Alkanes in firn air samples, Antarctica and Greenland

Summary

This data set contains ethane, propane, and n-butane measurements in firn air from the South Pole and the West Antarctic Ice Sheet (WAIS) Divide in Antarctica, and from Summit, Greenland. The WAIS Divide and South Pole samples were collected in December to January of of 2005/06 and 2008/09, respectively. The Summit firn was sampled in the summer of 2006. Analyses were conducted on a gas chromatography - mass spectrometry (GC-MS) system at the University of California, Irvine. Measurements and the associated uncertainties are reported as dry air molar mixing ratios in part per trillion (ppt). The reported measurements for each sampling depth represent a mean of multiple measurements on more than one flask in most cases.

Data are available via FTP in Microsoft Excel (.xls) format.

Citing These Data

We kindly request that you cite the use of this data set in a publication using the following citation. For more information, see our Use and Copyright Web page.

The following example shows how to cite the use of this data set in a publication. List the principal investigators, year of data set release, data set title, publisher: NSIDC, and digital media.

Aydin, M and E. Saltzman. 2011. Alkanes in firn air samples, Antarctica and Greenland. Boulder, Colorado USA: National Snow and Ice Data Center. http://dx.doi.org/10.7265/N5X9287C.

Overview Table

Category Description
Data format

Microsoft Excel (.xls)

Spatial coverage and resolution

South Pole, Antarctica
Latitude: 90°S
Longitude: 0°E

WAIS Divide Ice Core Site, Antarctica
Latitude: 79.47°S
Longitude: 112.09°E

Summit Ice Core Site, Greenland
Latitude: 72.5833°N
Longitude: 38.3833°W

Temporal coverage December to January 2005/06
December to January, 2008/09
Summer 2006 (Northern Hemisphere)
File naming convention UCI_FirnAirData_LightAlkanes.xls
File size 19 KB
Parameters ethane
propane
n-butane
Procedures for obtaining data FTP

Table of Contents

  1. Contacts and Acknowledgments
  2. Detailed Data Description
  3. Data Access and Tools
  4. Data Acquisition and Processing
  5. References and Related Publications
  6. Document Information

1. Contacts and Acknowledgments

Investigators

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

Dr. Eric Saltzman
University of California, Irvine
3325 Croul Hall
Irvine, California 92697
USA

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

This research was funded by the National Science Foundation (NSF) Office of Polar Programs (OPP) grant number 0739598.

2. Detailed Data Description

Format

This data set is provided in Microsoft Excel (.xls) format.

File and Directory Structure

Data are available on the FTP site in the ftp://sidads.colorado.edu/pub/DATASETS/AGDC/nsidc0504_aydin_V01/ directory. The data set consists of one file, UCI_FirnAirData_LightAlkanes.xls.

File Size

The data set is 19 KB.

Spatial and Temporal Coverage

Measurements were taken from firn air from three locations:

Table 1. Site Locations and Dates of Sample Collection
Site Name Location Dates of Firn Sample Collection

South Pole, Antarctica

Latitude: 90°S
Longitude: 0°E

December 2008 to January 2009

WAIS Divide Ice Core Site, Antarctica

Latitude: 79.47°S
Longitude: 112.09°E

December 2005 to January 2006

Summit Ice Core Site, Greenland

Latitude: 72.5833°N
Longitude: 38.3833°W

Summer 2006 (Northern Hemisphere)

 

Parameter or Variable

This data set contains ethane, propane, and n-butane measurements from firn air, reported as dry air molar mixing ratios in part per trillion (ppt).

Parameter Description

Table 2.Parameter Description
Parameter Description

depth (m)

Sample depth, in meters below surface

ethane (ppt)
propane (ppt)
n-butane (ppt)

Gas concentration measurement, reported as dry air molar mixing ratios in part per trillion (ppt)

2 s.e. (ppt)

Standard error range of the data, reported as dry air molar mixing ratios in part per trillion (ppt)

 

Sample Data Record

This sample data record shows the first three records for propane data.

Firn air propane data
South Pole, Antarctica WAIS-D, Antarctica Summit, Greenland
depth (m) propane (ppt) 2 s.e. (ppt) depth (m) propane (ppt) 2 s.e. (ppt) depth (m) propane (ppt) 2 s.e. (ppt)
0 6.3 1.7 0 11.3 2.0 0 102.7 14.2
10 22.0 0.6 14.99 25.1 6.2 10.01 459.4 30.8
17 29.9 2.0 20.53 28.8 6.2 15.05 469.7 25


3. Data Access and Tools

Data Access

Data are available via FTP.

Volume

Total volume of the data set is 19 KB.

Software and Tools

Data are accessible using Microsoft Excel.

Related Data Collections

Related Web Sites

4. Data Acquisition and Processing

Theory of Measurements

Hydrocarbons such as methane, ethane, and n-butane, are released from fossil fuel burning as well as from natural sources. By measuring the concentration of hydrocarbons from firn air samples, researchers can determine historical atmospheric concentrations of these chemicals, dating back multiple decades. These data may therefore be useful for quantifying historical fossil fuel emissions.

Sensor or Instrument Description

Samples were measured in a laboratory at the University of California, Irvine, on a gas chromatography-mass spectrometer (GC-MS) designed for trace gas analysis.

Data Acquisition Methods

Researchers filled flasks from firn air samples using established methods, cited in Battle, et. al. 1996.

5. References and Related Publications

Aydin, M., K. R. Verhulst, E. S. Saltzman, M. O. Battle, S. A. Montzka, D. R. Blake, Q. Tang, and M. J. Prather. 2011. Recent Decreases in Fossil Fuel Emissions of Ethane and Methane Derived from Firn Air, Nature, 476, 198-201, doi:10.1038/nature10352.

Aydin, M., M. B. Williams, and E. S. Saltzman. 2007. Feasibility of Reconstructing Paleoatmospheric Records of Selected Alkanes, Methyl Halides, and Sulfur Gases from Greenland Ice Cores. Journal of Geophysical Research. 112, D07312, doi:10.1029/2006JD008027.

Battle, M. et al. 1996. Atmospheric Gas Concentrations over the Past Century Measured in Air from Firn at the South Pole. Nature 383. 231-235.

6. Document Information

Acronyms

The following acronyms are used in this document.

Table 3. Acronyms and Abbreviations
Acronym Description
AGDC Antarctic Glaciological Data Center
FTP File Transfer Protocol
NSIDC National Snow and Ice Data Center
URL Uniform Resource Locator
WAIS West Antarctic Ice Sheet Divide

Document Creation Date

14 December 2011

Document URL

http://nsidc.org/data/docs/agdc/nsidc0504-aydin/index.html