Search code examples
raggregaterastertiffnetcdf

Downloading WorldPop Population Count rasters

I am interested in downloading the 2020 UN Adjusted Population Count for Democratic Republic of the Congo at the 30 arc second resolution from WorldPop (See here ) as a GeoTIFF (.tif) file. I am trying to do this for multiple countries to I was exploring the wpgpDownloadR package.

devtools::install_github("wpgp/wpgpDownloadR")
library(wpgpDownloadR)
wpgpListCountryDatasets(ISO3="COD")

Could I get some help with directly downloading the WorldPop Population Count .tif file for a specific country (for example, DRC, Nigeria, Belgium, France etc.)?

I have an R code for converting this GeoTIFF raster (.tif file) to a NetCDF (.nc file) if I already have the tif file locally pre-downloaded but if I want for a different country I have to download it and do this over again.

library(raster)

# Downloaded from above website
DRCWorldPop <- raster("cod_ppp_2020_1km_Aggregated_UNadj.tif") 

rnc <- writeRaster(DRCWorldPop, filename ='DRC_0000.nc', format = "CDF",  varname = "Susceptible", varunit = "Persons", longname = "Susceptible", overwrite = TRUE)

I am trying to have a single generic code to use ftp to download the rasters for any country. Could you please point me in the right direction? Thank you for your time.

Solution

  • You can do something like this

    library(raster)
library(wpgpDownloadR)

iso3 <- "RWA"
cov <- "ppp_2000"
path <- dirname(tempdir())

f <- file.path(path, tolower(paste0(iso3, "_", cov, ".tif")))
if (!file.exists(f)) {
    f <- wpgpGetCountryDataset(ISO3 = "RWA", covariate = "ppp_2000", destDir=path) 
}
r <- raster(f)

    This allows you to loop over country and covariate. It also avoids downloading files that you already have.