On the variability of oxygen anomaly in tropospheric CO2

We present a recent effort for measuring the triple oxygen isotope composition of CO2 in the troposphere. The analysis is based on a newly developed technique that utilizes platinum as a catalyst to catalyze the isotope exchange between CO2 and O2 (Mahata et al., Analytical Chemistry, 2013). The method provides a simple, rapid, clean, and robust way for measuring the triple oxygen isotope ratio of carbon dioxide with high precision. The currently achieved precision is better than 10 per meg (0.01 per mil). With this highly reproducible method, we have successfully measured the triple oxygen isotope composition of near surface and mid-tropospheric CO2. These different sources of CO2 show strong spatiotemporal variability. Results and implications will be presented and discussed.