Articles | Volume 14, issue 2
Research article
23 Feb 2018
Research article |  | 23 Feb 2018

Sensitivity of the Eocene climate to CO2 and orbital variability

John S. Keery, Philip B. Holden, and Neil R. Edwards

Model code and software

PLASIM--GENIE v1.0: a new intermediate complexity AOGCM P. B. Holden, N. R. Edwards, K. Fraedrich, E. Kirk, F. Lunkeit, and X. Zhu

Short summary
In the Eocene (~ 55 million years ago), the Earth had high levels of atmospheric CO2, so studies of the Eocene can provide insights into the likely effects of present-day fossil fuel burning. We ran a low-resolution but very fast climate model with 50 combinations of CO2 and orbital parameters, and an Eocene layout of the oceans and continents. Climatic effects of CO2 are dominant but precession and obliquity strongly influence monsoon rainfall and ocean–land temperature contrasts, respectively.