Smoke/Dust Enhancements to the UFS WM

[JohanaRomeroAlvarez]

GSL would like CM assistance merging smoke/dust model enhancements into UFS WM repos and making these enhancements available in the SRW.

All updates to the UFS model, and subsequent submodules, are available here: https://github.com/LiamWedell-NOAA/ufs-weather-model/tree/fireteam, https://github.com/LiamWedell-NOAA/fv3atm/tree/fireteam, https://github.com/LiamWedell-NOAA/ccpp-physics/tree/fireteam.

Plume Rise Changes

• Modifying water vapor content based on emissions

• Add two default layers to emission distribution

• Scaling factor for fire heat fluxes (to be added into fireteam branch)

Other Smoke and Dust Changes

• Capability to handle 6-hourly emissions and scaling factor between 24- and 6-hourly emissions

• Safeguard for kpbl on first timestep

• Read in ecosystem map (to be merged into fireteam branch)

Workflow Requirements
Modification of the Fire Emissions Preprocessor to Support new PM2.5 Emissions
GSL intends to replace the vegetation maps with a version that represents PM2.5 emissions in g MJ⁻¹. This is calculated as:

• Emission factor for PM2.5 (g kg⁻¹) ×β (kg MJ⁻¹)

We have observed that the model underestimates emissions in Canada, particularly for fires that burn for extended periods in a smoldering phase within organic soils. To improve this representation, we propose updating:

• All vegetation maps for the predefined grids.

• The equation used to estimate biomass emissions rates

• Workflow Update for Forecast Emissions

GSL also requests an option in the workflow to ingest emissions used in forecast mode (ebb_dcycle option 2), allowing for emissions to be represented as:

• A 24-hour average of emissions, or

• An average calculated every 6 hours, always looking back 24 hours before the forecast starts.

This is achieved by introducing a new UFS model parameter, HWP_Alpha, which will inform the workflow on which method to use in the forecast. The goal is to better represent the diurnal cycle in the forecast, as the averaged emissions provide a more realistic picture of how emissions evolve throughout the day.
These changes will be accompanied by updates to the UFS model and namelist settings, as specified above.

[jdkublnick]

Hello,

Thank you for taking the time to share your enhancement. Your request will be forwarded to CM and Program Management for review and consideration in upcoming Planning Intervals (PIs).

Thank you,

Joshua Kublnick