The special collection on "Climate—Carbon Interactions in the CMIP5 Earth System Models" (C4MIP) includes a series of papers which analyze results from Earth System Model (ESM) simulations performed for the fifth Coupled Modeling Intercomparison Project (CMIP5; Taylor et al., 2011), with a specific focus on the global carbon cycle. These simulations are also contributing to the Fifth Assessment Report (AR5) of the Intergovernmental Panel on Climate Change (IPCC). State-of-the-art ESMs represent global land and ocean carbon cycle-related biogeochemical processes and their interactions with the physical climate system.
The CMIP5 protocol includes historical and future simulations driven with representative concentration pathways (RCPs) of greenhouse gases. For each of the greenhouse gas RCPs, the corresponding emissions are also available. The CMIP5 protocol includes ESM simulations that are driven with either prescribed CO2 concentration or CO2 emissions. It also includes the idealized specified concentration scenario, in which the atmospheric CO2 increases at a rate of 1% per year.
The papers in this special collection include multi-model analyses for historical and future RCP scenarios, focusing on carbon cycle response to climate change, compatible emissions, feedback analysis, process-oriented model evaluation, more specific analysis such as the response of permafrost to future climate change, and the impact of land use change on terrestrial carbon cycle processes.
Pierre Friedlingstein, University of Exeter
Chris Jones, UK Met Office
Vivek Arora, Canadian Centre for Climate Modeling and Analysis