Atmospheric O2:N2 ratios measured over time, together with the mixing ratio of atmospheric carbon dioxide, are the most direct means available for scientifically documenting the global sources and sinks of CO2, the dominant anthropogenic greenhouse gas. This then is primary data informing the assessment reports issued by the Intergovernmental Panel on Climate Change (IPCC) on behalf of the climate community and which serve to advise WMO (World Meteorological Organization) and UNEP (United Nations Environmental Programme). These reports in turn are the basis for many national and international responses to climate change science, mitigation and adaptation strategies.
Since 1989, Scripps investigators, in conjunction with the CO2 global sampling network (initiated by CD Keeling), have sustained a regular (semi-weekly) sampling and measurement program over ~ 9 global stations to document changes in the global atmospheric O2/N2 ratio. Additional evaluation of another atmospheric mixing ratio (Ar/N2) will be sought to provide insight into the global ocean-atmosphere heat exchange.
