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Adjust Crop Parameters Table using AgERA5 Climate Data

Source: R/kc_adjust.R
wapor_adjust_crop_params_agera5.Rd

Automatically computes growth stage windows for each crop class and updates kc_mid and kc_end in a crop parameters data frame using stage-specific mean climate parameters from AgERA5.

Usage

wapor_adjust_crop_params_agera5(
  crop_params,
  aoi = NULL,
  season_start,
  season_end,
  climate_df = NULL,
  method_rh = c("hourly_rh", "tmin_tmax")
)

Arguments

crop_params

data.frame of crop parameters. Must contain columns: kc_ini, kc_mid, kc_end, l_ini_days, l_mid_days, l_late_days. May also contain class_value, class_name, max_height_m (or height_m).

aoi

Region spatial object (sf polygon, bbox, or file path). Required if climate_df is not provided.

season_start

Date or character "YYYY-MM-DD". Season start date.

season_end

Date or character "YYYY-MM-DD". Season end date.

climate_df

Optional data.frame of pre-extracted climate records with columns date, u2, and rh_min (as returned by wapor_extract_agera5_climate()). If provided, aoi is not queried.

method_rh

Method for relative humidity: "hourly_rh" or "tmin_tmax".

Value

An updated crop_params data.frame with:

kc_mid

Updated climatically adjusted Kc_mid

kc_end

Updated climatically adjusted Kc_end

kc_mid_tab

Preserved original tabulated Kc_mid

kc_end_tab

Preserved original tabulated Kc_end

u2_mid

Mean wind speed during mid-season (m/s)

rh_min_mid

Mean minimum RH during mid-season (%)

u2_late

Mean wind speed during late-season (m/s)

rh_min_late

Mean minimum RH during late-season (%)

Examples

# Prepare synthetic climate data
dates <- seq.Date(as.Date("2023-01-01"), as.Date("2023-04-30"), by = "day")
clim <- data.frame(
  date = dates,
  u2 = 3.5, # breezy
  rh_min = 28 # dry
)

crop_df <- data.frame(
  class_value = 1,
  class_name = "Wheat",
  kc_ini = 0.40,
  kc_mid = 1.15,
  kc_end = 0.30,
  l_ini_days = 30L,
  l_mid_days = 40L,
  l_late_days = 30L,
  max_height_m = 1.0
)

adj_crop_df <- wapor_adjust_crop_params_agera5(
  crop_params = crop_df,
  season_start = "2023-01-01",
  season_end = "2023-04-30",
  climate_df = clim
)
adj_crop_df
#>   class_value class_name kc_ini kc_mid kc_end l_ini_days l_mid_days l_late_days
#> 1           1      Wheat    0.4  1.242    0.3         30         40          30
#>   max_height_m kc_mid_tab kc_end_tab u2_mid rh_min_mid u2_late rh_min_late
#> 1            1       1.15        0.3    3.5         28     3.5          28