US flag United States National Report
Prepared by: Paul Mayewski
email: paul.mayewski@maine.edu

Page 1

US ITASE Scientific Contributions
US ITASE science activities in West Antarctica (1999-2003) comprise 11 currently funded research programs (Table 1).

Table 1. Currently funded US ITASE research programs in West Antarctica (* denotes expressed interest in 2003-2005 activities).

Investigators Institution Discipline
Mary Albert * CRREL Snow and firn microstructure>
Steve Arcone * CRREL High resolution radar profiling>
Roger Bales * Arizona Hydrogen peroxide, formaldehyde>
David Bromwich * Ohio State Meteorology
Gordon Hamilton * Maine Satellite image analysis
Gordon Hamilton * Maine Mass balance, accumulation rates
Bob Jacobel * St Olaf Deep radar
Paul Mayewski * Maine Glaciochemistry
Dave Meeker UNH Glaciochemistry
Joe McConnell * DRI Trifluoroacetate
Deb Meese * CRREL Stratigraphy
Tony Gow CRREL Stratigraphy
Eric Steig * Washington Stable isotopes
Jim White * Colorado Stable isotopes
Chris Shuman * NASA Stable isotopes



To date, 63 scientific products (abstracts, papers, reports that are published, in press, or at advanced stages of preparation) have been produced by research teams involved in US ITASE (for detailed citations please refer to US ITASE at www.ume.maine.edu/USITASE). In the process, US ITASE has made several major scientific contributions (examples of citations from the literature included):

  1. Field studies to understand features in RADARSAT and other satellite imagery (Shuman and Comiso, 2001; Guo et al., 2003; Hamilton, 2001; Hamilton and Spikes, 2002; Stearns et al., in preparation, Schneider and Steig, in review; Schneider et al., in preparation);
  2. Identification of surface and deep radar reflectors as continuous time-stratigraphic horizons across the thousands of km of traverse route (Arcone, 2002a, b; Arcone et al., 2001a, b, c; Spikes et al., 2001, 2002; Hamilton et al., 2000);
  3. Ice core calibration of radar reflectors in the upper 100 meters of the ice sheet to determine the source of these reflectors (Arcone, 2002a; Arcone et al., 2001a, b, 2002);
  4. Examination of spatial variability in major ions over West Antarctica and relationship to sources (Kreutz and Mayewski, 1999; Kreutz et al., 1999, 2000; Dixon et al., 2001; Isaksson et al., 2001; Kaspari et al., 2002);
  5. Ice core reconstructions of seasonal, interannual and decadal scale variability in accumulation rate, temperature, atmospheric circulation, volcanic activity, and sea ice extent and relation to models (Kreutz and Mayewski, 1999; Reusch et al., 1999; Hamilton et al., 2000; Qin et al., 2000; Guo et al., in review; Guo et al., 2002; Meese and Gow, 2002;Meyerson et al., in review; Isaksson et al., 2001; Souney et al., in review; Palmer et al., 2001; Steig, et al., in preparation; Bertler et al., in review; Dixon et al., 2002);
  6. Identification of ENSO, ACW (Antarctic Circumpolar Wave), PDO (Pacific Decadal Oscillation), EAH (East Antarctic High), and ASL (Amundsen Sea Low) atmospheric circulation structure in glaciochemical time-series, and implications and relationship to models (Kreutz et al., 2000; Mayewski and White, 2002; Meyerson et al., 2002, in review; Bromwich et al., 1999, 2003; Mayewski et al., 2001, Steig et al., 2001, 2002, in preparation; Souney et al., in review; Goodwin et al., in review);
  7. Assessment of modern global climate change (short-term variability in snowfall, temperature, and atmospheric circulation, pollution) in the context of decadal to centennial-scale variability (Reusch et al., 1999; Qin et al., 1999; Hamilton et al., 2000; SCAR ISMASS Committee (including GSH), in preparation; Meese and Gow, 2002);
  8. Deconvolution of local-scale variability in ice core-derived accumulation rate compared to regional scale variability (Hamilton et al., 2000, Arcone et al., 2002);
  9. Glaciological reconnaissance for potential deep drilling sites (Hamilton et al., in preparation; Frey et al., 2002);
  10. High resolution mapping of subglacial topography in previously unexplored regions (Welch and Jacobel, 2001, 2002);
  11. Characterization of ice flow dynamics based on deformation of internal stratigraphy, basal and ice surface topography (Welch and Jacobel, 2001, 2002);
  12. Characterization of basal reflectivity based on changes in basal temperature and/or geology (Welch and Jacobel, 2001, 2002)
  13. Air sampling in the interior of West Antarctica and air-snow processes (Frey et al., 2001, 2002, Albert, in preparation; Albert and Leeman, 2002);
  14. Snow and firn permeability and microstructure measurements at locations with greatly differing accumulation rates and average temperature (Albert, 2001, 2002; Albert and Leeman, 2002, in preparation);
  15. Physical property measurements of annual layer stratigraphy, depth/density profiles and crystal growth profiles as a function of age and in situ temperature in snow pits and ice cores (Gow and Meese, 2002).

