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Potential Instability Index

Potential_instability_index.Rd

It calculates the potential instability of the atmospheric layer between 925 and 500 hPa.

Usage

Potential_instability_index(
  hus925,
  ta925,
  z925,
  hus500,
  ta500,
  z500,
  nthreads = 1
)

Arguments

hus925

specific humidity [lon, lat, time] at 925 hPa (kg/kg).

ta925

air temperature [lon, lat, time] at 925 hPa (K).

z925

geopotential height [lon, lat, time] at 925 hPa (m).

hus500

specific humidity [lon, lat, time] at 500 hPa (kg/kg).

ta500

air temperature [lon, lat, time] at 500 hPa (K).

z500

geopotential height [lon, lat, time] at 500 hPa (m).

nthreads

an integer specifying the number of threads to use for computation (OpenMP). Default is 1.

Value

the computed Potential Instability Index (K/m).

References

Van Delden, A., 2001. The synoptic setting of thunderstorms in Western Europe. Atmos. Res. 56, 89–110.

Examples

data("ERA5_pl")
pa <- ERA5_pl$plev / 100 # convert to hPa
hus <- ERA5_pl$hus
ta <- ERA5_pl$ta
z <- ERA5_pl$z / 9.80665 # convert to m
l500 <- which(pa == 500)
l925 <- which(pa == 925)
res <- Potential_instability_index(
  hus[, , l925, ],
  ta[, , l925, ],
  z[, , l925, ],
  hus[, , l500, ],
  ta[, , l500, ],
  z[, , l500, ]
)