Hard-wired vegetation types

[rml599gh]

An issue to start collecting cases where vegetation numbers are hard-wired or vegetation ordering is assumed.

subroutine um2cable_lp in cable_um_init_subrs.F90 appears to have a special case for permanent ice (confusingly called perma frost in the comment line). If I'm reading it correctly, this assumes ice is the last tile. I suspect it would be better to remove this special case from the code and just prepare ancillary files which have the values in that we want to use - I think this is mostly being used for soil ancillary fields.

[har917]

lakes

• lakes tile are typically hard-wired to 16 throughout the code base (#341)
• gw_hydro includes 3 instances where the condition veg%iveg .GE. 16 (or equivalently .GE. lakes_cable. This assumes the ordering will be lake, then ice.

vegetation

• cable_parameters includes a set of conditions linking the number of vegetation type (mytype) and tile index veg%iveg to determine the veg%deciduous flag

• cable_phenology includes conditions on veg%iveg to determine a number of behaviours

• cable_phenology assumes the tile order when determimning if summergreen crop (line 91)

• cbl_hyd_redistr uses %iveg to determine whether hydraulic redistribution can occur

phenology This needs a thorough review - there is clearly an assumption that relates the ordering of the phenology inputs to the vegetation type ordering - particularly impacts casa_inout and casa_readbiome

soil

• cable_roughness includes a link from iveg = 17 (ice) to roughness parameters (and hardwires soil type to isoilm = 9 a the same time)
• gw_hydro includes multiple cases of isoilm .EQ., isoilm .NE. etc. many of which are hard-wired
• cbl_snow_accum, cbl_snowMelt and cbl_snowDensity have conditions dependent on isoilm /= 9
• cbl_conductivity and cbl_oldConductivity have conditions dependent on isoilm .EQ. 9
• cable_carbon uses %isoilm as an index to a ancillary (line 295)
• %isoilm gets used through the coupled models to trigger whether to override the grid ancillary values or ice values for parameter values.
• isoilm is used in cable_canopy to switch to a JULES/MOSES for a coupling variable %gswx_T