An updated compilation of published and new data of major-ion (Ca, Cl, K, Mg, Na, NO₃, SO₄) and methylsulfonate (MS) concentrations in snow from 520 Antarctic sites is provided by the national ITASE (International Trans-Antarctic Scientific Expedition) programmes of Australia, Brazil, China, Germany, Italy, Japan, Korea, New Zealand, Norway, the United Kingdom, the United States and the national Antarctic programme of Finland. The comparison shows that snow chemistry concentrations vary by up to four orders of magnitude across Antarctica and exhibit distinct geographical patterns. The Antarctic-wide comparison of glaciochemical records provides a unique opportunity to improve …

Variability In Accumulation Rates From Gpr Profiling On The West Antarctic Plateau, Vandy B. Spikes, Gordon S. Hamilton, Steven A. Arcone, Susan Kaspari, Paul Andrew Mayewski

Earth Science Faculty Scholarship

Isochronal layers in firn detected with ground-penetrating radar (GPR) and dated using results from ice-core analyses are used to calculate accumulation rates along a 100 km across-flow profile in West Antarctica. Accumulation rates are shown to be highly variable over short distances. Elevation measurements from global positioning system surveys show that accumulation rates derived from shallow horizons correlate well with surface undulations, which implies that wind redistribution of snow is the leading cause of this variability. Temporal changes in accumulation rate over 25-185 year intervals are smoothed to along-track length scales comparable to surface undulations in order to identify trends …

Antarctic Oversnow Traverse-Based Southern Hemisphere Climate Reconstruction, Paul Andrew Mayewski

Earth Science Faculty Scholarship

On 2 January 2003, the U.S. component of the International Trans Antarctic Scientific Expedition (U.S. ITASE) (Figure 1) arrived at the South Pole after completing more than 5000 km of oversnow traverses that included much of west Antarctica and a portion of east Antarctica (Figure 2). During the traverses, which were performed from 1999 through 2003, U.S. ITASE focused on collecting data that will allow the reconstruction of sub-annual scale climate variability and changes in the chemistry of the atmosphere over the last 200+ years.

ITASE is a multi-disciplinary research program supported by 19 nations and endorsed by the Scientific …

Methanesulfonate In The Firn Of King George Island, Antarctica, Jiankang Han, Zichu Xie, Xinping Zhang, Dongsheng Dai, Paul Andrew Mayewski, M. S. Twickler

Earth Science Faculty Scholarship

Methanesulfonate was investigated as a potential contributor to the sulfur budget, based on analysis of a firn core from Collins Ice Cap, King George Island, Antarctica (62°10' S, 58°50' W). The anion was found to be present at a mean concentration of 0.17 μeq L^-1, with a maximum of 0.73 μeq L^-1. Dating based on the δ¹⁸O profile suggests that the principal peaks of methanesulfonate are associated with snow deposited in summer and autumn. A careful examination of MSA, SO₄^2-and nssSO₄^2- profiles indicates that two of the three peaks …

High-Precision Dating Of Volcanic Events (A.D. 1301–1995) Using Ice Cores From Law Dome, Antarctica, Anne S. Palmer, Tas D. Van Ommen, Mark A. J. Curran, Vin Morgan, Joe M. Souney, Paul Andrew Mayewski

Earth Science Faculty Scholarship

A record of volcanic activity over the period A.D. 1301–1995 has been extracted from three Law Dome ice cores (East Antarctica). The record dating is unambiguous at the annual level from A.D. 1807 to 1995 and has an uncertainty of ±1 year at A.D. 1301. Signals from 20 eruptions are preserved in the record, including those of two unknown eruptions with acid deposition beginning in A.D. 1810.8 and A.D. 1685.8. The beginning of the ice core signal from the A.D. 1815 Tambora eruption is observed in the austral summer of A.D. 1816/1817. The mean observed stratospheric transport and deposition time …

The Effect Of Spatial And Temporal Accumulation Rate Variability In West Antarctica On Soluble Ion Deposition, K. J. Kreutz, Paul Andrew Mayewski, L. D. Meeker, M. S. Twickler, S. I. Whitlow