US ITASE Technical and Logistical Accomplishments
US ITASE has accomplished the following technical and logistical activities during the 1999-2002 field period; included in parentheses is the expected total following the 2002-2003 field season.

  1. The traverse traveled a total of ~4,000 km (5,500 km) sampling a significant portion of West Antarctica (Figure 1).
  2. Continuous radar observations (crevasse detection (400 MHz) and shallow depth (200 MHz)) over the ~4,000 km (5,500 km) of the traverse route and deep radar (2.5 MHz) over ~2,000 km (~3,500 km).
  3. Occupation of fifteen (20) science sites for periods of 2-6 days depending upon workload per site.
  4. A total of ~1,500 m (~2,100 m) of ice core recovered utilizing both the 3” diameter Eclipse drill purchased by NSF for use by US ITASE and a 2.2” diameter lightweight drill built by Glacier Data for the University of Maine. A total of 16 (20) 3” diameter ice cores collected from 15 (20) sites covering a minimum of 200 years (typically >500-1000 years). Ice cores sampled at NICL for chemistry, stable isotopes, density and total ? activity.
  5. Permeability and porosity experiments conducted at 7 (10) snow pits and using 6 (9) 18 m ice cores returned to CRREL.
  6. Stratigraphy sampled at all sites utilizing snow pits excavated either exclusively for this purpose, or snow pits excavated as access for 3” ice coring, or ~10 m wide pits excavated using a Challenger 55 tractor blade.
  7. Forty-two (60) days of atmospheric and shallow chemistry observations conducted at 10 (15) sites. Sampling includes real-time, continuous observations of peroxides (H2O2 and organic peroxides), formaldehyde, and near-surface ozone profiles and ozone profiles up to an altitude of 23 km.
  8. Basic meteorological observations collected at all sites and 10 m depth temperatures for comparison with infrared satellite estimates of mean annual temperature.
  9. Continuous geodetic-quality GPS profiles along the ~4,000 km (5,500 km) of the traverse route, and continuous base station data collection for ~50 days each season.
  10. Thirteen (18) high precision GPS ‘coffee can’ experiments deployed to calculate mass balance and measure flow velocities.
  11. Three AWS deployed close to the proposed inland deep drilling WAIS site.
Click to enlarge
US ITASE traverse routes and core sites


Location Lat. Long. Elevation Depth Time Period
  (°S) (°W) (m) (m) (Year AD)
South Pole
          

South Pole-95

 90 0 2850 71 1490-1995
           
Siple Dome
          

Siple Dome-94

 81.653 148.99 620.0584 150 (1890) 1964 -1994
           
UP-C
          

UP-C

 82.44 135.97 525 40 1850-1994
           
West Antarctic Plateau Cores          

CWA(A)

 82.3671 119.2855 950 96 1740-1994

CWA(B)

 82.0918 115.2223 1310 90 1740-1994

CWA(C)

 81.7803 111.3365 1690 50 1850-1994

CWA(D)

 81.3723 107.275 1930 51 1850-1994

95-RIDSA

 78.73 116.33 1740 150 (1831) 1964-1995

95-RIDSB Core

 79.46 118.05 1603 60 (1925) 1964-1995

95-RIDSC Core

 80.01 119.43 1530 60 (1905) 1964-1995

99-A Midpoint

 80.62 122.63 ~1350 58 <1700-2000

99-B Swithinbank

 81.2 126.17 ~1040 49 <1700-2000

00-A WAIS

 79.383 111.239 1791 105 <1700-2000

00-C

 78.733 111.497 1674 61 <1700-2000

00-D

 78.433 115.917 1741 60 <1700-2000

00-E

 78.083 120.08 1697 58 <1700-2000

00-F

 77.683 123.995 1827 60 <1700-2000

00-H

 78.332 124 28.7 1639 60 <1700-2000

00-I

 79.133 122.267 1494 63 <1700-2000

01-A

 79.159 104.967 1843 73 <1700-2000

01-B

 77.843 102.91 1336 71 <1700-2000

01-C

 78.12 95.646 1619 70 <1700-2000

01-D

 77.611 92.248 1484 68 <1700-2000

01-E-1

 77.998 89.819 1222 115 <1700-2000
01-E-2
 77.059 89.137 1238 19 <1700-2001

01-F

 76.0968 89.017 1227 18 <1700-2000


Publications:

Albert, M., 2001, Effects of snow and firn ventilation on sublimation rates, in press, Annals of Glaciology 35.

Albert, M. and Leeman, U., 2002, Variations in snow and firn permeability and their potential impact on air-snow transport processes at sites along the International Trans-Antarctic Science Expedition. AGU EOS, spring 2002.

Albert, M. and Leeman, U., in prep., 2002, Impacts of differences in accumulation rates on permeability of snow and firn. In preparation for JGR.

Albert, M., 2002, Vapor transport in snow. Invited chapter in preparation for the book Gas Transport in Porous Media, C. K. Ho, S.W. Webb, J. Wilson, eds. Kluwer Academic Plenum Publishers. To be submitted July 2002.

next page