Triple oxygen isotope variations in natural and anthropogenic carbon dioxide

• Applicant: Professor Dr. Andreas Pack
• Subject Area: Mineralogy, Petrology and Geochemistry
• Term: from 2009 to 2014
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 106026871

We will use the oxygen triple isotope composition of gaseous CO2 of different provenance as constraint to better understand the CO2 budget in the Earth s troposphere. Different reservoirs (natural, anthropogenic) are expected to have distinctly different (17O/(18O ratios (expressed in form of the ∆17OTFL notation). The ∆17OTFL of tropospheric CO2 will be compared to ∆17O of CO2 from soil and human respiration, combustion of organic matter (fossil & modern), limekiln and blast furnace operation, respectively. Experiments will be conducted to determine the 17O/16O and 18O/16O fractionation between CO2 and H2O. The experiments will be used to study the effect of equilibration of CO2 with H2O (e.g in leaf stomata, soils, oceans) on ∆17OTFL. Results will be used to model the exchange of CO2 between bio-, tropo- and stratosphere, respectively. An integral part of this study is to establish a novel technique for the determination of ∆17OTFL of CO2 with high accuracy and precision.

• DFG Programme: Research Grants