Update mksurfdata_map to include glaciers outside of pft landmask

[lawrencepj1]

… as well as lakes and wetlands outside of the landmask

with new code:

<        ! Assume wetland, glacier and/or lake when dataset landmask implies ocean

<           if (pctgla(n) < 1.e-6_r8) then
<               pctwet(n)    = 100._r8 - pctlak(n)
<               pctgla(n)    = 0._r8
<           else
<               pctwet(n)    = 100._r8 - pctgla(n) - pctlak(n)
<           end if

from

>        ! Assume wetland and/or lake when dataset landmask implies ocean

>           pctwet(n)        = 100._r8 - pctlak(n)
>           pctgla(n)        = 0._r8

Description of changes

Specific notes

Contributors other than yourself, if any:

CTSM Issues Fixed (include github issue #):
Addresses #545 (fixing it will require new surface datasets generated with this code)

Are answers expected to change (and if so in what way)?

Any User Interface Changes (namelist or namelist defaults changes)?

Testing performed, if any:
(List what testing you did to show your changes worked as expected)
(This can be manual testing or running of the different test suites)
(Documentation on system testing is here: https://github.com/ESCOMP/ctsm/wiki/System-Testing-Guide)
(aux_clm on cheyenne for gnu/pgi and hobart for gnu/pgi/nag is the standard for tags on master)

NOTE: Be sure to check your Coding style against the standard:
https://github.com/ESCOMP/ctsm/wiki/CTSM-coding-guidelines

[billsacks]

Thanks, @lawrencepj1 !

[ekluzek]

@billsacks and I discussed this and realized we want this on master, but NOT on the release branch. We'll probably create datasets on master, that we then move to the release branch (for future scenarios), but we want to make sure you can create the old style datasets on the release branch.

I thought this PR might've been to go to the release branch, but it is correctly being sent to master.

[billsacks]

Update: Based on today's co-chairs discussion, we actually want this on both master and the release branch. We want both the updated mksurfdata_map and all new surface datasets to come out-of-the-box starting in CESM2.1.1. To be clear: Starting with CESM2.1.1, all CTSM surface datasets should have this bug fix, and so should have glaciers rather than wetlands over the Antarctic ice shelves. This will mean that CESM2.1.1 changes answers relative to CESM2.1.0, and that is deemed acceptable. (We should just carefully check the new surface datasets against the old to ensure that the only thing that changes is this one aspect.)

In discussion over lunch, @ekluzek and I agreed that he would make this change in time for the CESM2.1.1 release. The earlier the better, probably, in terms of supporting upcoming cmip6 runs out-of-the-box, but there isn't a critical need for it before that release.

[ekluzek]

I'm going to put this on the release branch first and then move to master.

[ekluzek]

I've put this on the release branch.