Download MODIS product files — download

Need maintenance for the directory path change in NASA EOSDIS. This function first retrieves the all hdf download links on a certain day, then only selects the relevant tiles from the retrieved links. Download is only done at the queried horizontal-vertical tile number combinations. An exception is MOD06_L2 product, which is produced every five minutes every day.

Usage

download_modis(
  product = c("MOD09GA", "MOD11A1", "MOD06_L2", "MCD19A2", "MOD13A2", "VNP46A2"),
  version = "61",
  horizontal_tiles = c(7, 13),
  vertical_tiles = c(3, 6),
  mod06_links = NULL,
  nasa_earth_data_token = NULL,
  date = c("2023-09-01", "2023-09-01"),
  directory_to_save = NULL,
  acknowledgement = FALSE,
  download = FALSE,
  remove_command = FALSE,
  hash = FALSE
)

Arguments

product: character(1). One of c("MOD09GA", "MOD11A1", "MOD06_L2", "MCD19A2", "MOD13A2", "VNP46A2")
version: character(1). Default is "61", meaning v061.
horizontal_tiles: integer(2). Horizontal tile numbers c({start}, {end}). Default is c(7, 13).
vertical_tiles: integer(2). Vertical tile numbers c({start}, {end}). Default is c(3, 6).
mod06_links: character(1). CSV file path to MOD06_L2 download links from NASA LAADS MOD06_L2. Default is NULL.
nasa_earth_data_token: character(1). Token for downloading data from NASA. Should be set before trying running the function.
date: character(1 or 2). length of 10. Date or start/end dates for downloading data. Format "YYYY-MM-DD" (ex. January 1, 2018 = "2018-01-01"). Note: ignored if product == "MOD06_L2".
directory_to_save: character(1). Directory to save data.
acknowledgement: logical(1). By setting TRUE the user acknowledges that the data downloaded using this function may be very large and use lots of machine storage and memory.
download: logical(1). Download data or only save wget commands.
remove_command: logical(1). Remove (TRUE) or keep (FALSE) the text file containing download commands.
hash: logical(1). By setting TRUE the function will return an rlang::hash_file() hash character corresponding to the downloaded files. Default is FALSE.

Value

For hash = FALSE, NULL
For hash = TRUE, an rlang::hash_file character.
HDF (.hdf) files will be stored in year/day_of_year sub-directories within directory_to_save.

Note

Both dates in date should be in the same year. Directory structure looks like input/modis/raw/{version}/{product}/{year}/{day_of_year}.

References

data_mcd19a22021amadeus

data_mod06l2_2017amadeus

data_mod09ga2021amadeus

data_mod11a12021amadeus

data_mod13a22021amadeus

article_roman2018vnp46amadeus

Author

Mitchell Manware, Insang Song

Examples

if (FALSE) { # \dontrun{
## NOTE: Examples are wrapped in `/dontrun{}` to avoid sharing sensitive
##       NASA EarthData tokden information.
# example with MOD09GA product
download_modis(
  product = "MOD09GA",
  version = "61",
  horizontal_tiles = c(8, 8),
  vertical_tiles = c(4, 4),
  date = "2024-01-01",
  nasa_earth_data_token = "./pathtotoken/token.txt",
  directory_to_save = tempdir(),
  acknowledgement = TRUE,
  download = FALSE, # NOTE: download skipped for examples,
  remove_command = TRUE
)
# example with MOD06_L2 product
download_modis(
  product = "MOD06_L2",
  version = "61",
  horizontal_tiles = c(8, 8),
  vertical_tiles = c(4, 4),
  date = "2024-01-01",
  mod06_links =
    system.file(
      "extdata", "nasa", "LAADS_query.2024-08-02T12_49.csv",
      package = "amadeus"
    ),
  nasa_earth_data_token = "./pathtotoken/token.txt",
  directory_to_save = tempdir(),
  acknowledgement = TRUE,
  download = FALSE, # NOTE: download skipped for examples,
  remove_command = TRUE
)
# example with VNP46A2 product
download_modis(
  product = "VNP46A2",
  version = "61",
  horizontal_tiles = c(8, 8),
  vertical_tiles = c(4, 4),
  date = "2024-01-01",
  nasa_earth_data_token = "./pathtotoken/token.txt",
  directory_to_save = tempdir(),
  acknowledgement = TRUE,
  download = FALSE, # NOTE: download skipped for examples,
  remove_command = TRUE
)
} # }