A ~1000-year 13C Suess correction model for the study of past ecosystems

Inferences about how an ecosystem has changed through time often rely on longitudinal records of species characteristics or niche parameters, and stable isotope analysis is a common tool employed to study changes in an organism’s niche. One of the most frequently used stable isotope measures is δ13C, a ratio of 13C to 12C. However, applying δ13C to historical samples comes with some methodological hurdles. One such hurdle is correcting for the 13C Suess effect or the change in atmospheric δ13C due to increased anthropogenic CO2 emissions. The change in the amount of carbon isotopes in the atmosphere through time can confound the study of historical shifts in species characteristics. No standard way of correcting for the 13C Suess effect has been suggested despite this problem. Here, I propose a standard 13C Suess correction model for the past ~1000 years using three prehistoric/historic records of atmospheric δ13C.