Convenience functions

These are convenience functions to download, daily or monthly sea ice concentration data from the whole Antarctic or Arctic. For a more complete low level function, see cdr().

Usage

cdr_antarctic_monthly(
  date_range,
  variables = "aice",
  version = 5,
  file = NULL,
  dir = tempdir(),
  use_cache = TRUE
)

cdr_antarctic_daily(
  date_range,
  variables = "aice",
  version = 5,
  file = NULL,
  dir = tempdir(),
  use_cache = TRUE
)

cdr_arctic_monthly(
  date_range,
  variables = "aice",
  version = 5,
  file = NULL,
  dir = tempdir(),
  use_cache = TRUE
)

cdr_arctic_daily(
  date_range,
  variables = "aice",
  version = 5,
  file = NULL,
  dir = tempdir(),
  use_cache = TRUE
)

Arguments

date_range

Vector of size two with the start and end dates. Supported formats are:

• A Date or POSIXct/POSIXlt object.

• A character vector with ISO format dates: c("2020-01-01", "2020-12-31")

• A character vector with year-month: c("2020-01", "2020-06") (expands to first/last day of month).

• A character vector with year only: c("2020", "2021") (expands to full year).

variables

Character vector with the variables to fetch. Valid values are

qa

Quality control flag.

stdev

Sea ice standard deviation.

interpolation_spatial

Flag for spatial interpolation.

interpolation_temporal

Flag for temporal interpolation.

aice_bt

Sea ice concentration of the Bootstrap method.

aice_nt

Sea ice concentration of the Nasa Team method.

Although not all variables are available in all versions and all resolutions. The *_nt and *_bt variables are only available in version 4 and the interpolation flags are only available for daily values.

version

Version of the dataset. Can be 4 or 5.

file

Character with the file name to use for download. If NULL, the file name will be constructed by hashing the request URL. Requests consisting in more than one file will append a number.

dir

Directory where to download the file.

use_cache

Logical indicating whether to not perform the download if the file already exist.

Value

A string vector with the location of the downloaded files

Examples

if (FALSE) { # \dontrun{
cdr_antarctic_monthly(c("2022-01", "2022-01"))
} # }