FAMOUS-Glimmer simulations with interactive North American and Greenland ice sheets (21ka and 140ka)

This dataset contains model inputs and outputs from ensembles of simulations and sensitivity tests performed by FAMOUS-Glimmer of the Last Glacial Maximum (LGM; 21 kilo annum before present (ka BP)) and the Penultimate Glacial Maximum (PGM; 140 ka BP), as used in the publication Patterson et al., 2024 (https://doi.org/10.5194/cp-2024-10). These data were used to help understand the difference between the North American Ice Sheet at the last two glacial maxima, explore the sensitivity of the ice sheet to uncertain model parameters and understand the role of orbit, greenhouse gases and initial conditions on the final ice sheet configurations. The output of 62 ensemble members varying climate and ice sheet model parameters for each of the LGM and PGM are included as well as the results of 8 sensitivity tests using one set of parameters but varying the initial ice sheets and climates. These simulations were created using the atmospheric general circulation model FAMOUS coupled to the Glimmer ice sheet model under LGM and PGM climate boundary conditions, including greenhouse gas concentrations and orbital parameters outlined in the PMIP4 protocols (Kageyama et al., 2017 and Menviel et al., 2019).

The model inputs include ancillary files of the prescribed sea surface temperature and sea ice fields and climate model boundary conditions, netCDF files of the ice sheet model initial condition as well as the model configuration file and updated model modifications. The outputs consist of netCDF files of monthly climate model variables from ‘Not Ruled Out Yet’ ensemble simulations, ice sheet model output from the final timestep of all ensemble simulations (including ice sheet thickness, topography, surface mass balance and velocity) and final ice sheet thickness from the sensitivity tests. Also included are excel spreadsheets of the time series of total ice volumes for all ensemble members and the list of parameter combinations used for each. The climate model data has global coverage on a 7.5x5 degree lat/lon grid. The ice sheet model data covers North America and Greenland on a Lambert Azimuthal Equal Area projection at 40x40km resolution. Each simulation was run for ~1000 climate model years, with the ice sheet model running at 10x acceleration, giving ~10,000 years of ice sheet model output.