6.29. triffid_params.nml

This file contains a single namelist called JULES_TRIFFID that sets parameters relevant to the TRIFFID submodel.

6.29.1. JULES_TRIFFID namelist members

This namelist is used to read PFT parameters that are only needed by the dynamic vegetation model (TRIFFID). Values are not used if TRIFFID is not selected.

Note

Where a quantity is said to have units of “/360days”, this means that it is an amount per 360 days.

Note

If the crop model is on (i.e. ncpft > 0), only nnpft = npft - ncpft values will be used for each variable.

JULES_TRIFFID::crop_io
Type

integer(npft)

Permitted

0,1,2,3

Default

None

Flag indicating whether the PFT is natural, crop, or pasture. Only crop / pasture PFTs are allowed to grow in the agricultural area. See l_trif_crop for more details.

If l_trif_crop is FALSE permitted values of crop_io are 0 and 1.

  1. Natural vegetation (not a crop).

  2. A crop.

If l_trif_crop is TRUE permitted values of crop_io are 0, 1 and 2.

  1. Natural vegetation (neither crop nor pasture).

  2. Crop.

  3. Pasture.

If l_trif_biocrop is TRUE permitted values are 0, 1, 2 and 3. Flag indicating whether the PFT is natural, crop, pasture, or bioenergy. See l_trif_biocrop for more details.

  1. Natural vegetation.

  2. Crop.

  3. Pasture.

  4. Bioenergy crops or trees.

JULES_TRIFFID::g_area_io
Type

real(npft)

Default

None

Disturbance rate (/360days).

JULES_TRIFFID::g_grow_io
Type

real(npft)

Default

None

Rate of leaf growth (/360days).

JULES_TRIFFID::g_root_io
Type

real(npft)

Default

None

Turnover rate for root biomass (/360days).

JULES_TRIFFID::g_wood_io
Type

real(npft)

Default

None

Turnover rate for woody biomass (/360days).

JULES_TRIFFID::lai_max_io
Type

real(npft)

Default

None

Maximum LAI.

JULES_TRIFFID::lai_min_io
Type

real(npft)

Default

None

Minimum LAI.

JULES_TRIFFID::alloc_fast_io
Type

real(npft)

Default

None

Fraction of the carbon flux from vegetation to wood products to add to the rapidly decaying wood products pool (wood_prod_fast).

JULES_TRIFFID::alloc_med_io
Type

real(npft)

Default

None

Fraction of the carbon flux from vegetation to wood products to add to the wood products pool with a moderate decay rate (wood_prod_med).

JULES_TRIFFID::alloc_slow_io
Type

real(npft)

Default

None

Fraction of the carbon flux from vegetation to wood products to add to the slowly decaying wood products pool (wood_prod_slow).

JULES_TRIFFID::retran_l_io
Type

real(npft)

Default

0.5

Fraction of retranslocated leaf N.

JULES_TRIFFID::retran_r_io
Type

real(npft)

Default

0.2

Fraction of retranslocated root N.

JULES_TRIFFID::ag_expand_io
Type

integer(npft)

Permitted

0,1

Default

0

Only used if l_ag_expand = TRUE.

  1. No automatic expansion of PFT area when the agricultural area increases.

  2. Automatically plant out new crop areas with the selected PFT.

Only used when l_trif_biocrop = TRUE

JULES_TRIFFID::harvest_type_io
Type

integer(npft)

Permitted

0,1,2

Default

0

  1. No harvest (default).

  2. Continuous harvest from litter, as per l_trif_crop.

  3. Periodic harvesting.

Note

For “natural” PFTs (crop_io = 0), this must be set to 0. For agricultural PFTs, this can be set to 0, 1 or 2.

Only used when harvest_type_io = 2

A placeholder value must be used for all other PFTs.

JULES_TRIFFID::harvest_freq_io
Type

integer(npft)

Permitted

>= 0

Default

none

Harvest freqency in years.

JULES_TRIFFID::harvest_ht_io
Type

real(npft)

Permitted

> 0

Default

none

Height [m] to which the PFT is reduced at each harvest cycle.

Note

lai_min_io must be set such that PFT height at lai_min_io <= harvest_ht_io, otherwise JULES will not start (the required value will be shown in error output).