ALE-GAGE-AGAGE Network Data Access

Data Availability: Data are available online for all 3 experiments, the Atmospheric Lifetime Experiment (ALE), the Global Atmospheric Gases Experiment (GAGE), and the Advanced GAGE (AGAGE), at the Carbon Dioxide Information and Analysis Center (CDIAC) at the U.S. Department of Energy, Oak Ridge National Laboratory.

Access the Databases

The entire ALE/GAGE/AGAGE data base comprising every calibrated measurement including pollution events from June 1978 to 2001 is archived at the Carbon Dioxide Information and Analysis Center (CDIAC) at the U.S. Department of Energy, Oak Ridge National Laboratory.

To access the data via ftp, click on the following link:
Access the ALE data
Access the GAGE data
Access the AGAGE data

Station Locations

The current station locations are:

• Cape Grim, Tasmania
• Cape Matatula, American Samoa
• Ragged Point, Barbados
• Mace Head, Ireland
• Trinidad Head, California

Stations also previously existed at Cape Meares, Oregon, and Adrigole, Ireland. The current Mace Head station replaced the Adrigole station and the station at Trinidad Head replaced the Cape Meares station.

Station Measurement Information

Individual measurements (generally made 4 times daily at each site for ALE, 12 times daily at each site for GAGE, and more than 30 times daily at each site for AGAGE) and monthly summary averages are provided for each site.

All ALE and GAGE data have been recalculated according to the current AGAGE calibration standards, thus creating a unified ALE/GAGE/AGAGE data set based upon the same standards.

All ALE/GAGE/AGAGE data presented here are reported in the SIO-1998 calibration scale (Prinn et al., 2000).

Data Products

In the ALE/GAGE/AGAGE global network program, continuous high frequency gas chromatographic measurements of two biogenic/anthropogenic gases (methane, CH₄; nitrous oxide, N₂O) and six anthropogenic gases (chlorofluorocarbons CFCl₃, CF₂Cl₂, and CF₂ClCFCl₂; methyl chloroform, CH₃CCl₃; chloroform, CHCl₃; and carbon tetrachloride, CCl₄) are carried out at five globally distributed sites.

Additional important species (H₂, CO, HFC-134a, HCFC-141b, and HCFC-142b) have been added at select sites in recent years.

The program, which began in 1978, is divided into three parts associated with three changes in instrumentation: the Atmospheric Lifetime Experiment (ALE), which used Hewlett Packard HP5840 gas chromatographs; the Global Atmospheric Gases Experiment (GAGE), which used HP5880 gas chromatographs; and the present Advanced GAGE (AGAGE). AGAGE uses two types of instruments: a gas chromatograph with multiple detectors (GC-MD), and a gas chromatograph with mass spectrometric analysis (GC-MS). The GC-MD is a new fully automated system produced at the Scripps Institution of Oceanography containing a custom-designed sample module and HP5890 and Carle Instruments gas chromatographic components. The GC-MS is a fully automated system produced at the University of Bristol and comprised of an adsorption-desorption pre-concentration module and HP5973 gas chromatographic and mass spectrometric module.