RRFS–MPAS: Add the U. Utah SLR field ("SDEN")

[jaymes-kenyon]

This PR addresses issue #1125.

Specifically, it adds the University of Utah snow-to-liquid ratio (SLR) diagnostic output to RRFS–MPAS applications, yielding a GRIB2 field abbreviated "SDEN". Recent development with this diagnostic occurred in the merged PR #1104; refer to that PR for more details.

Additionally, the current PR fixes an unrelated typo in code comments.

[JesseMeng-NOAA]

This PR addresses issue #1125.

Specifically, it adds the University of Utah snow-to-liquid ratio (SLR) diagnostic output to RRFS–MPAS applications, yielding a GRIB2 field abbreviated "SDEN". Recent development with this diagnostic occurred in the merged PR #1104; refer to that PR for more details.

For the "SDEN" field, note that the current PR specifies <scale>3.0</scale>, rather than the default setting of 6.0.

Additionally, the current PR fixes an unrelated typo in code comments.

Please modify <scale>3.0</scale> to 6.0. Thanks.

[WenMeng-NOAA]

@jaymes-kenyon @JesseMeng-NOAA Could you take a look at my UPP standalone test for MPAS at /home/Wen.Meng/stmp2/mpas_2024112100-after on Hera?
It appears to me the SLR field "SDEN" was successfully generated as:

 wgrib2 WRFTWO12.tm00 -match SDEN -s -stats
40:36132094:d=2024112012:SDEN:surface:12 hour fcst::ndata=1905141:undef=1459740:mean=88.4948:min=45.653:max=679.477:cos_wt_mean=89.7173

Please let me know if you see issues.

[WenMeng-NOAA]

The UPP RTs have been completed on WCOSS2 without baseline changes.

[jaymes-kenyon]

@JesseMeng-NOAA @WenMeng-NOAA — I added a third commit to address Jesse's request, bit the commit seems to be hanging in GitHub. The upper-right corner of this page still says "processing updates". Hopefully this PR will show the new commit soon.

[WenMeng-NOAA]

@JesseMeng-NOAA @WenMeng-NOAA — I added a third commit to address Jesse's request, bit the commit seems to be hanging in GitHub. The upper-right corner of this page still says "processing updates". Hopefully this PR will show the new commit soon.

@jaymes-kenyon It looks like the 'processing update' status is stuck. Could you try opening a new PR?

[jaymes-kenyon]

@WenMeng-NOAA — Due to GitHub issues, this PR (now closed) was replaced by PR #1132.