Earth Science Faculty Scholarship

Annually‐dated snowpit and ice core records from two areas of West Antarctica are used to investigate spatial accumulation patterns and to evaluate temporal accumulation rate/glaciochemical concentration and flux relationships. Mean accumulation rate gradients in Marie Byrd Land (11–23 gcm⁻²yr⁻¹ over 150 km, decreasing to the south) and Siple Dome (10–18 gcm⁻²yr⁻¹ over 60 km, decreasing to the south) are consistent for at least the last several decades, and demonstrate the influence of the offshore quasi‐permanent Amundsen Sea low pressure system on moisture flux into the region. Local and regional‐scale topography in both regions appears …

Sea Level Pressure Variability In The Amundsen Sea Region Inferred From A West Antarctic Glaciochemical Record, K. J. Kreutz, Paul Andrew Mayewski, I. I. Pittalwala, L. D. Meeker, M. S. Twickler, S. I. Whitlow

Earth Science Faculty Scholarship

Using European Center for Medium-Range Weather Forecasts (ECMWF) numerical operational analyses, sea ice extent records, and station pressure data, we investigate the influence of sea level pressure variability in the Amundsen Sea region on a West Antarctic (Siple Dome) glaciochemical record. Empirical orthogonal function analysis of the high-resolution Siple Dome multivariate ice core chemical time series record (SDEOF1) documents lower tropospheric transport of sea-salt aerosols to the site. During 1985–1994 the SDEOF1 record of high (low) aerosol transport corresponds to anomalously low (high) sea level pressure (SLP) in the Amundsen Sea region. Spatial correlation patterns between ECMWF monthly SLP fields …

The Weddell Sea Region: An Important Precipitation Channel To The Interior Of The Antarctic Ice Sheet As Revealed By Glaciochemical Investigation Of Surface Snow Along The Longest Trans-Antarctic Route, Qin Dahe, Paul Andrew Mayewski, Ren Jiawen, Xiao Cunde, Sun Junying

Earth Science Faculty Scholarship

Glaciochemical analysis of surface snow samples, collected along a profile crossing the Antarctic ice sheet from the Larsen Ice Shelf, Antarctic Peninsula, via the Antarctic Plateau through South Pole, Vostok and Komsomolskaya to Mirny station (at the east margin of East Antarctica), shows that the Weddell Sea region is an important channel for air masses to the high plateau of the Antarctic ice sheet (>2000 m a.s.l.). This opinion is supported by the following. (1) The fluxes of sea-salt ions such as Na⁺, Mg²⁺ and Cl⁻ display a decreasing trend from the west to the …

Seasonal Variations Of Glaciochemical, Isotopic And Stratigraphic Properties In Siple Dome (Antarctica) Surface Snow, K. J. Kreutz, Paul Andrew Mayewski, M. S. Twickler, S. I. Whitlow, J. W.C. White, C. A. Shuman, C. F. Raymond, H. Conway, J. R. Mcconnell

Earth Science Faculty Scholarship

Six snow-pit records recovered from Siple Dome, West Antarctica, during 1994 are used to study seasonal variations in chemical (major ion and H2O2), isotopic (deuterium) and physical stratigraphic properties during the 1988-94 period. Comparison of dD measurements and satellite-derived brightness temperature for the Siple Dome area suggests that most seasonal dD maxima occur within ±4 weeks of each 1 January. Several other chemical species (H2O2, non-sea-salt (nss) SO42-, methanesulfonic acid and NO3-) show coeval peaks with dD, together providing an accurate method for identifying summer accumulation. Sea-salt-derived species generally peak during winter/spring, but episodic input is noted throughout some years. …

Limited Migration Of Soluble Ionic Species In A Siple Dome, Antarctica, Ice Core, Karl J. Kreutz, Paul Andrew Mayewski, Sallie I. Whitlow, Mark S. Twickler

Earth Science Faculty Scholarship

High-resolution (>10 samples a ^-1) glaciochemical analyses covering the last 110 years from a Siple Dome, Antarctica, ice core reveal limited migration of certain soluble ionic species (methane sulfonic acid, NO₃ and Mg²⁺). Th e observed chemical migration m ay be due in part to seasonal alternation between less acidic winter (from high sea-salt concentrations) and m ore acidic summer (from high marine biogenic acid concentrations) layers, common at coastal sites such as Siple Dome. Exact mechanisms to explain the migration are unclear, although simple diffusion and gravitational movement are unlikely since new peaks are …

