meteo_tidy_ghcnd: Create a tidy GHCND dataset from a single monitor

Description

This function inputs an object created by ghcnd and cleans up the data into a tidy form.

Usage

meteo_tidy_ghcnd(
  stationid,
  keep_flags = FALSE,
  var = "all",
  date_min = NULL,
  date_max = NULL
)

Value

A data frame of daily weather data for a single weather monitor, converted to a tidy format. All weather variables may not exist for all weather stations. Examples of variables returned are:

id: Character string with the weather station site id
date: Date of the observation
prcp: Precipitation, in tenths of mm
tavg: Average temperature, in degrees Celsius
tmax: Maximum temperature, in degrees Celsius
tmin: Minimum temperature, in degrees Celsius
awnd: Average daily wind speed, in meters / second
wsfg: Peak gust wind speed, in meters / second

There are other possible weather variables in the Global Historical Climatology Network; see http://www1.ncdc.noaa.gov/pub/data/ghcn/daily/readme.txt for a full list. The variables prcp, tmax, tmin, and tavg

have all been converted from tenths of their metric to the metric (e.g., from tenths of degrees Celsius to degrees Celsius). All other variables are in the units specified in the linked file.

Arguments

stationid

(character) A character vector giving the identification of the weather stations for which the user would like to pull data. To get a full and current list of stations, the user can use the ghcnd_stations() function. To identify stations within a certain radius of a location, the user can use the meteo_nearby_stations() function.

keep_flags

TRUE / FALSE for whether the user would like to keep all the flags for each weather variable. The default is to not keep the flags (FALSE). See the note below for more information on these flags.

var

A character vector specifying either "all" (pull all available weather parameters for the site) or the weather parameters to keep in the final data (e.g., c("TMAX", "TMIN") to only keep maximum and minimum temperature). Example choices for this argument include:

PRCP: Precipitation, in tenths of millimeters
TAVG: Average temperature, in tenths of degrees Celsius
TMAX: Maximum temperature, in tenths of degrees Celsius
TMIN: Minimum temperature, in tenths of degrees Celsius

A full list of possible weather variables is available in NOAA's README file for the GHCND data (https://www1.ncdc.noaa.gov/pub/data/ghcn/daily/readme.txt). Most weather stations will only have a small subset of all the possible weather variables, so the data generated by this function may not include all of the variables the user specifies through this argument.

date_min

A character string giving the earliest date of the daily weather time series that the user would like in the final output. This character string should be formatted as "yyyy-mm-dd". If not specified, the default is to keep all daily data for the queried weather site from the earliest available date.

date_max

A character string giving the latest date of the daily weather time series that the user would like in the final output. This character string should be formatted as "yyyy-mm-dd". If not specified, the default is to keep all daily data for the queried weather site through the most current available date.

Author

Brooke Anderson brooke.anderson@colostate.edu

Examples

Run this code

if (FALSE) {
# One station in Australia is ASM00094275
meteo_tidy_ghcnd(stationid = "ASN00003003")
meteo_tidy_ghcnd(stationid = "ASN00003003", var = "tavg")
meteo_tidy_ghcnd(stationid = "ASN00003003", date_min = "1989-01-01")
}