Backup USDA SNOTEL

backup_snotel.R

# This tiny script tries to grab all USDA SNOTEL data
# for safekeeping. SNOTEL monitors snow and water across
# the US but mostly in the west.
# https://www.nrcs.usda.gov/resources/data-and-reports/snow-and-water-interactive-map
#
# The data downloaded are the historical reports
# summarizing daily values of snow pack and additional
# metrics. Reports lag real-time values with a couple
# of weeks.
#
#---------------------------------------------------------#

# loads required libraries
library(snotelr)
library(dplyr)

# lists all sites
sites <- snotel_info()

# download loop
# could be parallelized but
# might trigger a rate limiter
# so be careful with parApply()
# if you implement it
snotel_data <- lapply(
  sites$site_id,
  function(id){
  tryCatch(
    expr = snotel_download(
      site_id = id,
      internal = TRUE
      ),
    error = function(e){return(NULL)}
    )
  }
)

# One can flatten everything, this results
# into a table of 12M rows and 19 columns
# ~2.5GB in size
snotel_data <- bind_rows(snotel_data)

# save as RDS and compress
# to reduce the file size
# compressed ~50MB
saveRDS(
  snotel_data,
  "snotel_backup.rds",
  compress = "xz"
)