Greenhouse Gas Monitoring Made Simple

Among the components which make up the earth’s atmosphere, carbon dioxide and methane are particularly important. Unlike any other species, these gases have three special characteristics:

1. Each is a powerful greenhouse gas. That is, each produces positive radiative forcing¹
    
2. Each exists for a long time in the atmosphere so that fluctuations in concentration are small when compared to average concentration levels. , which tends to warm the surface of the earth.
3. Each has significant anthropogenic contributions.

In addition to water vapor, these gases are key components of earth’s natural temperature control system. In fact, the radiative forcing of both of these gases is so powerful that small changes in their concentration have caused measurable increases in the surface temperature of the planet. Quoting from the Intergovernmental Panel on Climate Change (IPCC) 2007 report, “The global average surface temperature…has increased since 1861. Over the 20th century the increase has been 0.6 ± 0.2^oC.”² This increase is due, in large part, to an 85 parts-per-million (ppm) increase in carbon dioxide and a one ppm increase in methane concentration. This increase has resulted in an increase in radiative forcing of 1.94 Wm^{-2 2} . This change is huge and likely to have resulted in the largest temperature change of any century during the past 1,000 years. The concern about global warming has generated great interest in monitoring greenhouse gases both from an individual researcher as well as a monitoring network prospective.