## 2.24.5. Fire trace gas and aerosol emissions[¶](#fire-trace-gas-and-aerosol-emissions "Permalink to this headline")
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CESM2 is the first Earth system model that can model the full coupling among fire, fire emissions, land, and atmosphere. CLM5, as the land component of CESM2, calculates the surface trace gas and aerosol emissions due to fire and fire emission heights, as the inputs of atmospheric chemistry model and aerosol model.

Emissions for trace gas and aerosol species x and the j-th PFT, \\(E\_{x,j}\\) (g species s\-1), are given by

(2.24.40)[¶](#equation-23-40 "Permalink to this equation")\\\[E\_{x,j} = EF\_{x,j}\\frac{\\phi \_{j} }{\[C\]}.\\\]

Here, \\(EF\_{x,j}\\) (g species (g dm)\-1) is PFT-dependent emission factor scaled from biome-level values (Li et al., in prep, also used for FireMIP fire emissions data) by Dr. Val Martin and Dr. Li. \\(\[C\]\\) = 0.5 (g C (g dm)\-1) is a conversion factor from dry matter to carbon.

Emission height is PFT-dependent: 4.3 km for needleleaf tree PFTs, 3 km for other boreal and temperate tree PFTs, 2.5 km for tropical tree PFTs, 2 km for shrub PFTs, and 1 km for grass and crop PFTs. These values are compiled from earlier studies by Dr. Val Martin.

Table 2.24.1 PFT-specific combustion completeness and fire mortality factors.[¶](#id9 "Permalink to this table")            
| PFT
 | _CC_leaf

 | _CC_stem

 | _CC_root

 | _CC_ts

 | _M_leaf

 | _M_livestem,1

 | _M_deadstem

 | _M_root

 | _M_ts

 | _M_livestem,2

 | \\(\\xi\\)j

 |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| NET Temperate

 | 0.80

 | 0.30

 | 0.00

 | 0.50

 | 0.80

 | 0.15

 | 0.15

 | 0.15

 | 0.50

 | 0.35

 | 0.15

 |
| NET Boreal

 | 0.80

 | 0.30

 | 0.00

 | 0.50

 | 0.80

 | 0.15

 | 0.15

 | 0.15

 | 0.50

 | 0.35

 | 0.15

 |
| NDT Boreal

 | 0.80

 | 0.30

 | 0.00

 | 0.50

 | 0.80

 | 0.15

 | 0.15

 | 0.15

 | 0.50

 | 0.35

 | 0.15

 |
| BET Tropical

 | 0.80

 | 0.27

 | 0.00

 | 0.45

 | 0.80

 | 0.13

 | 0.13

 | 0.13

 | 0.45

 | 0.32

 | 0.13

 |
| BET Temperate

 | 0.80

 | 0.27

 | 0.00

 | 0.45

 | 0.80

 | 0.13

 | 0.13

 | 0.13

 | 0.45

 | 0.32

 | 0.13

 |
| BDT Tropical

 | 0.80

 | 0.27

 | 0.00

 | 0.45

 | 0.80

 | 0.10

 | 0.10

 | 0.10

 | 0.35

 | 0.25

 | 0.10

 |
| BDT Temperate

 | 0.80

 | 0.27

 | 0.00

 | 0.45

 | 0.80

 | 0.10

 | 0.10

 | 0.10

 | 0.35

 | 0.25

 | 0.10

 |
| BDT Boreal

 | 0.80

 | 0.27

 | 0.00

 | 0.45

 | 0.80

 | 0.13

 | 0.13

 | 0.13

 | 0.45

 | 0.32

 | 0.13

 |
| BES Temperate

 | 0.80

 | 0.35

 | 0.00

 | 0.55

 | 0.80

 | 0.17

 | 0.17

 | 0.17

 | 0.55

 | 0.38

 | 0.17

 |
| BDS Temperate

 | 0.80

 | 0.35

 | 0.00

 | 0.55

 | 0.80

 | 0.17

 | 0.17

 | 0.17

 | 0.55

 | 0.38

 | 0.17

 |
| BDS Boreal

 | 0.80

 | 0.35

 | 0.00

 | 0.55

 | 0.80

 | 0.17

 | 0.17

 | 0.17

 | 0.55

 | 0.38

 | 0.17

 |
| C3 Grass Arctic

 | 0.80

 | 0.80

 | 0.00

 | 0.80

 | 0.80

 | 0.20

 | 0.20

 | 0.20

 | 0.80

 | 0.60

 | 0.20

 |
| C3 Grass

 | 0.80

 | 0.80

 | 0.00

 | 0.80

 | 0.80

 | 0.20

 | 0.20

 | 0.20

 | 0.80

 | 0.60

 | 0.20

 |
| C4 Grass

 | 0.80

 | 0.80

 | 0.00

 | 0.80

 | 0.80

 | 0.20

 | 0.20

 | 0.20

 | 0.80

 | 0.60

 | 0.20

 |
| Crop

 | 0.80

 | 0.80

 | 0.00

 | 0.80

 | 0.80

 | 0.20

 | 0.20

 | 0.20

 | 0.80

 | 0.60

 | 0.20

 |

Leaves (\\(CC\_{leaf}\\) ), stems (\\(CC\_{stem}\\) ), roots (\\(CC\_{root}\\) ), and transfer and storage carbon (\\(CC\_{ts}\\) ); mortality factors for leaves (\\(M\_{leaf}\\) ), live stems (\\(M\_{livestem,1}\\) ), dead stems (\\(M\_{deadstem}\\) ), roots (\\(M\_{root}\\) ), and transfer and storage carbon (\\(M\_{ts}\\) ) related to the carbon transfers from these pools to litter pool; mortality factors for live stems (\\(M\_{livestem,2}\\) ) related to the carbon transfer from live stems to dead stems; whole-plant mortality factor (\\(\\xi \_{j}\\) ).