Spatial objective Lamb Weather Type Classification

Calculates the automatic Lamb or Jenkinson and Collison classification at each grid point. The approach details are described in lamb_clas.

Usage

spatial_lamb(
  msl,
  xmin = -180,
  xmax = 180,
  ymin = -80,
  ymax = 80,
  U = T,
  thr = c(6, 6),
  cores = 1
)

Arguments

msl

Mean Sea Level pressure gridded data.

xmin

minimum longitude

xmax

maximum longitude

ymin

minimum latitude

ymax

maximum longitude

U

Logical. If T, Jones et al. 2013 approach is applied, maintaining the U-type in the classification. If F, U is removed as detailed in Trigo and DaCamara, 2000.

thr

threshold used for Unclassified days (total shear vorticity and total flow, respectively). Default c(6,6).

cores

Number of cores to be used

Value

A list with:

• A data frame containing the gridded classification

References

Jenkinson, A.F., Collison F.P (1977) An initial climatology of gales over the North Sea Synoptic Climatology Branch Memorandum, No. 62.Meteorological Office: Bracknell, England.Jones, P. D., Hulme M., Briffa K. R. (1993) A comparison of Lamb circulation types with an objective classification scheme Int. J. Climatol. 13: 655–663.Jones, P. D., Harpham C, Briffa K. R. (2013) Lamb weather types derived from Reanalysis products Int. J. Climatol. 33: 1129–1139.

Trigo, R., DaCamara C. (2000) Circulation weather types and their impact on the precipitation regime in Portugal Int. J. Climatol. 20: 1559-1581.

See also

lamb_clas

Examples

library(dplyr)
#> 
#> Attaching package: 'dplyr'
#> The following objects are masked from 'package:stats':
#> 
#>     filter, lag
#> The following objects are masked from 'package:base':
#> 
#>     intersect, setdiff, setequal, union
data(msl)

msl <- filter(msl, time >= "2000-01-01", time <= "2000-03-30")
clas <- spatial_lamb(msl, xmin = 5,xmax = 15, ymin = 40, ymax = 50, cores = 1)