Select data from the daily dataset

Select data from the daily dataset

Usage

ghcndSelect(
  gzfile,
  variable = c("TMIN", "TAVG", "TMAX"),
  station = NULL,
  qflag = "",
  verbose = TRUE,
  astype = as.integer
)

Arguments

gzfile

the local filename for the daily data file file. E.g. 2023.csv.gz from the daily GHCN data repository at NCEI-NOAA, at "https://www.ncei.noaa.gov/pub/data/ghcn/daily/by_year/". Please see the references bellow.

variable

string with the variable name(s) to be selected

station

string (vector) with the station(s) to be selected

qflag

a string with quality control flag(s)

verbose

logical indicating if progress is to be printed

astype

function to convert data to a class, default is set to convert the data to integer.

Value

if more than one variable, it returns an array whose dimentions are days, stations, variables. If one variable, then it returns a matrix whose dimentions are days, stations.

Details

The default selects TMIN, TAVG and TMAX and return it as integer because the original data is also integer with units in 10 Celcius degrees.

Warning

It can take time to execute if, for example, the data.table package is not available.

References

Menne, M., Durre, I., Vose, R., Gleason, B. and Houston, T. (2012) An overview of the global historical climatology network-daily database. Journal of Atmospheric and Oceanic Technology, 897–910.