A_WCYCL1950S_CMIP6_HR
Overview:
This is a coupled compset with perpetual 1950 forcings based on CMIP6 input4mips data. It is based on the HighResMIP protocol as described in: https://www.geosci-model-dev.net/9/4185/2016/gmd-9-4185-2016.pdf, except prognostic (MAM4) aerosols are used and the ocean is only spunup for 3 years in a g-case from CORE, starting with PHC instead of the EN4 product. Most of the forcings were derived from A_WCYCL1850S_CMIP6 and A_WCYCL20TRS_CMIP6 compsets. (TODO: turn the prev compset names into links to their pages). "_HR" is appended to indicate that high-res tuning parameters rather than low-res tuning parameters are included in the compset specification. Some input data is also specified at higher resolution than done for low-res compsets.
Ocean Initial Condition:
- Ocean/ice initial condition comes from running an active ocean sea-ice simulation (G-case) for 3 yrs and grabbing its state from the beginning of year 4.
- This ocean sea-ice simulation is forced by the COREv2 dataset (Large and Yeager, 2009).
- The G-case simulation is initialized in two phases.
- First, the ocean state is initialized from a blended observations project (World Ocean Circulation Experiment and Polar Hydrographic Climatology datasets). The ocean is run alone for a 30 days to allow gravity wave propagation, increasing the maximum allowed timestep for E3SM cases.
- Second, this slightly spun up state is then used in the G-case. The initial sea-ice distribution are hemispheric caps of constant thickness.
- We also experimented with using the UKMO's EN4 estimate which is used in the HighResMIP protocol and is a better proxy for 1950 conditions as the ocean IC (in place of the WOCE+PHC product), but the simulation was warmer/worse than our default approach.
Land Initial Condition:
Atmosphere Initial Condition:
Aerosol Emissions:
includes prognostic aerosols driven by anthropogenic and open fire emissions directly taken from the CMIP6 protocol (as of May 2017) except for SOA gas precursor emissions that are modified to emit from elevated sources as well.
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