2022 CTSM PPE Meeting Notes

2022 CTSM PPE Meeting Notes

October 27, 2022

Agenda

• Yifan Cheng presents on Arctic hydrology parameter optimization
  • [email protected]
  • paper still in review, will update when there's a doi

Notes

• Funded via NSF Navigating the New Arctic Project
  • in collaboration with indigenous communities
  • trying to move CESM towards more actionable science
• Developed an optimization workflow for CTSM
  • utilizing ASMO
  • medlynintercept
    • high values yield cold/misty summer in Alaska
    • constrained to [1,2e4] instead of [1,2e5]
  • improved general flow simulation in 13 of 15 basins
    • better high-flow (flood) predictions
    • degraded low-flow predictions
  • snow performance is similar
    • met forcing more important than params
• Regional Arctic Systems Model
  • running the optimized parameter set with coupled CTSM-WRF (mizuRoute)
  • manual WRF namelist perturbations
  • comprehensive terrestrial hydrology and hydrometeorology assessment
  • streamflow not degraded, actually improved in >half the basins
  • importantly, utilized a previous WRF simulation for downscaling
    • minimized the shock of offline-> coupled

September 29, 2022

Agenda

• Land surface modeling summit report back
• CLM5 PPE status update (OAAT/LHC)
• Oct 27th meeting topic
• CESM coupled PPE update
  • Claire Zarakas and Abby Swann

Notes

• Land surface modeling summit
  • Sept 12-15th, Oxford, UK
  • presentations available online
  • Join the AIMES land data assimilation working group
    • https://land-da-community.github.io/
  • From Dave:
    • Dave and Eleanor Blythe will be organizing an international land modeling forum, which will be open / of interest to many involved here
    • Likely to contain working group on parameter estimation
      • many opportunities to collaborate/share across groups, including Columbia LEAP
      • e.g. https://github.com/duncanwp/ESEm
  • From Rosie:
    • Tristan Quaife will be presenting at the FATES modeling call on Nov 10th
      • land data assimilation (lavendar)
      • join fates google group: https://groups.google.com/g/fates_model
    • Kristoffer Aalstad gave a great talk recently on snow data assimilation
      • good candidate for an external presenter, here or at CLM meeting
• CLM5 PPE status update (OAAT/LHC)
  • Writing commences for OAAT, target: JAMES
  • Rerunning LHC
    • backup hiccup
    • fix GSWP3 bug
    • add krmax
  • Will save all restarts and spinup
• CESM coupled PPE update
  • Claire Zarakas ([email protected])
  • 18 parameters varied one-at-a-time
  • concentration driven, CAM6-CLM5-slab ocean
  • many interesting results!
    • large effects
    • zeta_max_stable not very important in coupled model
    • medlynslope often confusing
    • coupling affects carbon / water cycle means differently
    • coupling can erode and/or scramble IAV signals from the offline model
  • would have liked double the time to discuss
    • Claire will hopefully present again in the future