Update emissivity to 0.985 and set nblyr default to 1

[apcraig]

PR checklist

• Short (1 sentence) summary of your PR:
  Update emissivity to 0.985 and set nblyr default to 1
• Developer(s):
  apcraig
• Suggest PR reviewers from list in the column to the right.
• Please copy the PR test results link or provide a summary of testing completed below.
  Full test suites run on cheyenne on 3 compilers, most results are NOT bit-for-bit.
  https://github.com/CICE-Consortium/Test-Results/wiki/cice_by_hash_forks#c4b9051c28db9ab818669133a72be687d8846c0e
• How much do the PR code changes differ from the unmodified code?
  • bit for bit
  • different at roundoff level
  • more substantial
• Does this PR create or have dependencies on Icepack or any other models?
  • Yes
  • No
• Does this PR add any new test cases?
  • Yes
  • No
• Is the documentation being updated? ("Documentation" includes information on the wiki or in the .rst files from doc/source/, which are used to create the online technical docs at https://readthedocs.org/projects/cice-consortium-cice/. A test build of the technical docs will be performed as part of the PR testing.)
  • Yes
  • No, does the documentation need to be updated at a later time?
    • Yes
    • No
• Please provide any additional information or relevant details below:

See #249

Change emissivity default to 0.985 (from 0.95)
Change nblyr default to 1 (from 7)
Add nblyr=7 to set_nml.zsal
Update Icepack to include emissivity default changes
Update documentation as needed

[apcraig]

Do we need/want to do a QC test? Would we expect it to pass?

[eclare108213]

A QC test would certainly be interesting. I wouldn't expect it to pass in stand-alone mode based on prior sensitivity tests, but it might pass. For completeness, I think it's a good idea to run a QC test.

[apcraig]

The QC test passed on cheyenne. I'm not sure whether this is a good or bad outcome.

INFO:main:Running QC test on the following directories:
INFO:main: /glade/scratch/tcraig/CICE_RUNS/cheyenne_intel_smoke_gx1_36x1_medium_qc.qc_base
INFO:main: /glade/scratch/tcraig/CICE_RUNS/cheyenne_intel_smoke_gx1_36x1_medium_qc.qc_test
INFO:main:Number of files: 1460
INFO:main:2 Stage Test Passed
INFO:main:Quadratic Skill Test Passed for Northern Hemisphere
INFO:main:Quadratic Skill Test Passed for Southern Hemisphere
INFO:main:Quality Control Test PASSED

[eclare108213]

Was this run with JRA forcing? Then it's good. I'd expect it to fail with the old forcing, which is a lot of the reason for moving to JRA. Sensitivities using the old forcing had the wrong sign!

[apcraig]

Yes, this is with JRA55 forcing.

[eclare108213]

I think it's fine to merge this, assuming that the issues that @dabail10 is turning up are related to configuration settings specific to his tests rather than these code changes.

[dabail10]

This was a problem related to my setup and not the emissivity value change.

[dabail10]

I just verified that even with emissivity of 0.95, I cannot do a run crossing 1996 to 1997 (starting in 1995) with my JRA forcing. I believe there is a leap year related issue here. I will open a separate issue.