Spatial Variability Of Snow Chemistry In Western Dronning Maud Land, Antarctica, Malin Stenberg, Elisabeth Isaksson, Margareta Hansson, Wibjörn Karlén, Paul Andrew Mayewski, Mark S. Twickler, Sallie I. Whitlow, Niels Gundestrup

Earth Science Faculty Scholarship

During the austral summer of 1993-94 a number of 1-2 m deep snow pits were sampled in connection with firn-coring in western Dronning Maud Land, Antarctica. The traverse went from 800 to about 3000 m a.s.l. upon the high-altitude plateau. Profiles of cations (Na⁺, K⁺, Mg²⁺, Ca²⁺), anions (CI^-, NO^3-, SO₄^2-, CH₃SO₃^-) and stable oxygen isotopes (δ¹⁸O) from II snow pits are presented here. Close to the coast 2 m of snow accumulates in about 2-3 years, whilst …

Assessment Of The Record Of The 1982 El Chichón Eruption As Preserved In Greenland Snow, Gregory A. Zielinski, Jack E. Dibb, Qinzhao Yang, Paul Andrew Mayewski, Sallie Whitlow, Mark S. Twickler, Mark S. Germani

Earth Science Faculty Scholarship

Variability in the SO 4 2 - and Cl⁻ time series for the 1980s from 12 shallow snow pits across the Greenland ice sheet is used to evaluate the record of the 1982 El Chichón eruption and the potential for recording a moderate northern equatorial eruption in a single Greenland ice core. Composition of volcanic glass found in spring 1983 snow in one of the pits in the Summit region matches that from El Chichón glass, thereby verifying the deposition of material from the eruption. High Na⁺ and Cl⁻ concentrations in this same layer probably represent deposition …

Major Features Of Glaciochemistry Over The Last 110,000 Years In The Greenland Ice Sheet Project 2 Ice Core, Qinzhao Yang, Paul Andrew Mayewski, Marks S. Twickler, Sallie Whitlow

Earth Science Faculty Scholarship

Major chemical species (Cl⁻, NO 3 - , SO 4 2 - , Na⁺, NH 4 + , K⁺, Mg²⁺, Ca²⁺) and δ¹⁸O covering the last 110,000 years from the Greenland Ice Sheet Project 2 (GISP2) ice core were utilized in this study in order to reconstruct the soluble chemistry of the atmosphere over Greenland and interpret major climate events that have affected the region. During the Holocene the major chemical species and δ¹⁸O do not display any significant relationship. However, a strong inverse correlation was …

Glaciochemistry Of Polar Ice Cores: A Review, Michel Legrand, Paul Andrew Mayewski

Earth Science Faculty Scholarship

Human activities have already modified the chemical composition of the natural atmosphere even in very remote regions of the world. The study of chemical parameters stored in solid precipitation and accumulated on polar ice sheets over the last several hundred thousand years provides a unique tool for obtaining information on the composition of the preindustrial atmosphere and its natural variability over the past. This paper deals with the chemistry of polar ice focused on the soluble mineral (Na⁺, NH₄⁺, K⁺, Ca⁺⁺, Mg⁺⁺, H⁺, F⁻, Cl …

Glaciochemical Studies At Siple Dome, West Antarctica, During The 1996–1997 Season, Karl J. Kreutz, Paul Andrew Mayewski, Mark S. Twickler, Sallie I. Whitlow, L. David Meeker

Earth Science Faculty Scholarship

Deep ice cores collected from the interior of the west antarctic ice sheet and the interice stream ridges along the Siple Coast potentially contain long time-series records of Southern Hemisphere environmental change. One such location is Siple Dome, an approximately l20-kilometer (km) x 250-km ice dome located between ice streams C and D (figure 1). Because of promising results from reconnaissance glaciochemical (Mayewski, Twickler, and Whitlow 1995) and geophysical (Raymond et al. 1995) research, current U.S. deep ice-coring efforts are focused in the area. Drilling at Siple Dome is advantageous for several reasons, including the site's relatively simple geometry and …

Historical Biomass Burning: Late 19th Century Pioneer Agriculture Revolution In Northern Hemisphere Ice Core Data And Its Atmospheric Interpretation, G. Holdsworth, K. Hiuchi, G. A. Zielinski, Paul Andrew Mayewski, M. Wahlen, B. Deck, P. Chylek, B. Johnson, P. Damiano

