Significant Hail Parameter — SHIP • MeteoMate

the function estimate SHIP index according to NOAA.

Usage

SHIP(
  ta_s,
  hus_s,
  zg_s,
  pa_s,
  ua_s,
  va_s,
  ta_pl,
  hus_pl,
  zg_pl,
  pa_pl,
  ua_pl,
  va_pl,
  dp = 300,
  vtc = TRUE,
  nthreads = 1
)

Arguments

ta_s: air temperature [lon, lat, time] at 2m above the surface(K).
hus_s: specific humidity [lon, lat, time] at 2m above the surface (kg/kg).
zg_s: surface geopotential [lon, lat] (m^2/s^2).
pa_s: surface pressure [lon, lat, time] (hPa).
ua_s: 10 metre zonal wind component [lon, lat, time] (m/s).
va_s: 10 metre meridional wind component [lon, lat, time] (m/s).
ta_pl: air temperature [lon, lat, lev, time] on pressure level (K).
hus_pl: specific humidity [lon, lat, lev, time] on pressure level (kg/kg).
zg_pl: geopotential [lon, lat, lev, time] on pressure level (m^2/s^2).
pa_pl: pressure profile [lev] in ascending order from the TOA to the surface (hPa).
ua_pl: zonal wind component [lon, lat, lev, time] on pressure level (m/s).
va_pl: meridional wind component [lon, lat, lev, time] on pressure level (m/s).
dp: height of the layer (m) to search for parcel with the most unstable CAPE. Default is 3000 km
vtc: logical refers to virtual temperature correction due to Doswell and Rasmussen (1994).
nthreads: an integer specifying the number of threads to use for computation (OpenMP). Default is 1.

Value

the computed SHIP.

References

Doswell III, C. A., & Rasmussen, E. N. (1994). The effect of neglecting the virtual temperature correction on CAPE calculations. Weather and forecasting, 9(4), 625-629 doi:10.1175/1520-0434(1994)009<0625:TEONTV>2.0.CO;2 .

Examples

data("ERA5_sfc")
ta_s <- ERA5_sfc$t2m
td_s <- ERA5_sfc$t2d
pa_s <- ERA5_sfc$sp / 100
hus_s <- hus_from_td(td_s, pa_s)
dim(hus_s) <- dim(td_s)
zg_s <- ERA5_sfc$z[, , 1]
ua_s <- ERA5_sfc$u10
va_s <- ERA5_sfc$v10

data("ERA5_pl")
ta_pl <- ERA5_pl$ta
hus_pl <- ERA5_pl$hus
pa_pl <- ERA5_pl$plev / 100
zg_pl <- ERA5_pl$z
ua_pl <- ERA5_pl$ua
va_pl <- ERA5_pl$va
dp <- 300.0

res <- SHIP(
  ta_s, hus_s,
  zg_s, pa_s,
  ua_s, va_s,
  ta_pl, hus_pl,
  zg_pl, pa_pl,
  ua_pl, va_pl,
  dp
)