Arctic Research

Eclipse Icefield, Yukon Territory 2002
Eclipse Icefield, Yukon Territory 1996
Devon Ice Cap, Devon Island 1998
Penny Ice Cap, Baffin Island 1995

List of Arctic Ice Core Publications

 

Eclipse Icefield, Yukon Territory 2002
A Glaciochemical Record of Natural and Anthropogenic Environmental Change in the Northwestern North American Arctic

Research Funded by National Science Foundation - Office of Polar Programs

Cameron Wake and Kaplan Yalcin , Climate Change Research Center
Institute for the Study of Earth, Oceans and Space, University of New Hampshire
and
Karl Kreutz, Stable Isotope Laboratory
Institute for Quaternary and Climate Studies, University of Maine

PUBLICATIONS

Yalcin, K, CP Wake, KJ Kreutz, SI Whitlow, Seasonal and spatial variability in snow chemistry at Eclipse Icefield, Yukon Territory, Canada, Geophysical Research Letters, submitted.

Yalcin, K., C.P. Wake, K.J. Kreutz, S.I. Whitlow, Forest fire signals recorded in ice cores from Eclipse Icefield, Yukon Territory, Canada, Journal of Geophysical Research, submitted.

Yalcin, K., C.P. Wake, K.J. Kreutz, M.S. Germani, and S.I. Whitlow, 500+ years of North Pacific volcanism recorded in three ice cores from Eclipse Icefield, Yukon Territory, Canada, manuscript in preparation.

Yalcin, K., C.P. Wake, K.J. Kreutz, M.S. Germani, and S.I. Whitlow, Atmospheric effects of the Katmai, Ksudach and Kuwae eruptions recorded at Eclipse Icefield, manuscript in preparation.

PRESENTATIONS AND REPORTS

  • Fall 2004 AGU Special Session: Paleoclimate Records of North Pacific Climate Variability: Ocean- Atmosphere Interactions

Oral Papers

Posters

Yalcin et al. PowerPoint Presentation: Eclipse Icefield Forest Fire Signals

Wake et al. Poster: Signal ñ to ñ Noise Ratios and Climate Records from the Eclipse Icefield Ice Cores (PDF 27.5 MB)

  • Spring 2004 AGU-CGU Joint Assembly in Montreal

ÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝ Wake et al. PDF Presentation: Paleoclimate Reconstructions along a Vertical Transect in the St. Elias Mountains

ÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝ Yalcin et al. Abstract: Eclipse Icefield Volcanic Signals

OUTREACH

  • May-June 2002 Eclipse 2002 Ice Core Drilling Video (11 minutes; 313 MB)
  • May-June 2002 Eclipse 2002 Ice Core Drilling Video (2 minutes; 17 MB)
  • 17 July 2002 Interview on New Hampshire Public Radio's "The Front Porch"
  • 10 July 2002 Interview on New Hampshire Public TV's "Outlook"
    Interview is from 21:35 to 25:35 minutes
  • 2 June 2002 UNH crew on expedition in the Arctic. Portsmouth Herald
  • Drilling into Earth's History - February 20, 2001 article in The New Hampshire student newspaper

 

REQUESTS FOR ECLIPSE 2002 DATA

 

Please email Principal Investigators Cameron Wake and Karl Kreutz

 

Eclipse 2002 Photo Gallery

 

MAPS

 

…        Circum-Arctic Ice Core Sites Including Eclipse Icefield

…        Ice Cores Sites in the Saint Elias Mountains, Yukon-Alaska

 

OVERVIEW OF ECLISPE ICEFIELD 2002 PROJECT

Three ice cores, 345, 130, and 40 m in length, along with samples from four 4m snowpits were recovered from Eclipse Icefield (60.51 0 N, 139.47 0 W, 3017 m) in the St. Elias Mountains, Yukon Territory, Canada during the 2002 field season. Snowpit and ice core samples will be analyzed for stable isotopes (d18O, dD), major ions (Na+, NH4+, K+, Mg2+, Ca2+, Cl-, NO3-, SO42-), trace elements (Zn, Pb, Hg, Cd, Cu, V, Mn, Ni, As, Al, Fe, Se), and rare earth elements (La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu).Ý In addition, select ice core sections have also been analyzed for 137Cs fallout and volcanic glass composition. The resulting database will provide a continuous, high- resolution record of aerosol and precipitation chemistry in the remote northwestern North America mid- troposphere over the last one thousand years.