Earth Science Faculty Scholarship

Ice core data from Yukon and Greenland spanning from ∼1750 to 1950 indicate that between ∼1850 and ≤1910 a clear atmospheric signal exists of an episodic biomass burning event that is referred to as the Pioneer Agriculture Revolution. This is best seen in NH₄⁺ ion and particulate concentrations but also in some limited black carbon concentration data, where for all three quantities maximum levels reach about 3 times the prerevolution background concentrations. Tree cellulose δ¹³C data and some early, controversial, French, air CO₂ data, occurring within the same time interval, are interpreted as providing other …

Depletion Of Atmospheric Nitrate And Chloride As A Consequence Of The Toba Volcanic Eruption, Q. Yang, Paul Andrew Mayewski, G. A. Zielinski, M. Twickler, K. C. Taylor

Earth Science Faculty Scholarship

Continuous measurements of SO₄²⁻ and electrical conductivity (ECM) along the GISP2 ice core record the Toba mega‐eruption at a depth 2590.95 to 2091.25 m (71,000±5000 years ago). Major chemical species were analyzed at a resolution of 1 cm per sample for this section. An ∼6‐year long period with extremely high volcanic SO₄²⁻ coincident with a 94% depletion of nitrate and 63% depletion of chloride is observed at the depth of the Toba horizon. Such a reduction of chloride in a volcanic layer preserved in an ice core has not been observed in any previous studies. The …

Relationship Between Continuous Aerosol Measurements And Firn Core Chemistry Over A 10‐Year Period At The South Pole, M. H. Bergin, E. A. Meyerson, J. E. Dibb, Paul Andrew Mayewski

Earth Science Faculty Scholarship

Before ice core chemistry can be used to estimate past atmospheric chemistry it is necessary to establish an unambiguous link between concentrations of chemical species in the air and snow. For the first time a continuous long‐term record of aerosol properties (aerosol light scattering coefficient, σ_sp , and Ångström exponent, å) at the South Pole are compared with the chemical record from a high resolution firn core (∼10 samples per year) covering the period from 1981 to 1991. Seasonal signals in å, associated with winter minima due to coarse mode seasalt and summer maxima due to accumulation mode sulfate …

Chemical Species Spatial Distribution And Relationship To Elevation And Snow Accumulation Rate Over The Greenland Ice Sheet, Q. Yang, Paul Andrew Mayewski, E. Linder, S. Whitlow, M. Twickler

Earth Science Faculty Scholarship

Major chemical species (Cl⁻, NO⁻₃, SO²⁻₄, Na⁺, K⁺, Mg²⁺, Ca²⁺) from 24 snowpits (sampled at a resolution of 3 cm, total 2995 samples) collected from northern, central, and southern Greenland were used for this investigation. The annual and seasonal (winter and summer) concentration of each chemical species was calculated and used to study the spatial distribution of chemical species over the central portion of the Greenland Ice Sheet. A two-sided t-distribution test (α=0.05) suggests that concentrations of major chemical species in snow do …

Twin Ice Cores From Greenland Reveal History Of Climate Change, More, R. Alley, Paul Andrew Mayewski, D. Peel, B. Stauffer

Earth Science Faculty Scholarship

Two projects conducted from 1989 to 1993 collected parallel ice cores—just 30 km apart— from the central part of the Greenland ice sheet. Each core is more than 3 km deep and extends back 110,000 years. In short, the ice cores tell a clear story: humans came of age agriculturally and industrially during the most stable climatic regime recorded in the cores. Change—large, rapid, and global—is more characteristic of the Earth's climate than is stasis.

Potential Atmospheric Impact Of The Toba Mega‐Eruption ∼71,000 Years Ago, G. A. Zielinski, Paul Andrew Mayewski, L. D. Meeker, S. Whitlow, M. S. Twickler, K. Taylor

Earth Science Faculty Scholarship

An ∼6‐year long period of volcanic sulfate recorded in the GISP2 ice core about 71,100 ± 5000 years ago may provide detailed information on the atmospheric and climatic impact of the Toba mega‐eruption. Deposition of these aerosols occur at the beginning of an ∼1000‐year long stadial event, but not immediately before the longer glacial period beginning ∼67,500 years ago. Total stratospheric loading estimates over this ∼6‐year period range from 2200 to 4400 Mt of H₂SO₄ aerosols. The range in values is given to compensate for uncertainties in aerosol transport. Magnitude and longevity of the atmospheric loading may …

