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Download MODIS product files

Source: R/download.R
download_modis.Rd

Downloads MODIS data using httr2 with robust retry logic and rate limiting. This function queries NASA's CMR API for available granules and downloads relevant tiles based on the specified extent.

Usage

download_modis(
  product = c("MOD09GA", "MYD09GA", "MOD09GQ", "MYD09GQ", "MOD09A1", "MYD09A1",
    "MOD09Q1", "MYD09Q1", "MOD11A1", "MYD11A1", "MOD11A2", "MYD11A2", "MOD11B1",
    "MYD11B1", "MOD13A1", "MYD13A1", "MOD13A2", "MYD13A2", "MOD13Q1", "MYD13Q1",
    "MOD13A3", "MYD13A3", "MCD12Q1", "MOD14A1", "MYD14A1", "MOD14A2", "MYD14A2",
    "MOD14CM1", "MYD14CM1", "MOD16A2", "MYD16A2", "MCD64A1", "MCD64CMQ", "MOD06_L2",
    "MCD14ML", "MCD19A2", "VNP46A2", "VNP64A1"),
  version = "061",
  nasa_earth_data_token = NULL,
  date = c("2023-09-01", "2023-09-01"),
  extent = c(-125, 22, -64, 50),
  directory_to_save = NULL,
  acknowledgement = FALSE,
  download = TRUE,
  remove_command = FALSE,
  show_progress = TRUE,
  hash = FALSE,
  max_tries = 20,
  rate_limit = 2
)

Arguments

product

character(1). MODIS product code

version

character(1). Default is "061", meaning v061.

nasa_earth_data_token

character(1) or NULL. NASA EarthData authentication token. For security, recommended options (in priority order):

  • NULL (default): Reads from NASA_EARTHDATA_TOKEN environment variable

  • File path: e.g., "~/.nasa_earthdata_token"

  • Token string: Direct token (not recommended for scripts)

Use setup_nasa_token() for interactive setup.

date

character(1 or 2). Date range "YYYY-MM-DD" format

extent

numeric(4). Bounding box c(min_lon, max_lon, min_lat, max_lat). Default covers continental US: c(-125, 22, -64, 50).

directory_to_save

character(1). Directory to save data.

acknowledgement

logical(1). Must be TRUE to proceed with download

download

logical(1). DEPRECATED. Downloads now happen automatically. Set to FALSE to skip downloading (generates file list only).

remove_command

logical(1). Deprecated, ignored.

show_progress

logical(1). Show download progress (default TRUE)

hash

logical(1). Return hash of downloaded files (default FALSE)

max_tries

integer(1). Maximum download retry attempts (default 20)

rate_limit

numeric(1). Minimum seconds between requests (default 2)

Value

invisible list with download results; or hash character if hash=TRUE

Note

Due to NASA data access policies, downloads require a valid NASA Earthdata token for authentication. For security, it's recommended to store your token in an environment variable or file rather than in your code. Use setup_nasa_token() for easy, secure token setup.

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

References

Lyapustin A, Wang Y (2022). “MODIS/Terra+Aqua Land Aerosol Optical Depth Daily L2G Global 1km SIN Grid V061.” doi:10.5067/MODIS/MCD19A2.061 . https://www.earthdata.nasa.gov/data/catalog/lpcloud-mcd19a2-061. MODIS Atmosphere Science Team (2017). “MODIS/Terra Clouds 5-Min L2 Swath 1km and 5km.” doi:10.5067/MODIS/MOD06_L2.061 . https://ladsweb.modaps.eosdis.nasa.gov/missions-and-measurements/products/MOD06_L2. Vermote E, Wolfe R (2021). “MODIS/Terra Surface Reflectance Daily L2G Global 1km and 500m SIN Grid V061.” doi:10.5067/MODIS/MOD09GA.061 . https://www.earthdata.nasa.gov/data/catalog/lpcloud-mod09ga-061. Wan Z, Hook S, Hulley G (2021). “MODIS/Terra Land Surface Temperature/Emissivity Daily L3 Global 1km SIN Grid V061.” doi:10.5067/MODIS/MOD11A1.061 . https://www.earthdata.nasa.gov/data/catalog/lpcloud-mod11a1-061. Didan K (2021). “MODIS/Terra Vegetation Indices 16-Day L3 Global 1km SIN Grid V061.” doi:10.5067/MODIS/MOD13A2.061 . https://www.earthdata.nasa.gov/data/catalog/lpcloud-mod13a2-061. Román MO, Wang Z, Sun Q, Kalb V, Miller SD, Molthan A, Schultz L, Bell J, Stokes EC, Pandey B, Seto KC, Hall D, Oda T, Wolfe RE, Lin G, Golpayegani N, Devadiga S, Davidson C, Sarkar S, Praderas C, Schmaltz J, Boller R, Stevens J, Ramos González OM, Padilla E, Alonso J, Detrés Y, Armstrong R, Miranda I, Conte Y, Marrero N, MacManus K, Esch T, Masuoka EJ (2018). “NASA's Black Marble nighttime lights product suite.” Remote Sensing of Environment, 210, 113–143. ISSN 00344257. doi:10.1016/j.rse.2018.03.017 . https://linkinghub.elsevier.com/retrieve/pii/S003442571830110X.

Author

Mitchell Manware, Insang Song

Examples

if (FALSE) { # \dontrun{
# RECOMMENDED: Set up token once (persists across sessions)
setup_nasa_token()

# Then download without specifying token
download_modis(
  product = "MOD09GA",
  version = "061",
  date = "2024-01-01",
  extent = c(-80, 35, -75, 40),
  directory_to_save = tempdir(),
  acknowledgement = TRUE
)

# ALTERNATIVE: Token from file
download_modis(
  product = "MOD09GA",
  version = "061",
  date = "2024-01-01",
  extent = c(-80, 35, -75, 40),
  nasa_earth_data_token = "~/.nasa_earthdata_token",
  directory_to_save = tempdir(),
  acknowledgement = TRUE
)

# ALTERNATIVE: Set token for current session
Sys.setenv(NASA_EARTHDATA_TOKEN = "your_token_here")
download_modis(
  product = "MOD09GA",
  date = "2024-01-01",
  acknowledgement = TRUE
)

# Date range
download_modis(
  product = "MOD09GA",
  version = "061",
  date = c("2024-01-01", "2024-01-07"),
  extent = c(-80, 35, -75, 40),
  directory_to_save = tempdir(),
  acknowledgement = TRUE
)
} # }