by Patricia Cadule
We have developed a
Climate-Carbon coupled model based on the IPSL OAGCM and on two biogeochemical
models, ORCHIDEE for the continent and PISCES for the ocean, to investigate the
coupling between climate change and the global carbon cycle. We have performed
four climate-carbon simulations over the 1860-2100 period in which atmospheric
CO2 is interactively calculated. They are :
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A control coupled
simulation with no anthropogenic emissions.
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A coupled
simulation with anthropogenic emissions.
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A coupled
simulation with anthropogenic emissions including non-CO2 greenhouse
and sulfate aerosols.
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An uncoupled
carbon simulation with the same anthropogenic emissions as second simulation
but for which atmospheric CO2 change has no impact on climate.
Compared to the first IPSL
Climate-Carbon coupled model [Dufresne,
et al., 2002], the simple carbon models have been replaced by IPSL advanced
ocean and land biogeochemical models, respectively PISCES and ORCHIDEE. CO2
is transported in the atmosphere and compared with observations. Comparison
with satellite data is also done. We then analyze the coupled and uncoupled
simulations, highlight the importance of the climate change both on the oceanic
and biosphere sink and estimate the climate-carbon feedback. The results are
also compared to the outputs of other models participating in the C4MIP
inter-comparison project. Finally, off-line simulations are carried out to
perform sensitivity tests (fire, dynamics of land and ocean ecosystems, soil
respiration) in order to identify the key processes which govern the simulated
response.
Link to Abstract
Link to Slides