State of Environment

Indicator 11 - Atmospheric concentrations of greenhouse gas species

Index: Description | Data | Custodian evaluation | Related resources | Parameters


Indicator Definition
Measurement of air samples for values of the primary greenhouse gases (carbon
dioxide, methane and nitrous oxide) and associated species (carbon monoxide,
hydrogen and isotopes of carbon dioxide) in the Southern Hemisphere atmosphere.

Responsible organisation

organisation logo

Commonwealth Scientific and Industrial Research Organisation


No custodians.

Theme area


Indicator type

Condition Pressure

Criteria the indicator satisfies

The following 13 out of 15 criteria

1. Serve as a robust indicator of environmental change
2. Reflect a fundamental or highly-valued aspect of the environment or an important environmental issue
3. Be either national in scope or applicable to regional environmental issues of national significance
4. Provide an early warning of potential problems
5. Be capable of being monitored to provide statistically verifiable and reproducible data that shows trends over time and, preferably, apply to a broad range of environmental regions
6. Be scientifically credible
7. Be easy to understand
8. Be monitored with relative ease
9. Be cost-effective
10. Have relevance to policy and management needs
11. Contribute to monitoring of progress towards implementing commitments in nationally important environmental policies
13. Contribute to the fulfillment of reporting obligations under international agreements
15. Where possible and appropriate, be consistent and comparable with other countries� and state and territory indicators

For details of indicators, see the State of Environment Bibliography entries 16336 and 16337

Date input

Monthly measurements

Monitoring location

Geographic coverage

Rationale For Indicator Selection
Over the last century the concentration of greenhouse gases has risen in the
atmosphere. The average rise is about half that expected from human
activities, predominantly the burning of fossil fuel. Thus observations of the
concentration of these gases provides a measure of anthropogenic greenhouse
forcing in the atmosphere, and for example, monitors the effectiveness of
oceans and terrestrial biomes in removing the excess CO2.

Measurements of long-lived trace gas levels in Antarctic air generally provide
an accurate integration of global exchanges between the surface and the
atmosphere. The climate-influencing gases of main interest are gases released
as a result of human activity, as well as from (climate-driven) physical,
chemical and biological processes in both land and oceans. The Antarctic
monitoring, in concert with other global network results, exploits trace gas
ratios to identify and locate globally significant exchanges.

Design and Strategy For Indicator Monitoring Program
Spatial Scale: High latitude Southern Hemisphere air samples are collected
from AAD sites by BoM personnel at Mawson station, Casey station and Macquarie
Island, and by NOAA staff at South Pole. These complement CSIRO supervised
sites at Cape Grim, Tasmania and ~7 other globally distributed locations.

Frequency: Typical sites collect ~4 flasks of air per month for subsequent
analysis at CSIRO.

Measurement Technique: Various chemical analysis techniques (Francey et al.

Research Issues
For global trace gas monitoring, improvements are sought in network
intercalibration and in increased sampling, e.g. continuous CO2 monitoring,
vertical profiles, continental sites. More generally, improved coordination of
atmospheric composition modeling, surface flux measurements and atmospheric
transport representations are sought to serve new "multiple-constraint
modeling frameworks".


Temporal range of the available data, as described by the metadata record, is from 01-Nov-1984 .

May-1984 to December-2006
Number of data points

To view or download any of the data, you must be logged in

Data quality, interpretation and analysis of indicator data

Data usage constraints

' This data set conforms to the PICCCBY Attribution License ( Please follow instructions listed in the citation reference provided at when using these data. '

Data access constraints

' See the URL below for State of the Environment indicator 11 for access to these data. A copy of the raw data are also available for download from the URL given below. '

