all_spei: all_spei

In seschaub/getSpei: getSpei converting SPEI netCDF files to R data frames. R package.

Description

all_spei converts SPEI netCDF files of the Global SPEI database into a data frame, which comprises global SPEI data. This function allows to set a specific start and end year. Note that this function is based on SPEI data, which starts in 1901 (current standard).For extracting SPEI data over time for specific (multiple) locations the function spec_spei can be used.

Usage

all_spei(spei_files, start_y, end_y)

Arguments

spei_files	spei_files is a vector of strings. The strings are the SPEI netCDF filenames without filename extensions (i.e. .nc). netCDF files need to be downloaded from the Global SPEI database before using this function.
start_y	start_y indicates the first year requested of the SPEI data.
end_y	end_y indicates the last year requested of the SPEI data.

Note

The function returns the variables: lon: longitude. lat: latitude. year: respective year month: respective month speixx: respective spei

Some initial ideas for the function are based on a work from Bartlein P. J. (R for Earth-System Science).

SPEI values should be compared with values available in the SPEI Global Drought Monitor

Author(s)

Sergei Schaub, ETH Zürich, Agricultural Economics and Policy Group & Grassland Sciences Group

Please cite the package as: Schaub, S. (2019) getSpei: converting SPEI netCDF files to R data frames. R package. Version 3.4.19

References

Beguería, S., Latorre, B., Reig, F. & Vicente-Serrano, S.M. (2019) The Standardised Precipitation-Evapotranspiration Index (http://spei.csic.es/index.html)

See Also

all_spei_viz, spec_spei

Examples

# set working directory to directory where speixx.nc files are stored: 
workdir <- "H:/folder1/folder2"
setwd(workdir)

# run function:
d1 <- all_spei(spei_files = c("spei01","spei06","spei12"), start_y = 2003, end_y = 2004)

For a complete demonstration of this package, refer to getSpei website

seschaub/getSpei documentation built on May 5, 2019, 8:16 a.m.