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Data Set ID:

Methyl Chloride Measurements from the Siple Dome A Deep Core, Antarctica, Version 1

This data set is an analysis of methyl chloride concentration measured in air extracted from ice core samples from the Siple Dome A deep core in West Antarctica. In total, forty six (46) ice samples, approximately 10-15 cm in length, were analyzed in this study. Data are available in Microsoft Excel format and are available via FTP.

Geographic Coverage

Spatial Coverage:
  • N: -81.66, S: -81.66, E: -148.82, W: -148.82

Spatial Resolution: Not Specified
Temporal Coverage:
  • 1 November 2004 to 31 May 2007
Temporal Resolution: Not specified
  • Snow/Ice
  • Snow/Ice > Snow/Ice Chemistry
Platform(s) Not specified
Data Format(s):
  • Microsoft Excel
Version: V1
Data Contributor(s): Eric Saltzman, Murat Aydin, Margaret Williams

Data Citation

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.

Saltzman, E., M. Aydin, and M. Williams. 2008. Methyl Chloride Measurements from the Siple Dome A Deep Core, Antarctica, Version 1. [Indicate subset used]. Boulder, Colorado USA. NSIDC: National Snow and Ice Data Center. doi: [Date Accessed].

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Detailed Data Description


Microsoft Excel format

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File Naming Convention

Files are named according to the following convention:


Where SDMA = Siple Dome A Core

Where MeCl = methyl chloride

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Approximately 31 kilobytes (KB)

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Spatial Coverage

Southernmost Latitude: 81.66 South 
Northernmost Latitude: 81.66 South 
Westernmost Longitude:148.82 West 
Easternmost Longitude: 148.82 West

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Temporal Coverage

November 2004 to May 2007

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Parameter or Variable

Parameters include: Methyl chloride concentration (ppt)

Sample Data Record

The worksheet has 6 columns and 48 rows. Data reported to two decimal places for all columns except error measurements (in the last column) which are reported to one decimal place.

gas age (yr) gas age (kyr) Top depth (m) Bottom depth (m) MeCl (ppt) error
130.00 0.13 61.27 61.47 630.00 4.7
259.00 0.26 75.88 76.08 577.00 6.4
342.00 0.34 84.91 85.11 471.90 5.4
387.00 0.39 90.19 90.39 532.50 6.3
490.00 0.49 100.14 100.34 512.50 5.6
785.62 0.79 130.36 130.56 646.05 11.7
1135.21 1.14 159.80 160.00 494.57 9.0
1481.22 1.48 189.80 190.00 590.05 9.2
1864.62 1.86 219.80 220.00 535.43 9.3
2268.04 2.27 249.80 250.00 496.28 18.9
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Software and Tools

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Data Acquisition and Processing

Data Acquisition Methods

The air trapped in ice was released using a dry extraction method involving mechanical shredding of the ice core under vacuum. Gas samples were analyzed by gas chromatography with high resolution mass spectrometry and quantified using an isotope dilution method. Methyl chloride was measured in 46 ice core samples, unevenly spaced in time, with a bias toward the glacial/interglacial transition and Holocene.

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Derivation Techniques and Algorithms

Error Sources

Error measurements (in the last column of the worksheet) are reported to one decimal place.

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Sensor or Instrument Description

Gas chromatograph.

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References and Related Publications

Contacts and Acknowledgments

Eric Saltzman 
3325 Croul Hall
Department of Earth System Science
University of California, Irvine 
Irvine, California 92697 USA

Murat Aydin 
3325 Croul Hall
Department of Earth System Science
University of California, Irvine 
Irvine, California 92697 USA

Margaret Williams 
NASA AMES Research Center 
Moffett Field, California 94035-1000 USA


This research was supported by National Science Foundation (NSF) Office of Polar Programs (OPP) grant 0636953 awarded to E. Saltzman.

Document Information

Document Creation Date

October 2008

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