Custodian evaluation

8 May 2002

The three gases carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) together contribute around 70% of the anthropogenic greenhouse forcing. All three gases have lifetimes much longer than interhemispheric mixing and the major source and sink regions are in the northern hemisphere. Thus detection of coherent changes at high southern latitudes is an unambiguous indication of global change. The following report describes data from the CSIRO network including Mawson, Casey, Macquarie Island (also Cape Grim, South Pole). Since 1999, there has been has been a dramatic slowdown at all southern sites in the annual growth of methane that is unprecedented in the last two decades of monitoring. The growth rate is actually negative in 2001/2002, and remains zero or less over the last three years. The annual average level in 2001 was 1706 ppb. Over the last 8 years, global CO2 has increased at 1.75 ppm/year, significantly above the 1.5 ppm/year of the previous decade. Record growth rates in 1997/98 attributed in part to huge tropical biomass burning, contribute to this increased long-term growth. The annual average level in 2001 was 368.3 ppm. The N2O trends share many features with CO2. Over the last 8 years the increase has been 0.8 ppb/year with higher growth around the 1997-1998 period. The annual average level in 2001 was 316 ppb.

11 Nov 2002

Condition scale - 0 - cannot be set
1 - the environment degraded to the point where rehabilitation is impossible
0 1 2 3 4 5 6 7
7 - the environment is pristine, in perfect condition, no anthropogenic influences
Pressure scale - 6
1 - undetectable external pressure on the environment
0 1 2 3 4 5 6 7
7 - extreme external pressure on the environment, degradation accelerating
State of Knowledge scale - 4 - Fair
1 - Poor
0 1 2 3 4 5 6 7
7 - Excellent

For definitions of the Scale categories, consult the Explanation of the Status Categories

Related resources

Metadata SOE_greenhouse_gas - Air sampling for greenhouse gas concentrations and associated species
Project 98 - Antarctic and Southern Ocean atmospheric aerosol study
Project 1133 - The consequences of elevated atmospheric carbon dioxide concentrations on inorganic carbon acquisition and photosynthetic performance of Antarctic macroalgae
Project 2282 - Atmospheric sulfur species at high southern latitudes
Scientific Bibliography 17284 - Francey, Roger J., Paul (L.P.) Steele, Ray L. Langenfelds, Marco Lucarelli, Colin E. Allison, David J. Beardsmore, Scott A. Coram, Nada Derek, Fred de Silva, David M. Etheridge, Paul J. Fraser, Reg J. Henry, Brian Turner and Emily D. Welch (1996). Global Atmospheric Sampling Laboratory (GASLAB) (1993) supporting and extending the Cape Grim trace gas programs, Baseline Atmospheric Program (Australia) 1993. (eds. R.J.Francey, A.L.Dick and N.Derek) Bureau of Meteorology and CSIRO Division of Atmospheric Research, Melbourne, pp 8-29.
Scientific Bibliography 17285 - Francey, R.J., P.J. Rayner and C.E. Allison (2001) Constraining the global carbon budget from global to regional scales - the measurement challenge. In: Global Biogeochemical Cycles in the Climate System, Academic Press, New York, p245-252.
SOE Indicator 1 - Monthly mean air temperatures at Australian Antarctic Stations
SOE Indicator 2 - Highest monthly air temperatures at Australian Antarctic Stations
SOE Indicator 3 - Lowest monthly air temperatures at Australian Antarctic Stations
SOE Indicator 4 - Monthly mean lower stratospheric temperatures above Australian Antarctic Stations
SOE Indicator 12 - Noctilucent cloud observations at Davis
SOE Indicator 14 - Midwinter atmospheric temperature at altitude 87km


The properties link can be used to view details of the parameters measured for this indicator.

Parameter Name Unit of measure Properties
Atmospheric Carbon Dioxide - C13 isotope concentration per mil Properties
Atmospheric Carbon Dioxide concentration ppm Properties
Atmospheric Carbon Monoxide concentration ppb Properties
Atmospheric Hydrogen concentration ppb Properties
Atmospheric methane concentration ppb Properties
Atmospheric nitrous oxide concentration ppb Properties

The following parameters and/or sensor notes are from the metadata record.





Related URLs
Citation reference for this metadata record and dataset
Download page for Australian Antarctic Data Centre
Download point for the raw data