During the last termination (from ∼18 000 years ago to ∼9000 years ago), the climate significantly warmed and the ice sheets melted. Simultaneously, atmospheric CO2 increased from ∼190 ppm to ∼260 ppm. Although this CO2 rise plays an important role in the deglacial warming, the reasons for its evolution are difficult to explain. Only box models have been used to run transient simulations of this carbon cycle transition, but by forcing the model with data constrained scenarios of the evolution of temperature, sea level, sea ice, NADW formation, Southern Ocean vertical mixing and biological carbon pump. More complex models (including GCMs) have investigated some of these mechanisms but they have only been used to try and explain LGM versus present day steady-state climates.
Bouttes N.,Paillard D.,Roche D.M.,et al. Impact of oceanic processes on the carbon cycle during the last termination[J]. Climate of the Past,2012-01-01,8(1)