Quantifying the effect of vegetation dynamics on the climate of the Last Glacial Maximum
International audience The importance of the biogeophysical atmosphere-vegetation feedback in comparison with the radiative effect of lower atmospheric CO 2 concentrations and the presence of ice sheets at the last glacial maximum (LGM) is investigated with the climate system model CLIMBER-2. Equili...
Main Authors: | , , , |
---|---|
Other Authors: | , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
HAL CCSD
2005
|
Subjects: | |
Online Access: | https://hal.archives-ouvertes.fr/hal-00298109 https://hal.archives-ouvertes.fr/hal-00298109/document https://hal.archives-ouvertes.fr/hal-00298109/file/cpd-1-1-2005.pdf |
Summary: | International audience The importance of the biogeophysical atmosphere-vegetation feedback in comparison with the radiative effect of lower atmospheric CO 2 concentrations and the presence of ice sheets at the last glacial maximum (LGM) is investigated with the climate system model CLIMBER-2. Equilibrium experiments reveal that most of the global cooling at the LGM (?5.1°C) relative to present-day conditions is caused by the introduction of ice sheets into the model (?3.0°C, 59%), followed by the effect of lower atmospheric CO 2 levels at the LGM (?1.5°C, 29%). The biogeophysical effects of changes in vegetation cover are found to cool the LGM climate by 0.6°C (12%). They are most pronounced in the northern high latitudes, where the taiga-tundra feedback causes annually averaged temperature changes of up to ?2°C, while the radiative effect of lower atmospheric CO 2 in this region only produces a cooling of 1.5°C. Hence, in this region, the temperature changes caused by vegetation dynamics at the LGM exceed the cooling due to lower atmospheric CO 2 concentrations. |
---|