The climate of the Earth has evolved through time, and changes driven by carbon dioxide (CO2) have occurred through periods in the planet’s history when aspects of the environment were different than today. Conditions such as solar insolation, the concentration of atmospheric CO2, and the temperature at the Earth’s surface have varied greatly over time. Each of these aspects can have a profound effect on climate feedbacks and the resulting changes in mean surface temperature.

Researchers have used a three-dimensional climate system model to better understand the climate effects of increasing CO2 over a range of solar inputs that correspond to our current understanding of paleo, present, and future Earth scenarios. The results highlight how climate sensitivity to changing CO2 varies along with the amount of solar energy received by the Earth, the starting concentration of CO2, and the mean temperature of the planet.

The study, “Evaluating Climate Sensitivity to CO2 Across Earth’s History” was published in JGR Atmospheres. The work was supported through NASA’s Habitable Worlds Program. The NASA Astrobiology Program provides resources for Habitable Worlds and other Research and Analysis programs within the NASA Science Mission Directorate (SMD) that solicit proposals relevant to astrobiology research.