A Century Of Accumulation And Temperature Changes In Dronning Maud Land, Antarctica, Elisabeth Isaksson, Wibjörn Karlén, Niels Gundestrup, Paul Andrew Mayewski, Sallie Whitlow, Mark Twickler

Earth Science Faculty Scholarship

A mass balance program was initiated in the Vestfjella-Heimefrontfjella area of western Dronning Maud Land during the austral summer of 1988–1989. As a part of this program, spatial and temporal variations in snow accumulation and temperature/stable isotopes are measured using shallow firn cores. In this paper we present surface accumulation data and discuss the climatic implications of the stable isotope records from two shallow firn cores. One 30-m-deep core, obtained about 200 km from the coast at 700 m asl (73°36′S, 12°26′W), covers the period 1932–1991. The other core was drilled at about 500 km from the coast at 2900 …

Ice-Core Glaciochemical Reconnaissance In Inland West Antarctica, Karl J. Kreutz, Paul Andrew Mayewski, Mark S. Twickler, Sallie I. Whitlow

Earth Science Faculty Scholarship

To date, the highest resolution ice cores have come from Greenland [the U.S. Greenland Ice Sheet Project 2 (GISP2) and European Greenland Ice Core Project (GRIP)]. The ability to determine annual layering in these cores over at least the past 50,000 years has allowed the reconstruction of a detailed environmental history covering major glacial and interglacial climatic events (e.g., Mayewski et aI. 1994; O'Brien et al. 1995). Although these cores have significantly advanced our understanding of paleoclimatic change in the Northern Hemisphere, questions remain as to whether the two hemispheres have responded synchronously to climate forcing through time. Determining the …

Global Perspective Of Nitrate Flux In Ice Cores, Qinzhao Yang, Paul Andrew Mayewski, Sallie Whitlow, Michael Morrison, Robert Talbot, Jack Dibb, Ernst Linder

Earth Science Faculty Scholarship

The relationships between the concentration and the flux of chemical species(Cl^-, NO₃^-, SO₄^2-, Na⁺, K⁺, NH₄⁺, Mg²⁺, Ca²⁺) versus snow accumulation rate were examined at GISP2 and 20D in Greenland, Mount Logan from the St. Elias Range, Yukon Territory, Canada, and Sentik Glacier from the northwest end of the Zanskar Range in the Indian Himalayas. At all sites, only nitrate flux is significantly(α = 0.05) related to snow accumulation rate. Of all the chemical series, only nitrate concentration data are normally …

Climatic Impact Of The A.D. 1783 Asama (Japan) Eruption Was Minimal: Evidence From The Gisp2 Ice Core, G. A. Zielinski, R. J. Fiacco, Paul Andrew Mayewski, L. D. Meeker, S. Whitlow, M. S. Twickler, M. S. Germani, K. Endo, M. Yasui

Earth Science Faculty Scholarship

Assessing the climatic impact of the A.D. 1783 eruption of Mt. Asama, Japan, is complicated by the concurrent eruption of Laki, Iceland. Estimates of the stratospheric loading of H₂SO₄ for the A.D. 1108 eruption of Asama derived from the SO₄²⁻ time series in the GISP2 Greenland ice core indicate a loading of about 10.4 Tg H₂SO₄ with a resulting stratospheric optical depth of 0.087. Assuming sulfur emissions from the 1783 eruption were only one‐third of the 1108 event yields a H₂SO₄ loading value of 3.5 Tg and a stratospheric …

Two-Hundred-Year Record Of Biogenic Sulfur In A South Greenland Ice Core (20d), P. Y. Whung, E. S. Saltzman, M. J. Spencer, Paul Andrew Mayewski, N. Gundestrup

Earth Science Faculty Scholarship

The concentration of methanesulfonic acid (MSA) was determined in a shallow south central Greenland ice core(20D). This study provides a high-resolution record of the DMS-derived biogenic sulfur in Greenland precipitation over the past 200 years. The mean concentration of MSA is 3.30 ppb(σ = 2.38 ppb,n = 1134). The general trend of MSA is an increase from 3.01 to 4.10 ppb between 1767 and 1900, followed by a steady decrease to 2.34 ppb at the present time. This trend is in marked contrast to that of non-sea-salt sulfate (nss SO₄^2-), which increases dramatically after 1900 due to …