Dataset for "Future projections for the Antarctic ice sheet until the year 2300 with a climate-index method"

2023-07-03 Dataset for “Future projections for the Antarctic ice sheet until the year 2300 with a climate-index method” (Journal of Glaciology, doi: 10.1017/jog.2023.41) – README – Ralf Greve1,2, Christopher Chambers1, Takashi Obase3, Fuyuki Saito4, Wing-Le Chan3,4, Ayako Abe-Ouchi3 1 Institute of Low Temperature Science, Hokkaido University, Sapporo, Japan 2 Arctic Research Center, Hokkaido University, Sapporo, Japan 3 Atmosphere and Ocean Research Institute, University of Tokyo, Kashiwa, Japan 4 Japan Agency for Marine-Earth Science and Technology, Yokohama, Japan 19 model experiments (for details see Table 1 and the paper) • HIST: historical simulation 1990–2015. • CTRL (Exp. #0): constant-climate projection control experiment 2015–2301. • Exps. #5–10, 12–13, A5–A8, B6–B10: future-climate experiments 2015–2301; see Table 1. • SICOPOLIS run-specs header files in archive run_specs_headers.zip. Variables The variable names follow closely the ISMIP6 convention (e.g., Table A1 of https://tinyurl.com/ismip6-wiki-ais). However, years are used instead of seconds as the time unit (1 a = 3.1556926 × 107 s). Time itself is counted in years CE. 2D variables are provided on the native 8-km grid of SICOPOLIS (EPSG:3031). 2D state variables (in archives hist.zip, ctrl_proj_ext.zip, exp05_ext.zip, …, expB10_ext.zip) lithk – Ice thickness (m) orog – Surface elevation (m) base – Ice base elevation (m) topg – Bedrock elevation (m) 2 xvelsurf – Surface velocity in x (m a−1) yvelsurf – Surface velocity in y (m a−1) zvelsurf – Surface velocity in z (m a−1) horvelsurf – Horizontal surface velocity (m a−1) xvelbase – Basal velocity in x (m a−1) yvelbase – Basal velocity in y (m a−1) zvelbase – Basal velocity in z (m a−1) horvelbase – Horizontal basal velocity (m a−1) xvelmean – Mean velocity in x (m a−1) yvelmean – Mean velocity in y (m a−1) horvelmean – Horizontal mean velocity (m a−1) litemptop – Surface temperature (K) litempbot – Basal temperature (K) strbasemag – Basal drag (Pa) sftgif – Land ice area fraction (–) sftgrf – Grounded ice sheet area fraction (–) sftflf – Floating ice shelf area fraction (–) These variables are provided as snapshots for the following years: hist: 1991 (1) 2015, all other experiments: 2035 (20) 2295, 2301. Time variable: ‘time’. 2D flux variables (in archives hist.zip, ctrl_proj_ext.zip, exp05_ext.zip, …, expB10_ext.zip) acabf – Surface mass balance flux (kg m−2 a−1) libmassbf – Basal mass balance flux (kg m−2 a−1) licalvf – Calving flux (kg m−2 a−1) dlithkdt – Ice thickness imbalance (m a−1) hfgeoubed – Geothermal heat flux (W m−2) These variables are provided as averages over the intervals bounded by the following years: hist: 1990 (1) 2015, all other experiments: 2015 (20) 2295 + a final snapshot for 2301. Time variables: ‘time’, ‘time_bnds’. Scalar state variables (in common archive all_scalar.zip) lim – Total ice mass (kg) limnsw – Mass above floatation (kg) iareagr – Grounded ice area (m2) iareafl – Floating ice area (m2) 3 These variables are provided as yearly snapshots for the following full years: hist: 1991–2015, all other experiments: 2016–2301. Time variable: ‘time’. Scalar flux variables (in common archive all_scalar.zip) dlimdt – Total ice mass change (kg a−1) tendacabf – Total surface mass balance flux (kg a−1) tendlibmassbf – Total basal mass balance flux (kg a−1) tendlibmassbffl – Total basal mass balance flux beneath floating ice (kg a−1) tendlicalvf – Total calving flux (kg a−1) These variables are provided as yearly averages over the intervals bounded by the following years: hist: 1990–2015, all other experiments: 2015–2301. Time variables: ‘time’, ‘time_bnds’. Note For further details on the variables, see the metadata in the netCDF files (e.g., by Linux command ‘ncdump –h’ or MATLAB command ‘ncdisp’). 4 Exp. # GCM Scenario Ocean forcing Ice-shelf fracture 0 — CTRL — — Control exp. 5 NorESM1-M RCP8.5 Medium No Core experiments (Tier 1) 6 MIROCESM-CHEM RCP8.5 Medium No 7 NorESM1-M RCP2.6 Medium No 8 CCSM4 RCP8.5 Medium No 9 NorESM1-M RCP8.5 High No 10 NorESM1-M RCP8.5 Low No 12 CCSM4 RCP8.5 Medium Yes 13 NorESM1-M RCP8.5 PIGLMedium No A5 HadGEM2-ES RCP8.5 Medium No Extended ensemble (Tier 2) A6 CSIRO-Mk3.6.0 RCP8.5 Medium No A7 IPSL-CM5A-MR RCP8.5 Medium No A8 IPSL-CM5A-MR RCP2.6 Medium No B6 CNRM-CM6-1 SSP5-8.5 Medium No CMIP6 extension (Tier 2) B7 CNRM-CM6-1 SSP1-2.6 Medium No B8 UKESM1-0-LL SSP5-8.5 Medium No B9 CESM2 SSP5-8.5 Medium No B10 CNRM-ESM2-1 SSP5-8.5 Medium No Table 1. Extended ISMIP6-Antarctica Tier-1 and Tier-2 future climate experiments for the period 2015–2301 (= end of 2300). See the paper for further details.