Atmospheric Observing Systems, Inc. has developed a new Airborne Analyzer System for autonomous observations of dry mole fraction of Carbon Dioxide from light aircraft. AOS presents an archive of more than 100 vertical profiles to prove its performance. The observed site was Ameriflux (40.734N, 104.301W) in northern Colorado.

The present study made an attempt to analyse the extent of natural and anthropogenic carbon in the atmosphere and oceans particularly with reference to Indian Ocean as major human clusters are responsible for climate change. The study also probes into the spatial patterns and temporal variation using the time series data collected from secondary sources.

We evaluate the impact on modeled atmospheric CO₂ concentrations of explicitly representing the tropospheric CO₂ source from reduced carbon oxidation. We also calculate the bias in inverse flux estimates that results from omitting this influence.

We have conducted long-term regular monitoring of vertical profiles of ¹³C/¹²C ratio of atmospheric CO₂ over three sites in Siberia and a site in Japan. Time-series and seasonality of the ¹³C/¹²C ratio at each altitude levels at the four site were examined. Apparent isotopic signature was calculated from the relationship between CO₂ mixing ratio and the ¹³C/¹²C ratio in individual vertical profiles.

Three years of quasi-continuous atmospheric ¹⁴CO₂ observations in Heidelberg (Germany) have been used together with continuous CO measurements to determine the CO/fossil fuel CO₂ ratio in a regional polluted area. Comparison with bottom-up information on fossil fuel CO₂ and CO emissions for the respective catchment area shows that large discrepancies (up to 60%) between inventory data and observations exist. Therefore both, a lot of care and reliable emissions inventory data are necessary if CO shall be used as a quantitative surrogate for fossil fuel CO₂.