Passive Crown Fire development #572
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Add EQ to evaluate potential for crown fire Add EQ for passive crown fire igntion Set fraction of crown burnt based on this conditional Add crown fire threshold, crown fire flag, and crown fire PFT param
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I am still testing these changes, but welcome comments on the logic and flow of the changes. |
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@jkshuman your changes seem good to me. |
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This implementation addresses issue #567 and replaces the branch that @slevisconsulting started on that issue. The active development branch for this is https://github.com/jkshuman/fates/tree/passive_crown_fire |
Following @jkshuman's introduction of the Bessie and Johnson (1995) formulation for determining the presence of passive crown fire (NGEET/fates#572), I now add the same paper's formulation for determining the presence of active crown fire. The corresponding issue is NGEET/fates#573
Co-Authored-By: Samuel Levis <[email protected]>
main/EDPftvarcon.F90
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| @@ -49,8 +49,7 @@ module EDPftvarcon | |||
| ! that is occupied by crown. For fire model. | |||
| real(r8), allocatable :: bark_scaler(:) ! scaler from dbh to bark thickness. For fire model. | |||
| real(r8), allocatable :: crown_kill(:) ! crown resistance to fire. (1 = none) For fire model. | |||
| real(r8), allocatable :: active_crown_fire(:) ! Is plant susceptible to active crown fire?(1=yes,0=no) | |||
| real(r8), allocatable :: foliar_moisture(:) ! foliar moisture content from dry fuel [%] | |||
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Strange, it wants to remove foliar_moisture, but foliar_moisture is not in master.. I wonder if git is confused...?
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Implementation EQ 14 of Bessie and Johnson has been updated per Scott and Reinhardt 2001 to consider stand level canopy fuel density versus tree level fuels for crown fire initiation on a patch #572 and integrated into #584 . edited in PR above. Canopy base height for the stand is the height at which a minimum fuel bulk density of (0.011 kg/m3) is found. This accounts for variation in fuels within multi-story stands. |
Add equation to evaluate potential for crown fire at level of cohort and PFT
Add equation for passive crown fire ignition
Set fraction of crown burnt based on this conditional
Add crown fire threshold, cohort crown fire flag, and crown fire PFT param
Description:
This PR addresses passive crown fire development as a function of the stand. Within SPITFIRE crown fire ignition potential is evaluated against fire intensity using equations and logic from Bessie and Johnson (1995) that are drawn from Van Wagner (1977) at the stand level per Scott and Reinhardt (2001). Here the heat of crown foliage ignition is set to a constant value of 3060 kJ/kg based on 100% moisture (dry mass), but can be calculated via FATES-Hydro with additional development. (Comments indicate where this calculation would occur and be used this.) With successful passive crown fire ignition, active crown fire initiation is evaluated with PR #584
Crown damage is evaluated via scorch height per usual.
Collaborators:
main author: @jkshuman
@slevisconsulting @lmkueppers @ckoven @pollybuotte @rgknox @rosiealice @xuchongang
Expectation of Answer Changes:
yes. this will change answers in fire runs that use crown fire PFTs. crown damage fraction has higher potential of being 100%.
Checklist:
Test Results:
CTSM (or) E3SM (specify which) test hash-tag:
CTSM (or) E3SM (specify which) baseline hash-tag:
FATES baseline hash-tag:
Test Output: