[Nomad FR]: Zero Deterministic Mode spread under specified conditions

[Den-Boychuk]

Contact Details

GitHub @Den-Boychuk

What is needed?

Summary:

• For deterministic FireSTARR simulations, consider implementing a feature for users to zero out fire spread under specified burning conditions and overnight.
• Analysts are used to having this feature in Prometheus and FireCast.

Background:

• FBP is known to overestimate ROS, particularly in low to moderate conditions.

• Analysts typically zero out fire spread overnight and when weather or fire weather are below specified thresholds.

• Prometheus (2010) and FireCast (2023) had optional settings like these:

  • Prometheus and FireCast:
    • Burning period start and end times for all days
  • Prometheus:
    • Wind speed and RH thresholds
  • FireCast:
    • By-agency conditions on FWI System (and maybe weather) values
    • Multiple conditions were said to be connected with AND operators, but I don't know how the conditions were framed. For example, both of the following use AND conditions, but they have different results:
      • if ISI < 8 AND FFMC < 80 then ROS = 0
      • if ISI > 8 AND FFMC > 80 then ROS uses FBP

• FireSTARR's Probabilistic Mode zeros out fire spread "randomly" by hour and cell using multiple thresholds that depend on fire weather or fire behaviour conditions. Fires occasionally spread overnight under sufficiently extreme conditions.

• FireSTARR's Deterministic Mode does not zero out fire spread or otherwise alter the input weather data. Analysts would have to “manually” alter the input weather data to zero out fire spread, e.g., by setting hourly FFMC = 0 overnight and when, say, FFMC < 80.

Feature:

• A Nomad UI feature that altered input weather data to zeroing out fire spread under specified time and fire weather conditions would be a convenience.
• Users would need to be consulted about what conditions to include and how they are framed
• This feature should not be available for Probabilistic Mode.

How will this improve the project or tool?

This would speed the work of users.

[nealmcloughlin]

This would be a Nomad feature to zero out the fire weather indices for the hours you don't want to see fire growth in your simulation.

[emdiaz0031]

@spydmobile

• The burning-conditions service should expose one common UI, but surface different internal operations depending on the selected model.
• We are not building this feature specifically for FireStar; the UI should be model-agnostic.
• The user’s choices (e.g., “no spread during these hours/conditions”) are expressed once in the UI, and the mechanics for each model (FireStar, Prometheus, WISE, etc.) are handled separately under the hood.
• This allows us to add new models later without rewiring the UI, only by implementing the appropriate mechanics in the burning-condition service for that model.

@nealmcloughlin One shared UI for “no-spread” conditions; each model applies that rule in its own way.

[BadgerOnABike]

Within this feature I would suggest we have a display of the weather for the user to be able to see which hours would result in burning being limited.