 

During the 2002 field season, other research groups recovered new ice cores from a range of elevations in the St. Elias Mountains.Ý These include a 173 m ice core drilled to bedrock at Prospector- Russell Col (5340 m) on Mt. Logan by the Geological Survey of Canada that is expected to provide a record of high- elevation precipitation chemistry extending into the last glacial period.Ý Other ice cores were recovered from King Col (4200 m) by the National Institute of Polar Research, Japan and Bona-Churchill Col (4400 m) in Alaska by the Byrd Polar Research Center at The Ohio State University.Ý Together with the Eclipse ice cores, these cores offer an unprecedented opportunity to construct a three- dimensional view of the paleo- atmosphere by relating chemical changes in the free troposphere to changes in the mid and lower troposphere.Ý

 

Specific objectives to be addressed by the Eclipse 2002 project include:

 

1. Assessment of the spatial variability in glaciochemical signals preserved in snow and ice at Eclipse Icefield.Ý To test the robustness of paleo-environmental reconstructions derived from ice cores, an assessment of the glaciochemical variability at the ice core site must be made to determine the representativeness of an ice core. To this end samples from four snowpits, each covering approximately one year of accumulation, were collected.Ý Furthermore, the three ice core records (Eclipse 1996, Eclipse 2002 Core 2, and Eclipse 2002 Core 3) now available from Eclipse Icefield can also be used to assess the variability in glaciochemical signals over their period of overlap. This analysis will enable determination of the common signal in each record and improve confidence in the use of ice cores from Eclipse Icefield in paleo-environmental reconstructions.

 

2.Ý Extend the ice core record of volcanism in the North Pacific beyond the 20th century and improve our understanding of the volcanic history of this region.Ý Previous work on a 160 m ice core recovered from Eclipse in 1996 has demonstrated that lower elevation sites in the St. Elias Range records a number of moderate sized eruptions in Alaska, the Aleutian Islands, and Kamchatka than are not recorded on the Logan plateau and that tephra from both Alaskan and Kamchatkan volcanoes can be identified in ice cores from the St. Elias Mountains.Ý The development of a longer ice core based paleovolcanic record for this region from Eclipse Icefield incorporating both volcanic acid (SO42-, Cl-) and volcanic glass characterization offers great potential for improving our understanding of the volcanic history of these very active regions. The ice core from Prospector- Russell Col will provide a Holocene record of volcanic eruptions affecting the upper troposphere and stratosphere; however the Eclipse site will provide a complementary record of mid- sized eruptions capable of perturbing atmospheric chemistry and climate on a regional scale over the last several hundred years that are transported primarily in the lower and middle troposphere and hence not well recorded in glaciochemical records from the Logan Plateau.Ý Furthermore, the availability of multiple ice cores from Eclipse Icefield enables assessment of the variability in volcanic signal preservation at Eclipse as well as more robust estimates of the atmospheric sulfate loading and associated climatic impacts of individual eruptions such as the Katmai, Alaska eruption in 1912.Ý

 

3.Ý Develop a record of forest fires using the multiple ice cores available from Eclipse Icefield, Yukon Territory, Canada.Ý An empirical orthogonal function (EOF) analysis on the Eclipse 2002 ice cores shows that the third EOF describes a positive association between high ammonium concentrations and enhancements of potassium and oxalate.Ý Similar chemical enhancements have been reported in forest fire plumes.Ý Large ammonium concentrations spikes, without concurrent enhancements in potassium or oxalate, will also be considered, after robust smoothing to remove the seasonal ammonium signal and estimate background ammonium concentrations.Ý Development of such a record from Eclipse should allow reconstruction of relative forest fire activity in the Yukon and Alaska.

