Skip to content

CCPP Framework Meeting Minutes 2021 12 02

Jump to bottom
ligiabernardet edited this page Dec 3, 2021 · 4 revisions

Agenda

Transition to capgen.py

  • https://github.com/ufs-community/ufs-weather-model/pull/907 and associated PRs updated the metadata parser with the new code from feature/capgen
    • Stricter unit checking required updating several units in fv3atm and ccpp-physics metadata, some of it being controversial
    • Follow-up: spell 'frac' out as 'fraction' for consistency, update CCPPStandardNames repo with the changes in the above PRs
    • log(Pa) was replaced with 1, additional information addedd to long name
      • This means we loose the ability to do automated unit conversion
      • Should units in CCPP are an extended definition of actual units that allows things to be converted, i.e. put log(Pa) back in
      • In ozne_def and h2o_def, it should be ln(Pa) and not log(Pa)
    • Pa**kappa: - unit to the power of some number is a real thing
      • Could we pass pressure and kappa separately? Dom to check
    • Best option would be to pass around the actual quantities and not functions of it
      • But if the function is used in many places, then this slows things down
      • Need to understand how widespread this situation is (is it just log(Pa) or are there more such cases, e.g. in chemistry)
      • We need to be able to support modified variables such as xyz_multiplied_by_timestep_abc, but this is not interoperable
      • Are these non-portable qualifiers in the dictionary?
      • Add information to section "Best practices" in the CCPP technical documentation to try to avoid using these non-portable variables and units, but don't make it a rule

Dictionary of standard names

  • Is specific humidity the mass mixing ratio of vapor with respect to moist air or with respect to total mass (rule 5)?
    • Correct would be w.r.t. total mass, but UFS / ccpp-physics are using it incorrectly as w.r.t. moist air
    • AMS glossary says specific humidity is w.r.t. total mass, but there are other definitions in the literature
    • Outlow use of specific humidity,m and always use mixing_ratio_of_vapor_wrt_xyz?
    • Dom to discuss this with Moorthi and Fanglin

CCPP requirements document

  • Update from last CCPP Physics Code Management committee meeting: Matt's suggestion acceptable to all
    • Keep requirements doc as historical evidence
      • Add watermark on each page? Laurie knows how to do this
    • Then use CCPP tech doc for current capabilities/requirements + github issues for future development

Other business

  • Changes to Google Meet settings - need to enable quick access (Steve)
  • Handling constituent information originating from a physics scheme
    • Waiting for Steve to return from AL
  • Specifying a data source for an input variable (see #413)
    • Waiting for Steve to return from AL
  • Who will prepare and run the framework meetings in Dom's absence?
    • Dom will participate until Feb 27, 2022, but stop preparing and leading the meeting by the end of 2021
    • Best done by the actual developers
    • GSL will hire someone to replace Dom and do the framework development, but this will take months
    • NCAR will also hire someone, but this will take months as well
  • CCPP visioning workshop
    • Mike and Ligia are spearheading a proposal due mid-Dec
    • Needed to gather community input needed on framework development
    • Framework development should be guided by science needs
    • Possible developments that come to mind are: half/single/double precision, advanced/mixed architectures (GPU etc.), 3D physics, etc.
    • Also desire to clean the plethora of interstitial schemes and streamline suites
    • TBD: How to gather science needs from communities associated with MPAS/WRF/CAM-CESM. Could connect with the Winter CESM Atmos Working Group in Feb
    • TBD: How to deal with requests for things that the CCPP cannot do due to its structural design (possible limitations wrt aerosol/chem interfaces)

CCPP Framework wiki

Clone this wiki locally