WACCM DECK runs should be configured similarly to CAM DECK runs, but without virtual elevation classes over Antarctica. (2018-10-22) In discussions between Bill Sacks and Bill Lipscomb: We have decided NOT to turn on virtual Antarctica columns for any of the WACCM simulations (DECK or ScenarioMIP): these weren't turned on in the WACCM PI-Control or historical runs (either by accident or intentionally: I'm not sure which, and can't find emails describing this decision). Since this setting needs to be compatible with the REFCASE, it's simpler if we keep it consistent for all WACCM runs, and there seems to be only limited value in turning on virtual Antarctica columns in the remaining WACCM runs (1% CO2, 4xCO2 and ScenarioMIP) when they weren't on in the WACCM PI-Control or Historical runs. And Mike Mills says that there won't be any more sharing of initial conditions between CAM and WACCM CMIP6 runs, so it's fine if the two sets remain different in this respect.