Future expansion of agriculture and pasture acts toamplify atmospheric CO2 levels in response to fossilfuel and land-use change emissions

Vincent Gitz and Philippe Ciais ()
Additional contact information
Philippe Ciais: LSCE - Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] - UVSQ - Université de Versailles Saint-Quentin-en-Yvelines - INSU - CNRS - Institut national des sciences de l'Univers - Université Paris-Saclay - CNRS - Centre National de la Recherche Scientifique - DRF (CEA) - Direction de Recherche Fondamentale (CEA) - CEA - Commissariat à l'énergie atomique et aux énergies alternatives, ICOS-ATC - ICOS-ATC - LSCE - Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] - UVSQ - Université de Versailles Saint-Quentin-en-Yvelines - INSU - CNRS - Institut national des sciences de l'Univers - Université Paris-Saclay - CNRS - Centre National de la Recherche Scientifique - DRF (CEA) - Direction de Recherche Fondamentale (CEA) - CEA - Commissariat à l'énergie atomique et aux énergies alternatives

Post-Print from HAL

Abstract: The expansion of crop and pastures to the detriment of forests results into an increase in atmospheric CO2. A first obvious cause is the loss of forest biomass and soil carbon during and after conversion. A second, generally ignored cause, is the reduction of the residence time of carbon when for example forests or grasslands are converted to cultivated land. This decreases the sink capacity of the global terrestrial biosphere, and thereby may amplify the atmospheric CO2 rise due to fossil and land-use carbon release. For the IPCC-A2 future scenario, characterized by high fossil and high land-use emissions, we show that the land-use amplifier effect adds 61 ppm extra CO2 in the atmosphere by 2100 as compared to former treatment of land-use processes in carbon models. Investigating the individual contribution of each of the 6 land-use transitions (forest - crop, forest - pasture, grassland -crop) to the amplifier effect indicates that the clearing of forest and grasslands to arable lands explains most of the CO2 amplification. The amplification effect is 50% higher than in a previous analysis by the same authors which did not consider neither the deforestation to pastures nor the ploughing of grasslands. Such an amplificationeffect is further examined in sensitivity tests where the net primary productivity is considered independant of atmospheric CO2. We also show that land-use changes which have already occurred in the recent past have a strong inertia at releasingCO2, and will contribute to about 1/3 of the amplification effect by 2100. These results suggest that there is an additionnal atmospheric benefit of preserving pristine ecosystems with high turnover times.

Keywords: land use; atmospheric CO2; fossil fuel (search for similar items in EconPapers)
Date: 2004
Note: View the original document on HAL open archive server: https://shs.hal.science/halshs-00009828v1
References: Add references at CitEc
Citations: View citations in EconPapers (2)

Published in Climatic Change, 2004, 67 (2-3), pp.161-184. ⟨10.1007/s10584-004-0065-5⟩

Downloads: (external link)
https://shs.hal.science/halshs-00009828v1/document (application/pdf)

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:hal:journl:halshs-00009828

DOI: 10.1007/s10584-004-0065-5

Access Statistics for this paper

More papers in Post-Print from HAL
Bibliographic data for series maintained by CCSD ().