precip.dep {seas}R Documentation

Cumulative precipitation departure

Description

Calculate the cumulative precipitation departure (CPD) for a station with a given precipitation normal.

Usage

precip.dep(dat, norm, id)

Arguments

dat data.frame of climate data
norm precip.norm object containing the precipitation normal for the same station as dat
id unique station identifier used to extract a subset of data from dat; if missing will use norm$id (if it exists)

Details

This function is useful for looking at the behavior of a precipitation time-series in relation to its precipitation normal over an extended period of time. This is especially useful for identifying changes in precipitation, and is useful for relating to groundwater recharge patterns (i.e. http://wlapwww.gov.bc.ca/rfc/river_forecast/grwater/obsw002.html).

Value

Returns a data.frame with year, jday, date, precip, and dep fields.

Note

The selection of fun in precip.norm will affect the result of this function; width has a small effect.

Periods with missing (NA) values in dat$precip will have a flat departure, neither increasing nor decreasing.

Author(s)

M.W. Toews

References

Hodge, W.S., 2001, A Preliminary Survey of Methyl Tertiary-Butyl Ether (MTBE) in Groundwater at Selected Well Sites in British Columbia, Canada, Groundwater Section, Water Protection Branch, Ministry of Water, Land and Air Protection.

See Also

precip.norm

Examples

data(mscstn)
data(mscdata)

d <- mksub(mscdata, id=1108447, rm.id=FALSE)
d.ss <- seas.sum(d)
d.dep <- precip.dep(d,precip.norm(d.ss,fun="mean"))
plot(dep ~ date, d.dep, type="l", main="CPD from mean normals")

d.dep <- precip.dep(d, precip.norm(d.ss,fun="median"))
plot(dep ~ date, d.dep, type="l", main="CPD from median normals")

[Package seas version 0.2-1 Index]