 

4. Develop a detailed history of trace element deposition in the northwestern North American Arctic, assessing both the natural and anthropogenic contributions of various heavy metals and the trends in trace element deposition over time.Ý Glaciochemical records from the Logan Plateau show no increase in SO42- and NO3- concentrations over the past 100-150 years.Ý In contrast, the Eclipse ice core records an increase in sulfate and nitrate that can be related to Eurasian anthropogenic emissions.Ý It can therefore be expected that anthropogenic emissions of other pollutants such as Cd, Pb, V, Mn, Zn, Cr, Co, and Cu have also affected precipitation chemistry in this region and will be detectable in ice cores from intermediate elevation sites in this region. The continuous, high- resolution measurements on the Eclipse ice core will provide continuous depositional histories for these and other Arctic contaminants extending into the pre-industrial period, allowing quantification of the natural versus anthropogenic contributions of these elements and assessment of changing source strengths over time. Ý

 

5.Ý Identify unique chemical tracers for the precise identification of source regions for the crustal dust and anthropogenic contaminants measured in the Eclipse ice core and how these have changed over time.Ý The detailed trace and rare earth element measurements on the Eclipse ice core will enable identification of sources by use of a multi- element tracer system using distinct chemical signatures for different source regions, providing source region identification for both crustal dust and anthropogenic contaminants.ÝÝ Based on an understanding of chemical species input timing, source and relationship to other environmental parameters (e.g., temperature via stable isotopes; moisture flux via accumulation rate) changes in atmospheric circulation patterns will be interpreted through investigation of changes in multivariate glaciochemical time series in order to determine how circulation changes have affected the distribution of contaminants in the northwest North American Arctic.Ý For example, joint analysis of glaciochemical time-series from Eclipse Icefield and observational records of sea level atmospheric pressure shows a strong relationship among certain ionic species concentrations and the magnitude, location, and timing of semi-permanent high and low pressure systems such as the Aleutian and Icelandic Lows and the Siberian High (Wake et al., 2003).Ý These circulation features play a major part in organizing atmospheric circulation, precipitation patterns, storm tracks, and temperature extremes in the Northern Hemisphere.Ý Results will be used to investigate the links between synoptic circulation patterns and contaminant transport and deposition.

Eclipse Icefield, Yukon Territory 1996
Development of a Multi-Parameter Ice Core Record from Eclipse Icefield, St. Elias Mountains, Yukon Territory

Research Funded by National Science Foundation - Office of Polar Programs

Cameron Wake and Barry Keim, Climate Change Research Center
Institute for the Study of Earth, Oceans and Space, University of New Hampshire

PUBLICATIONS

Wake, C.P., K. Yalcin, and N. Gundestrup. (2003). The climate signal recorded in the oxygen isotope, accumulation, and major ion time-series from the Eclipse Ice Core, Yukon Territory. Annals of Glaciology 35, 416-422. article (PDF file)

Yalcin, K., C.P. Wake and M. Germani.Ý (2003).Ý A 100-year record of North Pacific volcanism in an ice core from Eclipse Icefield, Yukon Territory, Canada, Journal ofÝ Geophysical Research 108, 10.1029/2002JD002449.Ý article (PDF file)

Yalcin, K. and C. P. Wake. (2001). Anthropogenic signals recorded in an ice core from Eclipse Icefield, Yukon Territory, Canada. Geophysical Research Letters, 28, 4487-4490. article (PDF file)

Yalcin, K., Anthropogenic and volcanic signals in an ice core from Eclipse Icefield, Yukon Territory, Canada, M.S. thesis, University of New Hampshire, Durham, 2001.

Blake, E.W., C.P. Wake, and M.D. Gerasimoff (1998) The ECLIPSE drill: a field-portable intermediate-depth ice-coring drill. J. Glaciology. 44,175-179. abstract

 

Eclipse 1996 data

 

Major Ions and Stable Isotopes (Excel File 177 KB)

Beta Activity Profile (Excel File 16 KB)

Whitehorse Beta Activity (Excel File 122 KB)

 

Eclipse 1996 Photo Gallery

 

OVERVIEW OF ECLIPSE ICEFIELD 1996 PROJECT

 

A 160-m firn/ice core was recovered from Eclipse Icefield (60.51 0 N, 139.47 0 W, 3017 m elevation), 45 km northeast of Mt. Logan in the summer of 1996 using a new lightweight electromechanical drill developed jointly with Icefield Instruments, Inc. of Whitehorse, Yukon Territory (Blake et al., 1998).Ý The core was continuously sampled in 10 cm segments using ultra- clean techniques and analyzed for major ions (Na+, NH4+, K+, Mg2+, Ca2+, Cl-, NO3-, SO42-) with an ion chromatograph in a dedicated laboratory at the University of New Hampshire and for oxygen isotopes at the Stable Isotope Laboratory in Copenhagen, Denmark. A section of the core from 50 m to 76 m depth was analyzed for beta activity.Ý Analysis of the beta activity profile indicates that average annual accumulation from 1963 to 1996 was 1.38 meters water equivalent per year.Ý Chronology of the Eclipse ice core is based on multi- parameter annual layer counting, the 1963 and 1961 beta activity reference horizons, and SO42- reference horizons provided by volcanic eruptions, some of which are independently verified by major oxide analysis of associated volcanic glass.Ý The resulting time scale indicates that the Eclipse 1996 ice core provides a 100 year record, with dating error in the core estimated to be +/- one year.

