CESM2 IMBIE simulation output: Antarctic Ice Sheet freshwater discharge drives substantial Southern Ocean changes over the 21st century

Output from one of two CESM2 simulations aimed at exploring the impacts of Antarctic freshwater discharge on the Southern Ocean over the 21st century. Contained in these files are the primary model output variables needed to investigate sea ice, potential temperature, potential density, and the mixed layer depth (used to derive deep convective area). "AIS" or "IMBIE" refers to a simulation with increasing liquid and solid freshwater runoff in the Amundsen and Bellingshausen Seas region. "hist" refers to the period from Jan 1970 - Dec 2014 which was run under historical CMIP6 atmospheric forcing and "ssp585" refers to the period from Jan 2015 - Dec 2099 which was run under SSP5-8.5 CMIP6 atmospheric forcing.

Each variable is output as a global field with \(\sim0.9\times1.25^\circ\) horizontal resolution and monthly temporal resolution. Potential density and temperature both contain 60 depth levels.

Density

1. "FW_AIS_hist.pop.h.PD.199201-201412.nc" contains the potential density field from Jan 1992 - Dec 2014 for the "AIS" ("IMBIE") simulation

2. "FW_AIS_ssp585.pop.h.PD.201501-209912.nc" contains the potential density field from Jan 2015 - Dec 2099 for the "AIS" ("IMBIE") simulation

Mixed Layer Depth (for deep convective area)

3. "FW_AIS_hist.pop.h.XMXL.199201-201412.nc" contains the maximum mixed layer depth field from Jan 1992 - Dec 2014 for the "AIS" ("IMBIE") simulation

4. "FW_AIS_ssp585.pop.h.XMXL.201501-209912.nc" contains the maximum mixed layer depth field from Jan 2015 - Dec 2099 for the "AIS" ("IMBIE") simulation

Temperature

5. "FW_AIS_hist.pop.h.TEMP.199201-201412.nc" contains the potential temperature field from Jan 1992 - Dec 2014 for the "AIS" ("IMBIE") simulation

6. "FW_AIS_ssp585.pop.h.TEMP.201501-209912.nc" contains the potential temperature field from Jan 2015 - Dec 2099 for the "AIS" ("IMBIE") simulation

Sea Ice

7. "FW_AIS_hist.pop.h.IFRAC.199201-201412.nc" contains the sea ice fraction per grid cell field from Jan 1992 - Dec 2014 for the "AIS" ("IMBIE") simulation

8. "FW_AIS_ssp585.pop.h.IFRAC.201501-209912.nc" contains the sea ice fraction per grid cell field from Jan 2015 - Dec 2099 for the "AIS" ("IMBIE") simulation

Other

9. "gx1_v7_area1.nc" contains the area field for the CESM2 (POP) ocean grid

Please contact Tessa Gorte if you have any questions about these data and/or the simulations used to generate them.