Fuel fraction burnt, rate of spread and fuel consumed calculated - regardless of ignition events or fire danger

[adrifoster]

From the current SPITFIRE code order :

   if (hlm_spitfire_mode > hlm_sf_nofire_def) then
      call UpdateFireWeather(currentSite, bc_in)
      call UpdateFuelCharacteristics(currentSite)
      call rate_of_spread(currentSite)
      call ground_fuel_consumption(currentSite)
      call area_burnt_intensity(currentSite, bc_in)
      call crown_scorching(currentSite)
      call crown_damage(currentSite)
      call cambial_damage_kill(currentSite)
      call post_fire_mortality(currentSite)
    end if

We always calculate rate of spread, fuel consumption, and fire intensity, regardless of the fire danger index or ignition events. This means that we could have a fraction burnt of 0.0, and no fire (fire=0), but the patch would still have some value for fire rate of spread and fire intensity, and fuel%frac_burnt.

Currently the only things that are set to zero in the case of 0.0 FDI or no ignitions are:

            currentPatch%fire       = 0 ! No fire... :-/
            currentPatch%FD         = 0.0_r8
            currentPatch%frac_burnt = 0.0_r8

This doesn't impact cohort mortality, though from my read of the code we still remove fuel by the fraction burnt. I'm pretty sure this is NOT what we want to do??

can someone confirm that this is what is actually happening? I think this might seriously impact us...

Okay confirmed with @glemieux that this is not an issue because of the way we calculate the litter transfers... but see #1301