 

The sulfate and nitrate time- series from the Eclipse 1996 ice core provides, for the first time, a record of the anthropogenic influence on precipitation chemistry in the remote northwestern North American mid- troposphere over the last century (Yalcin and Wake, 2001),Ý in contrast to ice core data from the summit plateau of Mt. Logan.ÝÝ The annual flux of sulfate at Eclipse began increasing in 1947 and reached peak levels in the 1980s.Ý The nitrate flux shows an increasing trend beginning in the late 1940s, peaks later than sulfate, and shows a less pronounced decrease over the last two decades.Ý Comparison of the Eclipse record with regional emission estimates for total sulfur and nitrogen oxides suggests that Eurasia is the dominant source of pollutants reaching Eclipse.Ý

 

The Eclipse 1996 ice core also provides a record of regionally significant volcanic eruptions in the North Pacific over the last century (Yalcin et al., 2003).Ý Non- sea ñ salt SO42- residuals above a robust spline and an empirical orthogonal function decomposition were used to identify volcanic signatures that are mostly attributable to Alaskan, Aleutian, or Kamchatkan eruptions. Identification of the source volcano responsible for four of these signals was independently verified by major oxide analysis of associated tephra found in the Eclipse ice core and comparison to reference tephras.ÝÝ Applying the same set of statistical analyses to the Mt. Logan Northwest Col ice core demonstrates that many more volcanic events are recorded at Eclipse (32 events) than at nearby Mt. Logan (8 events) over the 86 year period of overlap between the two cores.Ý Since most of the signals at Eclipse are attributable to moderate eruptions in the North Pacific, this result suggests that the Eclipse site provides a more sensitive record of volcanic eruptions in Alaska and Kamchatka that affect primarily the regional troposphere than does the Mt. Logan site.Ý The Eclipse 1996 record of annual volcanic sulfate flux provided by the EOF analysis was used to investigate the effect of volcanic sulfate on instrumental temperature records from the high northern latitudes in general and in the Gulf of Alaska region in particular, with the most pronounced negative temperature anomalies following the exceptionally large 1912 Katmai eruption (Yalcin, 2001).

The high accumulation rate, nearly complete preservation, and detailed chronology of the Eclipse ice core are well suited for comparison of the glaciochemical record with instrumental time series of temperature, precipitation, and sea level pressure (Wake et al., 2003). Results of cross correlation analysis of instrumental temperature records with the Eclipse δ18O time series reveals a significant positive relationship between summertime δ18O at Eclipse and summer (April- September) temperatures at both coastal and interior Alaskan sites. The results indicate that the Eclipse δ18O time series provides a better proxy for regional temperature than does the δ18O time series from Mt. Logan for which only negative correlations were found. Summer accumulation at Eclipse is only significantly correlated with summer precipitation at Haines Junction, YT, reflecting substantial regional variability in precipitation.Ý The δ18O, accumulation, and glaciochemical time series also display significant correlations with the Northern Hemisphere sea level pressure data set, especially between annual variability in sulfate and nitrate deposition at Eclipse and the intensity of the wintertime Siberian High and Aleutian and Icelandic Lows.ÝÝ These results suggest that year-to-year variability in the deposition of pollutants at Eclipse can be linked to changes in atmospheric circulation while long-term trends can be explained by changes in source strength.

