Modeling the dynamics of terrestrial carbon storage since the Last Glacial Maximum

• Published in: Geophysical Research Letters
• Main Authors: Kaplan, J., Prentice, I., Knorr, W., Valdes, P.
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: 2002
• Subjects: Byrd; Taylor Dome; ice core
• Online Access: http://hdl.handle.net/11858/00-001M-0000-000E-CF25-D; http://hdl.handle.net/11858/00-001M-0000-000E-CF24-F

A dynamic global vegetation model (DGVM) was used to simulate global terrestrial carbon storage and stable carbon isotope composition changes for the last 21000 years. A paleoclimate scenario was provided by interpolation of coupled AGCM/mixed- layer ocean model experiments; [CO 2 ](atm) data were obtained from the Byrd and Taylor Dome ice core records. According to the model results, terrestrial carbon storage at the Last Glacial Maximum (LGM, 21 ka) was 821 Pg C less than today. The modeled isotopic composition (delta(13)C) of total terrestrial carbon at LGM was enriched by 1.5parts per thousand compared to present. During the deglaciation (17-9 ka), vegetation expanded rapidly into formerly glaciated areas and carbon storage correspondingly increased. Increasing NPP sustained a continuing increase in terrestrial carbon storage through the Holocene. These results do not support the published hypothesis that terrestrial CO 2 outgassing drove the ca. 20 ppm increase in [CO 2 ](atm) after 8 ka. They are consistent with an alternative explanation based on the oceanic CaCO 3 compensation response to the extraction of carbon from the atmosphere-ocean system during the deglaciation.