Past Climate Conditions Anticipates Sea Level From Ice Sheets and CO2 Stabilization

Science, November 6
The Pliocene Epoch (3-4 million years ago) is our best analogue for current rates of climate change. During this period, CO2 concentrations peaked at 427 ppm; and sea-level was about 17 m higher than today, implying a near-to-complete loss of the Greenland and West Antarctic Ice Sheets, as well as substantial portions of the East Antarctic Ice Sheet. These paleo-climate records may also show the time it would take for CO2 concentrations to drop below Pliocene levels and return to preindustrial levels absent human intervention, such as negative emissions technologies: with concentrations similar to low-emissions scenarios, peaking below 450 ppm, it took hundreds to thousands of years for concentrations to return to preindustrial levels.  At higher peak CO2 concentrations (above 600 ppm), a return to pre-industrial levels may take more than 500 000 years.

Compiled by Amy Imdieke.

By Amy Imdieke, Global Outreach Director, and Pam Pearson, Director of ICCI.
Published Nov. 17, 2020      Updated Jul. 12, 2022 3:22 pm