These findings illustrate that the Eclipse site samples a distinct air mass with different source regions and transport histories, resulting in a glaciochemical record complementary to, yet distinct from, that available from nearby Mt. Logan.Ý This is illustrated by the presence of anthropogenic sulfate and nitrate signals at Eclipse but not at Mt. Logan, the larger number of volcanic eruptions recorded at Eclipse relative to Mt. Logan, and the significant positive correlations between the Eclipse δ18O record and regional temperature records, while only negative correlations were found with the Mt. Logan δ18O record. This conclusion was also reached by G. Holdsworth of the Arctic Institute of North America who collected snowpit samples and shallow cores from eight different sites in the St. Elias Mountains spanning an elevation range from 1800 to 5630 m, including Eclipse Icefield, and found events such as the 1986 Augustine, Alaska volcanic eruption, forest fires, and radioactive fallout from the Chernobyl nuclear power plant explosion are observed at lower elevation sites such as Eclipse but are ambiguous or absent at high elevation sites on the Logan Plateau, illustrating that differences in site elevation result in distinct glaciochemical records.Ý

 

Devon Ice Cap, Devon Island 1998
A New Ice Core from the Devon Ice Cap, Canadian Arctic: Continued Development of High-Resolution Proxy Records to Evaluate the Regionalization of Climate in the Circum-Arctic

Research Funded by National Science Foundation - Office of Polar Programs

Publications

Murphy, A.M. 2000. A glaciochemical record from the Devon ice cap and late-Holocene reconstruction of past sea-ice extent in the North Water Polynya, eastern Canadian Arctic.Ý M.S. thesis, University of New Hampshire, Durham.

 

OVERVIEW OF DEVON ICE CAP 1998 PROJECT

The primary objective of this research is to develop and interpret time series of major ions, insoluble microparticles, and methanesulfonic acid (MSA) from a new 300 meter long ice core from the Devon Ice Cap, Devon Island, Canada. This is a collaborative project with the Geological Survey of Canada (GSC) and the Nagaoka Institute of Snow and Ice Studies. Oxygen isotope analyses, direct-current solid electric conductivity (ECM) and the melt percent of annual layers will be analyzed by scientists at GSC. The results will provide a continuous, high-resolution (subannual to decadal) multivariate record of Holocene change of the high Arctic. The results will also complement those from the Penny Ice Cap core (Baffin Island). Snowpit studies that were done while coring the first Devon ice core will provide critical information on the modem characteristics of both the glaciochemical species and insoluble microparticles. This new core is necessary to validate or refute those incongruous findings found in the previously drilled Devon Island ice core with other cores drilled around the Canadian High Arctic.

Analyses of all the major soluble and insoluble components of the atmosphere as preserved in the Devon ice core will enable the determination of the composition of the paleoatmosphere in the eastern Canadian Arctic. The results should provide important information on the timing and cause of climatic change during the Holocene and the regionalization of that change. The relationship between sea salt species in the Devon ice core and recent sea-ice extent will provide important data needed to reconstruct relative sea ice extent and the rapidity of changes in that extent over the last 10,000 years. These data may be used to gain a better understanding of how human populations were impacted by sea ice extent. This high-resolution core is critical as major episodic events such as volcanic eruptions and large biomass burning events, which are evident in ice cores, are factored into the analyses. These findings should contribute to the evaluation of spatial variability of anthropogenic emission deposition in the Arctic. The compilation of all the data sets from circum-arctic ice cores will make a major contribution in understanding the impact that the Arctic may have on global change.

Penny Ice Cap, Baffin Island 1995
An Ice Core Derived Multivariate Proxy Record of Holocene Climate Change from the Penny Ice Cap, Baffin Island, Canada

Research Funded by National Science Foundation - Office of Polar Programs

Publications

Fisher, D.A., R.M. Koerner, G.A. Zielinski, C.P. Wake, C.M. Zdanowicz, J.C. Bourgeois, P.A. Mayewski, N. Grummet. 2001.Ý The effects of flowline length evolution on chemistry-delta (super 18) O profiles from Penny ice cap, Baffin Island, Canada.Ý Annals of Glaciology 35, 150-156.

Grumet, N., C.P. Wake, P.A. Mayewski, G.A. Zielinski, S. Whitlow, R.M. Koerner, D.A. Fisher, and J.M. Woollett. 2000. Variability of sea ice extent in Baffin Bay over the last millennium. Climatic Change 49, 129-145.

Zdanowicz, C. M., G. A. Zielinski, C. P. Wake, D. A. Fisher, and R. M. Koerner. 2000. A Holocene record of atmospheric dust deposition on the Penny Ice Cap, Baffin Island, Canada. Quaternary Research. 53, 62-69. abstract

Zdanowicz, C.M. 1999.Ý Paleoclimatic significance of insoluble micro particle records from Canadian Arctic and Greenland ice cores. Ph.D. dissertation, University of New Hampshire, Durham.

