CO₂ reconstruction for the Miocene Climatic Optimum based on fossil plants

Margret Steinthorsdottir, Phillip E. Jardine, Willian C. Rember

The dataset contains the supporting information to stomatal-proxy and isotope based CO₂ reconstructions performed on a dataset of fossil leaves from the Miocene Climatic Optimum (MCO), ca. 16 million years ago, collected from the Clarkia Lagerstätte deposits of Idaho, USA.

MCO proxies record high temperatures of up to 7 °C above modern at moderate CO₂ levels but this cannot be replicated with existing climate models (the same models used to predict future climate change). Either previously published records underestimate CO₂ or climate models are missing important feedbacks. We reconstruct moderate CO₂ of ~450⁠ – ⁠550 ppm, implying that Earth System sensitivity must have been elevated. Ever higher climate sensitivity with rising temperatures should be very seriously considered in future predictions of climate change.

The dataset includes all information as well as code to reproduce our results. An image of the leaf material used is also included.

Citation

Margret Steinthorsdottir, Phillip E. Jardine, Willian C. Rember (2020) CO₂ reconstruction for the Miocene Climatic Optimum based on fossil plants. Dataset version 1. Bolin Centre Database. https://doi.org/10.17043/steinthorsdottir-2020-miocene-1

References

Steinthorsdottir M, Jardine PE, Rember WC. (2020). Near‐Future pCO2 during the hot Mid Miocene Climatic Optimum. Paleoceanography and Paleoclimatology. Accepted Author Manuscript. https://doi.org/10.1029/2020PA003900

Data description

The dataset includes three files:

1. Excel spreadsheet (xlsx) file with 7 tables, containing all data and modelling input parameters, as well as Monte Carlo error propagation.
2. R code for pCO₂ Monte Carlo error propagation.
3. Image of fossil leaves (Figure SI 1 in the article. pdf file).

The files are the same as in the supporting information to the article by Steinthorsdottir et al. (2020), but with revised file names. Refer to the article for further details.

Comments

Margret Stenthorsdottir is also affiliated with the Bolin Centre for Climate Research, Stockholm University.