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Build grazable grass availability from an LPJmL run.

Source: R/feed_lpjml.R
build_grass_availability_lpjml.Rd

Reads managed-grassland net primary production/availability (the LPJmL grassland CFT) from the pinned WHEP artifact by default. Pass availability or availability_path to use a custom already-derived artifact; pass run_dir to read a finished local LPJmL run instead and convert NPP to grazable above-ground dry-matter availability, the forage supply ceiling for feed allocation. Availability is the production flux, not the realised grazing off-take (the off-take is the intake-validation target, not the supply).

Usage

build_grass_availability_lpjml(
  run_dir = NULL,
  years = NULL,
  first_year = 1901L,
  shares = grass_access_shares(),
  example = FALSE,
  availability = NULL,
  availability_path = NULL
)

Arguments

run_dir

Path to the LPJmL run output directory holding pft_npp.nc and cftfrac.nc (the scenario_* output folder). If unset, the pinned lpjml-grass-availability artifact is used.

years

Integer vector of calendar years to read.

first_year

First calendar year of the run's output time axis.

shares

Accessibility and conversion parameters from grass_access_shares().

example

If TRUE, return a small fixture instead of reading a run.

availability

Optional already-derived grass availability tibble/data frame. Takes precedence over pinned data and run_dir.

availability_path

Optional path to an already-derived grass availability artifact (.parquet, .csv, or .rds). Takes precedence over pinned data and run_dir.

Value

A tibble with lon, lat, year, grass_npp_gc_m2, grass_avail_dm_t_ha and grass_avail_dm_t.

Examples

build_grass_availability_lpjml(example = TRUE)
#> # A tibble: 3 × 6
#>      lon    lat  year grass_npp_gc_m2 grass_avail_dm_t_ha grass_avail_dm_t
#>    <dbl>  <dbl> <int>           <dbl>               <dbl>            <dbl>
#> 1   9.25  47.8   2000            612.                6.26            16980
#> 2 -55.2  -12.2   2000            488.                4.99            15640
#> 3  35.8   -1.25  2000            422.                4.31            13110