Greenland Snow Pit and Core Stratigraphy (Analog and Digital Formats)

This data set is comprised of scientific field study notebooks from geologist Carl S. Benson describing his traverses of Greenland from 1952 to 1955. The notebooks contain data on Greenland snow accumulation, snow temperature, stratigraphy, ice sheet facies, and snow densification. Dr. Benson's notebooks also include a supplementary 1956 snow accumulation study done by the U.S. Air Force. The notebooks have been scanned and put into PDF format. In addition, a compendium of Greenland snow accumulation data, compiled by Dr. Benson in 1986, is included that spans 1911 to 1981. It is in ASCII text format.

Summary
Detailed Data Description
Data Access and Tools
References and Related Publications
Contacts
Document Information

Citing These Data

The following example shows how to cite the use of this data set in a publication. For more information, see our Use and Copyright Web page.

Benson, Carl S. 2013. Greenland Snow Pit and Core Stratigraphy (Analog and Digital Formats). Boulder, Colorado USA: National Snow and Ice Data Center.

Overview

Parameters	Snow Accumulation Snow Density/Ram Hardness Snow Depth Snow Facies Snow Stratigraphy Snow/Ice Temperature Glacier Thickness/Ice Sheet Thickness Ice Depth/Thickness Ice Sheets Ice Core Records
Spatial Coverage	Southernmost Latitude: 69° N Northernmost Latitude: 78° N Westernmost Longitude: 69° W Easternmost Longitude: 38° W
Temporal Coverage	Notebooks: 1952-1956 Compendium: 1911-1981
Data Format	Notebooks: PDF and hard-copy notebooks Compendium: ASCII Text
Metadata Access	View Metadata Record
Data Access	Digitally scanned notebooks and compendium: FTP Hard copy notebooks: On-site use only by appointment (library@nsidc.org)

1. Summary

Dr. Carl S. Benson, currently professor emeritus at University of Alaska, Fairbanks, worked with the Snow, Ice, and Permafrost Research Establishment (SIPRE now CRREL) from 1951 to 1956 to acquire these data (Brewster 2001). Work on the 1952-55 Greenland traverse snow project was performed for the Snow and Ice Basic Research Branch of the U.S. Army Corps of Engineers under James A. Bender, chief (Benson 1962).

According to Dr. Benson, the study was undertaken for the following reasons.

"A primary question about ice masses of the world today concerns their material balance; i. e., are they in balance with present-day climate or not? In order to answer this question it is necessary to know current rates of accumulation and ablation. A major part of this study is the determination of the amount and distribution of accumulation on the Greenland ice sheet. But the basic purpose has been to extend our knowledge of the overall physical environment of the ice sheet - the accumulation picture is only a part of this. Improvement in our knowledge of the Greenland ice sheet contributes to understanding the nature of ice sheets in general, including extinct ones of the Pleistocene. The primary objective of this study is to demonstrate that the methods of stratigraphy and sedimentation can be successfully applied to the study of snow and firn." (Benson 1962).

During a four-year period from 1952 through 1955, Carl Benson, along with many other individuals and several other organizations, dug and studied 146 snow pits and made 288 supplementary snow hardness profiles with a ramsonde instrument along a 1100 mile traverse in Northwest Greenland (Benson 1962). See Figure 1 for the traverse route. For each exposed pit, temperature, density, ram hardness, and grain size were measured. The data in the notebooks include a listing of all pit locations, a summary matrix of data collected at each station; accumulation data adjusted for Fall 1954 and Fall 1955 reference horizons; average accumulation for all stations; integrated ram hardness (snow density); descriptive stratigraphy, pit profile temperature and density; and pit and core temperature, density, ram hardness, and stratigraphy for each location. Benson's notebooks for 1952 through 1954 were scanned at NSIDC and are available via FTP. As of January 2013, the 1955 notebooks are still in the process of being digitized. The physical notebooks are available for use on-site at NSIDC by appointment.

A good summary and description of this study is provided in Stratigraphic Studies in the Snow and Firn of the Greenland Ice Sheet (Benson 1962). You can download a reprint of this paper from the Defense Technical Information Center Web site.

Figure 1. Location of traverse across Northwest Greenland (red line) (adapted from Benson 1962). Click for larger view.

2. Detailed Data Description

Table 1 shows the number of stations for each year. The locations of each station can be found in the files in the 01-Benson-Introduction directory on the FTP site.

**Table 1.** Number of Stations per Year
Year	No. of Stations
1952	7
1953	43
1954	67
1955	184

File Format, Directory Structure, and Naming Convention

Field Notebooks

The notebooks were scanned to create PDF-format files. The files, available via FTP, are organized in directories in a way that mimics how Carl Benson organized his notebooks. For example, Dr. Benson organized his notebooks into 7 groups of physical folders with a title on the outside of each group. The directory structure mimics this folder organization and has directory names with the same (or a very similar) name as on the physical folder. In addition, to preserve the order of the directories and files as organized by Dr. Benson, we added a 2-digit sequential prefix to all names. See Table 2.

These data reside on the FTP site in the G10004/field-notebooks directory. Table 2 describes the directory structure of this directory on the FTP site.

