pci {ClimInd}

Precipitation Concentration Index

Description

Index to evaluate precipitation heterogeneity at a monthly scale. Values <10 (uniform monthly rainfall distribution); values 11-15 (moderate concentration of precipitation); values 16-20 (irregular distribution); and >20 ((high precipitation concentration)

Usage

pci(data, data_names = NULL, na.rm = FALSE, ...)

Arguments

data

daily precipitation, mm

data_names

names of each period of time

na.rm

logical. Should missing values (including NaN) be removed?

...

further arguments passed to or from other methods

Value

index value

Formula

PCI = \frac{\sum_{i=1}^{12} P_i ^ 2} {(P_t) ^ 2} * 100

References

Oliver, J.E. (1980) Monthly precipitation distribution: a comparative index. Professional Geographer, 32, 300–309

Examples

data(data_all)
pci(data = data_all$rr)