R: Growing Season Length

climdex.gsl {climdex.pcic} | R Documentation

## Growing Season Length

### Description

This function computes the growing season length (GSL) given the input.

### Usage

    climdex.gsl(ci, gsl.mode = c("GSL", "GSL_first", "GSL_max", "GSL_sum"))

### Arguments

`ci` | Object of type climdexInput.
`gsl.mode` | Growing season length method to use.

### Details

This function takes a climdexInput object as input and computes the growing season length based on this data.

Growing season length as defined by the climdex indices is the number of days between the start of the first spell of warm days in the first half of the year, and the start of the first spell of cold days in the second half of the year. Spells of warm days are defined as six or more days with mean temperature above 5 degrees Celsius; spells of cold days are defined as six or more days with a mean temperature below 5 degrees Celsius.

The three alternate modes provided ('GSL_first', 'GSL_max', and 'GSL_sum') are for testing purposes only. They differ considerably from the first ('GSL') mode. All of them use a list of growing seasons – here defined as six or more consecutive days with a mean temperature greater than or equal to 5 degrees Celsius, followed by either the end of the year or six or more consecutive days with a mean temperature less than 5 degrees Celsius. 'GSL_first' returns the first growing season found; 'GSL_max' returns the longest growing season found; and 'GSL_sum' returns the total length of all growing seasons found.

### Value

A vector containing the number of days in the growing season for each year.

### Note

Note that fclimdex results may differ from results using the first ('GSL') mode due to bugs in fclimdex. Please ensure you are using the latest version of fclimdex, as there have been numerous bug fixes and the results should, at this point, match.

Please do not use the 'GSL_first', 'GSL_max', or 'GSL_sum' modes for anything other than testing purposes at this time, nor should you rely on this parameter being present in future versions of climdex.pcic.

### References

http://etccdi.pacificclimate.org/list_27_indices.shtml

### See Also

`growing.season.length`, `climdexInput.csv`.

### Examples

    library(PCICt)

    ## Create a climdexInput object from some data already loaded in and
    ## ready to go.

    ## Parse the dates into PCICt.
    tmax.dates <- as.PCICt(do.call(paste, ec.1018935.tmax[,c("year",
    "jday")]), format="%Y %j", cal="gregorian")
    tmin.dates <- as.PCICt(do.call(paste, ec.1018935.tmin[,c("year",
    "jday")]), format="%Y %j", cal="gregorian")
    prec.dates <- as.PCICt(do.call(paste, ec.1018935.prec[,c("year",
    "jday")]), format="%Y %j", cal="gregorian")

    ## Load the data in.
    ci <- climdexInput.raw(ec.1018935.tmax$MAX_TEMP,
    ec.1018935.tmin$MIN_TEMP, ec.1018935.prec$ONE_DAY_PRECIPITATION,
    tmax.dates, tmin.dates, prec.dates, base.range=c(1971, 2000))

    ## Create an annual timeseries of the growing season length in days.
    gsl <- climdex.gsl(ci)

[Package climdex.pcic version 1.1-11 Index]