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| | 3 | == Context == |
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| | 5 | The terrestrial biosphere is a significant source of reactive chemical compounds, such as isoprene, monoterpenes..., or other volatile organic compounds emitted by plants and mainly leaves, or nitrogen oxides emitted by nitrification and denitrification soil processes. Those compounds play a key role in the atmospheric chemical composition and especially in the ozone cycle or aerosol formation. Moreover, distribution and growth of terrestrial ecosystems is a strong driver of the deposition, and therefore the loss, of atmospheric chemical compounds at the surface. On the other hand, strong and persistent atmospheric concentrations of compounds such as ozone, nitrogen oxides or sulfur doixide can lead to leaf necrosis, decrease in photosynthetic activity and alter plan growth. |
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| | 7 | There are therefore strong interactions between the terrestrial biosphere and the atmospheric chemical composition, that have to be considered when investigating the evolution of the Earth System. This objective of the coupling between the vegetation model ORCHIDEE and the chemistry-transport model LMDzINCA is to take into account those interactions and add consistency in the IPSL Earth System Model when related to the description of vegetation growth and distribution: |
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| | 9 | * Biogenic emissions of reactive compounds (VOCs and NOx) calculated by ORCHIDEE sent to INCA, instead of having an input emission files |
| | 10 | * Distribution of vegetation types prescribed or calculated by ORCHIDEE sent to INCA, corresponding to the time period of interest, instead of having one vegetation distribution file only, read as input file by INCA for any scenario |
| | 11 | * In the purpose of investigating the impact of atmospheric chemical composition on plant growth and distribution: atmospheric concentrations of ozone (in a first step) and other chemical compounds (longer-term) calculated by INCA to be sent to ORCHIDEE where the impact on plant functional types will be calculated (see the PhD work carried out by Thomas Verbeke, LSCE, this page). |
