New Mesh: SOwISC12to30E3r4

[xylar]

Long name: SOwISC12to30kmL80E3SMv3r4

This version of the Southern Ocean Regionally Refined Mesh (SORRM) has resolution that is:

• 12 km resolution around Antarctica
• 30 km elsewhere

It is intended to be similar to the Icos30 mesh except in the Southern Ocean and around Antarctica.

This mesh differs from r3 in #807 in that:

• MALI topography as well as masks for land ice, floating ice and ocean get combined with BedMachine Antarctica/GEBCO.

Checklist

• User's Guide has been updated
• Developer's Guide has been updated
• API documentation in the Developer's Guide (api.rst) has any new or modified class, method and/or functions listed
• Documentation has been built locally and changes look as expected
• The E3SM-Project submodule has been updated with relevant E3SM changes
• Document (in a comment titled Testing in this PR) any testing that was used to verify the changes

[xylar]

This is based off of #807 (which is based off of #813) so it will be a bit before this is ready to go in. It also needs documentation.

[xylar]

Comparison with SOwISC12to30E3r3

Here are the landIceMask fields for the SORRM mesh with MALI topography:

And the same but with BedMachine from #807:

[xylar]

Updated Comparison with SOwISC12to30E3r3

Here are the landIceMask fields for the SORRM mesh with MALI (AIS_2to10km) topography:

And the same but with BedMachine from #807:

[xylar]

I was able to run the workflow through the performance test. In a discussion with @cbegeman, @matthewhoffman and @trhille, we decided we'd like to work with a 4km initial condition that's more similar to the 2km one I used in the plots above, and that that initial condition would also be swapped into E3SM-Project/E3SM#6440, the PR bringing in the new MALI AIS meshes and initial conditions.

[xylar]

Another Updated Comparison with SOwISC12to30E3r3

Here are the landIceMask fields for the SORRM r4 mesh with MALI (AIS_4to20km) topography:

And the same but SORRM r3 with BedMachine topography from #807:

[xylar]

The same as above but zooming in on the Amundsen Sea.

SORRM r4:

SORRM r3:

[cbegeman]

@xylar have you been looking at all at landIceFloatingFraction?

[xylar]

Testing

Tested on an 11-year G-case as described in E3SM-Ocean-Discussion/E3SM#120

[xylar]

@matthewhoffman and @cbegeman, if you could review this along with E3SM-Project/E3SM#7195, that would be wonderful!

[maltrud]

the differences in Arctic SSS appear to be due to changing from PHC2.0 to WOA23 for the SSS climatology. here's a plot of annual average SSS (WOA - PHC):

[cbegeman]

Approving on the basis of testing and visual inspection of these code changes. Thanks @xylar!

[xylar]

@maltrud, I agree, that's what I attribute those changes to, as well. The freshening seems like a move in the wrong direction, right? So something we may want to revisit (separate from this PR).

[xylar]

@matthewhoffman, anything else?

[matthewhoffman]

@xylar , no, I don't have any other suggestions.

[xylar]

Great, thanks so much @matthewhoffman and @cbegeman!!!