**Table 2.** Top Level Directory Structure
Directory Name (click name to open that directory)	Description
01-Benson-Introduction	Contains an introduction and description of the study, a summary of all sampling stations, a summary matrix of data collected at each station, accumulation data adjusted for Fall 1954 and Fall 1955 reference horizons, average accumulation for all stations, and integrated ram hardness (snow density). See Table 3 for a list and description of the files in this directory.
02-Meteorological-Data-Party-Crystal-1954	Contains scanned meteorological data sheets with data taken at a sampling of stations during the 1954 traverse.
03-French-Central-Station	Contains a supplementary snow pit data set conducted by the U.S. Air Force in 1956.
04-Greenland-Pit-Data-1952	Contains the scanned data sheets for the entire 1952 traverse. This directory is further broken up into subdirectories named by station number. The PDF files within them are named by date (DDMMMYYYY).
05-Greenland-Pit-Data-1953	Contains the scanned data sheets for the entire 1953 traverse. This directory is further broken up into subdirectories named by station number. The PDF files within them are named by date (DDMMMYYYY).
06-Greenland-Pit-Data-1954	Contains the scanned data sheets for the entire 1954 traverse. This directory is further broken up into subdirectories named by station number. The PDF files within them are named by date (DDMMMYYYY).

**Table 3.** Listing and Description of Files in 01-Benson-Introduction Directory
File Name (click file name to download)	Description	Size
01-Greenland-Snow-Pit-And-Stratigraphy-Introduction.pdf	Provides an outline of the data in the notebooks, maps of the location of the traverse, reference list, and a table showing proposed locations of snow pits.	5.2 MB
02-1952-stations.pdf	Lists the station number, latitude, longitude, date visited, and elevation for each pit visited in 1952.	533 KB
03-1953-stations.pdf	Lists the station number, latitude, longitude, date visited, and elevation for each pit visited in 1953.	1.2 MB
04-1954-stations.pdf	Lists the station number, latitude, longitude, date visited, and elevation for each pit visited in 1954.	1.6 MB
05-1955-stations.pdf	Lists the station number, latitude, longitude, date visited, and elevation for each pit visited in 1955.	1.5 MB
06-station-summary-matrix.pdf	Summary of the stations visited and the work done at each.	6.8 MB
07-accumulation-data-all-stations-unadjusted.pdf	Compilation of the accumulation data for each station for each year adjusted to the Fall 1954 reference horizon. Contains 9 tables and 1 summary drawing.	5.5 MB
08-accumulation-data-1955-stations-adjusted.pdf	Accumulation data for all 1955 stations adjusted to the 1955 reference horizon. Contains 8 tables and 1 summary table.	4.1 MB
09-summary-accumulation-data-adjusted.pdf	Summary of all accumulation data available for the entire traverse adjusted to the Fall 1955 reference horizon. Contains 1 summary figure.	950 KB
10-summary-average-accumulation.pdf	Summary of average accumulation at each station. Contains 1 table.	700 KB
11-integrated-RAM-hardness.pdf	Summary of the integrated ram hardness values for all stations.	9.6 MB
12-RAM-hardness-vs-temp.pdf	A table of the comparison of Ram Hardness and Temperature for 1952-1955.	6 MB

Compendium

The compendium provides snow accumulation data from 1911 to 1981 but is not at any regular temporal resolution. Dr. Benson compiled these data from a number of different sources (including his 1952-56 Greenland traverses). The compendium is made up of three ASCII text files. See Table 4.

Table 4.
File (click to download file)	Description	Size
column-descriptions.txt	Describes the columns of the data in the data files.	3 KB
greenland-snow-accumulation-1911-1981.txt	Contains the time series of the snow accumulation data.	61 KB
references.txt	Contains a list of the references for the data. Each reference in this file is numbered and corresponds to a number in the reference column of the greenland-snow-accumulation-1911-1981.txt file which indicates the source of the data.	6.5 KB

File Size and Volume

PDF files range in size from 800 KB to 136 MB. The total volume of the digitized collection is 2.8 GB.

Sample Data File

Figure 2. Example of a digitized data sheet from Dr. Benson's notebooks for Station 10 for 29 May 1954.

3. Data Access

The digitally scanned notebooks and the compendium are available via FTP. Hard copy notebooks are available for on-site use only, by appointment (library@nsidc.org).

4. References and Related Publications

Benson, C.S. 1962. Stratigraphic Studies in the Snow and Firn of the Greenland Ice Sheet, CRREL Research Report 70.

Brewster, K. N. 2001.Interview of Carl S. Benson by Karen Nichols Brewster. Ohio State University Knowledge Bank. https://kb.osu.edu/dspace/handle/1811/6050 (accessed 1/23/13).

Ragle, R.H. and T. C. Davis. 1962. South Greenland Traverses, Journal of Glaciology, Vol. 4, p. 129-131.

5. Contacts

Investigator

Carl S. Benson

Technical Contact

NSIDC User Services
National Snow and Ice Data Center
CIRES, 449 UCB
University of Colorado
Boulder, CO 80309-0449 USA
phone: +1 303.492.6199
fax: +1 303.492.2468
form: Contact NSIDC User Services
e-mail: nsidc@nsidc.org

Acknowledgements

These notebooks were digitized by NSIDC's analog archivist, Allaina Wallace; volunteer, Anna Reznik; and work study students.

6. Document Information

Document Author

A. Windnagel

Document Creation Date

January 2013

Document URL

http://nsidc.org/data/docs/noaa/g10004-greenland-snow-pit/

Service Interruption

National Snow and Ice Data Center