Fisher, D. A., R. M. Koerner, J. C. Bourgeois, G. Zielinski, C. P. Wake, C. U. Hammer, H. B. Clausen, N. Gundestrup, S. Johnsen, K. Goto-Azuma, T. Hondoh, E. Blake, and M. Gerasimoff. 1998. Penny Ice Cap Cores, Baffin Island, Canada, and the Wisconsinan Foxe Dome Connection: Two states of Hudson Bay ice cover. Science. 279, 692-695. abstract PDF full article

Grumet, N. S., C. P. Wake, G. A. Zielinski, D. Fisher, R. Koerner, and J. D. Jacobs. 1998. Preservation of glaciochemical time-series in snow and ice from the Penny Ice Cap, Baffin Island. Geophysical Research Letters. 25, 357-360. abstract PDF full article

Zdanowicz, C. M., G. A. Zielinski, and C. P. Wake. 1998. Characteristics of modern atmospheric dust deposition in snow on the Penny Ice Cap, Baffin Island, Arctic Canada. Tellus. 50B. 506-520. abstract

 

Penny Ice Cap 1995 Photo Gallery

 

OVERVIEW OF PENNY ICE CAP 1995 PROJECT

We collected a 334-meter-long, surface-to-bottom ice core through the Penny Ice Cap, Baffin Island, Canada, and have analyzed and interpreted time series of major ions (sodium, ammonium, potassium, magnesium, calcium, chloride, nitrate, sulfate), insoluble microparticles, and MSA. Oxygen isotope ratios, ECM, laser particulates and percentage of annual melt layers will be analyzed by members of the Geological Survey of Canada. This will allow us to develop a continuous, high-resolution multivariate record of Holocene climate change in this critical area of the Arctic. Such a multivariate record will be the first of its kind recovered from the Canadian Arctic. This project is part of a cooperative agreement between the Glacier Research Group at the University of New Hampshire and the Geological Survey of Canada as the initial component of a program to reconstruct paleoclimatic conditions in the circum-Arctic region. - Snowpit studies and aerosol sampling during the duration of the project will provide critical information on the modem depositional patterns of these glaciochemical species, their spatial variability and air-snow transfer functions.

The smaller size and lower elevation of the Penny Ice Cap compared to Summit, Greenland (site of the GISP2 and GRIP ice cores) will enable us to develop time series of major chemical species that will provide information on additional aspects of Holocene paleoenvironmental conditions in the Arctic (as outlined below) not necessarily available from, and therefore complementing the results of the Greenland cores. Our analysis of all the major soluble and insoluble components of the atmosphere as recorded in the ice core, in conjunction with the use of mathematical and statistical techniques, will allow us to: 1) determine the composition of the paleoatmosphere in the eastern Canadian Arctic which will provide information on the timing and cause of climate change during the Holocene, 2) postulate the temporal variation of synoptic circulation patterns in the North Atlantic (i.e., the size of the polar cell and the frequency of the prevalence of low pressure systems over Davis Strait-Baffin Bay) and their relationship to sea-ice extent, 3) develop and evaluate a record of episodic events such volcanic eruptions and large biomass burning events that modify the chemical content of the atmosphere and effect biogeochemical cycles and climate over short time periods, 4) develop a detailed historical record of the winter time influx of Arctic Haze (a phenomenon not observed in the Greenland cores), 5) establish a well-defined chronology of paleoenvironmental change that can be used to fine-tune other proxy records from Baffin Island, 6) produce a detailed record of atmospheric chemistry and climatic changes associated with deglaciation of the Laurentide Ice Sheet during the mid- to early Holocene (such as the opening of Hudson Strait and the increased exposure of ice-free terrain), 7) further evaluate the regional aspects of climate change in the Arctic through comparisons with other ice core records from Greenland and Mt. Logan, Yukon Territory, 8) determine vertical distribution of chemical species in the atmosphere by comparisons of aerosol chemistry records with those from Alert, Ellesmere Island, and 9) develop very detailed records of aerosol deposition from recent volcanic eruptions in snowpits for comparison with real-time satellite data on these eruptions.