LUCID CMIP5 experiments

The LUCID community also contributed to the fifth Coupled Model Intercomparison Project (CMIP5):

1. Integrated Assessment Model (IAM) groups provided the CMIP5 community with four representative concentration pathways (RCPs) of greenhouse gases and aerosols, and the associated land use and land cover changes through the 21st century. The set of RCP scenarios envelopes different scenarios of future land-use changes, which satisfy the demand for food, biofuels and afforestation (or reforestation) to mitigate CO2-induced climate changes. In the core set of CMIP5 simulations, Earth System models (ESMs) are driven through the 21st century by a set of RCP scenarios that include land-use changes. To isolate the effect of land-use changes on climate, six CMIP5 modeling groups performed additional LUCID-CMIP5 simulations without anthropogenic land-use changes from 2006 to 2100. The differences between simulations with and without land-use changes reveal climatic effects of LULCC on global and regional scales. The model output was post- processed into the standard CMOR format of CMIP5, and for some models made available via the Earth Grid. 
2. As an added value, results from the LUCID-CMIP5 experiments are also used in the analysis of vegetation response to climate and CO2 changes outside the framework of the LUCID project (Bathiany et al., submitted). 
   
3. The LUCID-CMIP5 analysis revealed that the effects of land-use changes on mean annual temperature in RCP8.5 and 2.6 scenarios are significant for regions with land-use changes exceeding 10%. Changes in land-surface albedo, available energy, and latent heat fluxes are small but significant for most ESMs in regions affected by land-use change (Brovkin et al., 2013). 
   These climatic effects are relatively small, as land-use changes in the RCP2.6 and RCP8.5 scenarios are small in magnitude and mainly limited to tropical and subtropical regions. Crops tend to warm climate in most areas and models (Boysen et al., tbs). 
   A causal link between LULCC forcing and the climate impact is found in some models where the presence of pastures tends to induce a local biogeophysical cooling which offsets a biogeochemical warming. Conversion to pastures thus may have a climate change mitigation potential but more detailed and idealized experiments are required. 

If any researchers seek access to the simulations conducted as part of the LUCID CMIP5 experiments, please contact Victor Brovkin at victor.brovkin@mpimet.mpg.de. These data are freely available for research purposes.