Comparing transient, accelerated, and equilibrium simulations of the last 30 000 years with the GENIE-1 model
International audience We examine several aspects of the ocean-atmosphere system over the last 30 000 years, by carrying out simulations with prescribed ice-sheets, atmospheric CO 2 concentration, and orbital parameters. We use the GENIE-1 model with a geostrophic ocean, dynamic sea-ice, an energy b...
Main Authors: | , , , |
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Other Authors: | , , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
HAL CCSD
2006
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Subjects: | |
Online Access: | https://hal.science/hal-00298130 https://hal.science/hal-00298130/document https://hal.science/hal-00298130/file/cpd-2-267-2006.pdf |
Summary: | International audience We examine several aspects of the ocean-atmosphere system over the last 30 000 years, by carrying out simulations with prescribed ice-sheets, atmospheric CO 2 concentration, and orbital parameters. We use the GENIE-1 model with a geostrophic ocean, dynamic sea-ice, an energy balance atmosphere, and a land-surface scheme with fixed vegetation. A transient simulation, with boundary conditions derived from ice-core records and ice-sheet reconstructions, is compared with equilibrium snapshot simulations, including the Last Glacial Maximum (21 000 years before present; 21 kyrBP), mid-Holocene (6 kyrBP) and pre-industrial. The equilibrium snapshot surface temperatures are all very similar to their corresponding time period in the transient simulation, suggesting that in the last 30 000 years, the ocean-atmosphere system has been close to equilibrium with its boundary conditions. We investigate the method of accelerating the boundary conditions of a transient simulation and find that the Southern Ocean is the region most affected by the acceleration. The Northern Hemisphere, even with a factor of 10 acceleration, is relatively unaffected. |
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