Climate Science

Forward into the Past

See allHide authors and affiliations

Science  06 Dec 2013:
Vol. 342, Issue 6163, pp. 1149
DOI: 10.1126/science.342.6163.1149-b

It has been well established that high concentrations of atmospheric CO2 caused by anthropogenic emissions will persist for thousands of years after those emissions cease and that the consequences for climate will last even longer than that. Suggestions have been made that CO2 could be removed from the atmosphere artificially in order to speed global climate recovery, but what can be expected from such a capture scheme? MacDougall uses a climate model of intermediate complexity, employing scenarios of CO2 removal that move from the more idealized schemes used in past studies toward more realistic ones, in order to continue refining our understanding of what would be the effects of such an undertaking. He finds that by assuming a moderate value of climate sensitivity and that CO2 is removed from the atmosphere as fast as it was added once emissions cease, surface air temperatures like those of preindustrial times can be approached by the year 3000 CE in all but the most extreme emission scenarios. Other components of the climate system, such as mass of the polar ice sheets, and sea level, will take longer to recover, however. So, even if we dial back atmospheric CO2 concentrations by massive geoengineering, we will be living with the effects of fossil fuel burning for many hundreds of years, at the least.

Geophys. Res. Lett. 40, 5480 (2013).

Navigate This Article