Load WRF model run data

Source: R/wrf_load.R

Loads WRF model run data as a raster package RasterBrick. If the specified data does not exist on the user's machine, then it will try to be downloaded from the AirFire database.

On 2020-09-03, available model identifiers include the following:

  • PNW-1.33km

  • PNW-4km

Some useful variables provided by WRF:

  • XLONG - Longitude (degrees East)

  • XLAT - Latitude (degrees North)

  • XLONG_U - Longitude (degrees East)

  • XLAT_U - Latitude (degrees North)

  • XLONG_V - Longitude (degrees East)

  • XLAT_V - Latitude (degrees North)

  • U - Wind X component (m/s)

  • V - Wind Y component (m/s)

  • W - Wind Z component (m/s)

  • U10 - Wind X component at 10 meters (m/s)

  • V10 - Wind Y component at 10 meters (m/s)

  • ZNU - eta values on half (mass) levels

  • ZNW - eta values on full (w) levels

  • LU_INDEX - Land use category

  • Q2 - QV at 2 M (kg)

  • T - Perturbation potential temperature theta-t0 (K)

  • T2 - Temperature at 2 meters (K)

  • TH2 - Potential temperature at 2 meters (K)

  • HGT - Terrain height (m)

  • RAINNC - Accumulated total grid scale precipitation (mm)

  • CFRACT - Total cloud fraction

  • PBLH - Planetary boundary layer height (m)

wrf_load(
  modelName = NULL,
  modelRun = NULL,
  modelRunHour = NULL,
  baseUrl = "http://m2.airfire.org",
  localPath = NULL,
  varNames = NULL,
  res = NULL,
  xlim = NULL,
  ylim = NULL,
  verbose = TRUE
)

Arguments

modelName

Model identifier.
modelRun

Model initialization timestamp as "YYYYMMDDHH".
modelRunHour

Hour forecasted from initial time, i.e. 7.
baseUrl

Base URL for WRF output.
localPath

Absolute path to a NetCDF file not found in `WRFDataDir`.
varNames

WRF variable(s) to load. If NULL, the following subset specified by AirFire will be loaded: XLONG, XLAT, XLONG_U, XLAT_U, XLONG_V, XLAT_V, U, V, U10, V10, ZNU, ZNW, LU_INDEX, Q2, T, T2, TH2, HGT, RAINNC, CFRACT, and PBLH.
res

Resolution of raster in degrees.
xlim

A vector of coordinate longitude bounds.
ylim

A vector of coordinate latitude bounds.
verbose

Logical to display messages.

Value

A raster package RasterBrick object.

Examples

# \donttest{
library(AirFireWRF)
setWRFDataDir("~/Data/WRF")

raster <- wrf_load(
  modelName = "PNW-4km",
  modelRun = "2020082612",
  modelRunHour = 9,
  varNames = c("HGT", "TSK", "U10", "V10"),
  res = 0.1,
  xlim = c(-125, -116),
  ylim = c(45, 50)
)
#> Warning: multiple methods tables found for ‘wkt’

print(raster)
#> class      : RasterBrick 
#> dimensions : 51, 91, 4641, 4  (nrow, ncol, ncell, nlayers)
#> resolution : 0.1001554, 0.1000347  (x, y)
#> extent     : -125.0784, -115.9642, 44.99589, 50.09766  (xmin, xmax, ymin, ymax)
#> crs        : +proj=longlat +datum=WGS84 +ellps=WGS84 +towgs84=0,0,0 
#> source     : memory
#> names      :         HGT,         TSK,         U10,         V10 
#> min values :    0.000000,  276.636688,   -3.233186,  -10.490043 
#> max values : 2436.073059,  315.662526,    8.301670,    5.910079 
#> 
# }