This data set includes high-resolution ice core records from the Dry Valleys region of Antarctica, and provides interpretations of interannual to decadal-scale climate variability during the last 2000 years (late Holocene). Intermediate-length ice cores (100 to 200 meters) were drilled at four sites along transects in the Taylor and Wright valleys, and analyzed for stable isotopes and major ions. The data set includes high-resolution ice core data for each study site. It also includes mass balance, borehole temperature, and snowpit data for each site, and Global Positioning System (GPS) velocity data for some of the sites. Snow pit data from three additional sites in the same region is also available. Data are available via FTP, in Microsoft Excel (.xls), ASCII text (.txt), and Microsoft Word (.doc) file formats.
DOWNLOADING DATA VIA FTP
Data can be downloaded through a Web browser or command line via FTP. When using a Web browser, the FTP link first directs you to an Optional Registration Form that if filled out, will allow you to receive notifications about updates or processing changes related to that specific data set. After completing the Optional Registration Form, the FTP directory becomes available. For additional help downloading data through an FTP client, go to the How to access data using an FTP client support page.
Late Holocene Climate Variability, Dry Valleys, Antarctica, Version 1
|Spatial Resolution:||Not Specified|
|Temporal Resolution:||Not specified|
|Platform(s)||FIELD INVESTIGATION, FIELD SURVEYS, GPS, LABORATORY|
|Sensor(s):||AWS, GPS, HUMIDITY SENSORS, PRESSURE SENSORS, TEMPERATURE SENSORS|
|Data Contributor(s):||Karl Kreutz, Paul Mayewski|
|Metadata XML:||View Metadata Record|
As a condition of using these data, you must cite the use of this data set using the following citation. For more information, see our Use and Copyright Web page.Kreutz, K. 2009. Late Holocene Climate Variability, Dry Valleys, Antarctica, Version 1. [Indicate subset used]. Boulder, Colorado USA. NSIDC: National Snow and Ice Data Center. doi: http://dx.doi.org/10.7265/N5FF3Q92. [Date Accessed].
Detailed Data Description
Data are available as ASCII text files (.txt) and Microsoft Excel files (.xls). Detailed metadata are available in Microsoft Word files (.doc).
Data are available on the FTP site in the
ftp://sidads.colorado.edu/pub/DATASETS/AGDC/kreutz_nsidc_0399/ directory. The directory is divided into seven main subdirectories, as described in Table 1. The subdirectories are divided into folders for each experimental location, which contain data files and metadata specific to those measurements.
|Directory Name||Directory Contents|
|AWS||Automatic Weather Station (AWS) data for Clark and Commonwealth glaciers, 2004 and 2005|
|Borehole_temperature||Borehole temperature data for the four ice core sites, as measured in 2005|
|GPS_velocity||GPS velocity data for Clark and Commonwealth glaciers, 2004 and 2005
Metadata describing GPS velocity data, in Microsoft Word (.doc) format
|Ice_Core_Data||Ice core melting, density, and chemistry data for each of the four ice core sites|
|Mass_Balance_Pole_Data||Mass balance pole data for each of the four ice core sites
Metadata file describing mass balance measurement method, in Microsoft Word (.doc) format
|Site_Coordinates||Detailed latitude, longitude, and elevation coordinates for each site|
|Snowpit_Data||Snow pit data from the four ice core sites plus three additional sites|
Files are named according to the following convention:
Table 2. File Naming Convention Variable Description xx Site location:
- cl: Clark Glacier
- cm: Commonwealth Glacier
- bl: Blue Glacier
- vu: Upper Victoria Glacier
- ms: Meserve Glacier
- nw: Newall Glacier
- rh: Rhone Glacier
YYYY Four-digit year measurementname Measurement type .zzz File extension
Site_Coordinatesfolder contains latitude, longitude, and elevation coordinates for each site.
The file sizes range from 1 KB to 1759 KB.
The total volume of the data set is 21.5 MB.
Ice core data were collected at four sites in the Dry Valleys region of Antarctica: Blue Glacier, Clark Glacier, Commonwealth Glacier, and Upper Victoria Glacier. Snow pit data were collected at three additional sites: Meserve Glacier, Newall Glacier, and Rhone Glacier. Detailed location information for each site is available in the Site_Coordinatesfolder.
Southernmost Latitude: 78.08º S
Northernmost Latitude: 77.3° S
Westernmost Longitude: 161.04° W
Easternmost Longitude: 163.03° W
Spatial Coverage Map
Data in this collection were obtained during three Antarctic field seasons from 2003 to 2005.
The data set contains high-resolution ice core data, including chemistry, bore hole temperatures, mass balance, AWS weather data, and snow pit data. Detailed location information for each site is available in the
Site_Coordinates folder. Metadata pertaining to specific measurements are available in the respective folders or data spreadsheets. For example, the
Clark_GPS_metadata.doc file provides metadata for the GPS velocity measurements of Clark Glacier. Parameters in the main data file types are described below and in Tables 3 through 7.
