FaIR v1.6.2 calibrated and constrained parameter set

These .json files provides the 2237 ensemble members that are used to run the FaIR simple climate model in the IPCC's Sixth Assessment Report contributions to Working Group 1 and Working Group 3.

v1.1 of this dataset includes two versions of the files:

• the original full parameter set `fair-1.6.2-wg3-params.json` as in v1.0
• reduced file size versions `fair-1.6.2-wg3-params-slim.json` and `fair-1.6.2-wg3-params-common.json` where only the parameters that vary between ensemble members are included in the former and everything else is in the latter. This is optimised for running the Working Group 3 climate assessment.

Drawn from an initial prior ensemble of 1 million, the following constraints are placed upon the results:

• representation of observed warming from 1850-2019, within observational uncertainty
• representation of observed ocean heat content change 1971-2018, within observational uncertainty
• reproduction of near-present day atmospheric concentrations of CO2 from the carbon cycle
• airborne fraction of CO2 with a distribution similar to the assessed range of Chapter 5, IPCC Working Group 1 AR6
• equilibrium climate sensitivity with a similar distribution to Chapter 7, IPCC Working Group 1, AR6
• transient climate response with a similar distribution to Chapter 7, IPCC Working Group 1, AR6
• projected future warming that is of a similar distribution to the SSP scenarios of Chapter 4, IPCC Working Group 1, AR6, when run with prescribed concentrations

Changelog

• v1.1: inclusion of lightweight parameter sets.
• v1.0: original upload full parameter sets.