1. AWS Data
AWS data are available for two sites, Clark Glacier and Commonwealth Glacier. Table 3 lists the parameters for files in the
|Daily Meteorological Data|
|Day||Day of month|
|AvgIce1T||Average ice temperature|
|AvgIce2T||Average ice temperature|
|AvgIce3T||Average ice temperature|
|AvgAirT||Average air temperature|
|AvgAirRH||Average air relative humidity|
|AirTMax||Maximum air temperature|
|AirMinT||Minimum air temperature|
|Wndspd (S[ms-1])||Wind speed in meters per second|
|Wndspd (U)||Horizontal wind speed|
|AvgWnddir||Average wind direction|
|Sdwnddir||Wind direction standard deviation|
|Distance (m)||Snow depth in meters to snow surface, measured twice daily|
|Pressure (mbar)||Pressure in millibars, measured every three hours|
|Latitude, Longitude||AWS station location|
|Deployed, Collected||Dates of station measurement begin and end (DD-MMM-YY)|
2. Borehole Temperature Data
Borehole_Temperatures contains one data file,
DV_Borehole_Temperatures.xls. These data were collected in the Dry Valleys, Antarctica during the 2005 to 2006 Antarctic field season, using a RBR TR-1050 temperature logger. The file includes borehole data for ice core sites at Clark, Commonwealth and Upper Victoria glaciers.
3. GPS Velocity Data
GPS velocity data were processed in the Trimble Geomatics Office in both WGS84 coordinates (latitude and longitude) and height above ellipsoid (HAE). Additional information relating to GPS data is available in the
Commonwealth_2005_metadata.doc files. Table 4 lists the parameters in the
|Time||Date and time of measurement, in format:
|Point name||Arbitrary name given to each survey point|
|Latitude, Longitude||Latitude and longitude (degrees) of point location|
|Northing, Easting||Universal Transverse Mercator zone 58|
|Semi-major axis (m)||Longest radius of the ellipse|
|Semi-minor axia (m)||Shortest radius of the ellipse|
|Orientation||Degrees from north of the semi-major axis|
|HAE (m)||Height above ellipsoid, referring here to the World Geodetic System 1984 (WGS84) ellipsoid, which approximates the Earth's surface|
|Sigma HAE (m)||Formal error, in meters, excluding setup errors|
|Elevation (m)||Elevation above the geoid, which approximates mean sea level. This elevation is based on a global geoid model and is subject to both the error of the HAE measurement and the error in the geoid model, which is often on the order of meters|
4. Ice Core Data
Table 5 describes the data files in the
|Core density||Depth, weight, tare, and diameter measurements for approximately 1-meter thick ice core sections|
|Core run lengths||Run number and run length for ice core measurements|
|Chemistry: isoions||Sample ID, sample depth, and measurements of the following ions in ug/L:
|Chemistry: trace metals||Sample number, sample depth, and measurements of the following trace metals:
5. Mass Balance Pole Data
Mass balance data were collected by freezing one-inch aluminum conduit poles into the surface of the glacier accumulation zone. The sites were surveyed via static GPS, and a height measurement was taken from the snow surface to the pole top. Height to pole top was re-measured after one year, and the height difference taken to represent net accumulation in that time period. Error in height measurement is estimated to be ±0.5 cm for any given measurement. Table 6 provides parameter information for mass balance data files.
|Pole #||Pole number|
|Height above surface (11/11/2003
|Height of pole above firn surface, in meters or centimeters|
|Accumulation (ice)||Annual accumulation of ice in centimeters|
|Accumulation (we)||Annual accumulation measured in snow water equivalent|
|Comments||Details of pole position with respect to sastrugi and other features|
6. Site Coordinates
Site coordinate data files contain latitude, longitude, and HAE measurements for each snow pit, ice core site, and mass balance pole in the study. The file
2005regionalpitsLatLonElev.xls contains location information for the snow pits at Meserve, Newall, and Rhone glaciers. Additional files contained detailed site information for each measurement at Blue, Clark, Commonwealth, and Upper Victoria glaciers.
7. Snow Pit Data
Snow pit data files include density, sample logs, stratigraphy, temperature, and chemistry measurements for snow pits at seven sites: Blue, Clark, Commonwealth, Meserve, Newall, Rhone, and Upper Victoria glaciers. Table 7provides details on the files and parameter in the
|Snow Pit Densities|
|Snow pit density||File containing depth, weight, and volume measurements and density calculations for samples with a 4cm resolution|
|Snow Pit Sample Logs|
|Snow pit sample logs||File containing sample codes, depth, and collection date for snow samples|
|Depth (cm)||Snow pit depth at measurement, in centimeters|
|Collection date||Date, in format DD-MM-YY|
|Snow Pit Temperatures|
|Depth (cm)||Depth of measurement, in centimeters|
|Temp (°C)||Temperature, degrees Celsius|
|Isoions||File containing ion measurement and measurement depth for the following ions:
|Trace Metals||File containing sample id, sample depth, and sample concentration in micrograms per liter (ug/L) for the following trace metals:
Software and Tools
Data are accessible using standard spreadsheet software.
Data Acquisition and Processing
Intermediate-length ice cores (100-200m) were collected at four sites along transects in Taylor Valley and Wright Valley, and analyzed at high resolution for stable isotopes (d18O, dD), major ions (Na+, Mg2+, Ca2+, K+, NH4+, Cl-, NO3-, SO42-, MSA), and trace elements (Al, Fe, S, Sr, B). Additional measurements include mass balance, borehole temperature, and snow pit data for each site, and Global Positioning System (GPS) velocity data for the Clark and Commonwealth glacier sites. Snow pit data from three additional sites in the same region are also available.
Detailed data acquisition methods are available in the metadata files within the seven data folders, and in the references and related publications listed below.
References and Related Publications
Contacts and Acknowledgments
Dr. Karl Kreutz
Climate Change Institute
236 Sawyer Environmental Research Center
University of Maine
Orono, Maine 04469 USA
Dr. Paul Mayewski
Climate Change Institute
133 Sawyer Environmental Research Center
University of Maine
Orono, Maine 04469 USA
This research was supported by NSF OPP grant 0228052 .
DOCUMENT CREATION DATE
23 April 2009