Downloads and processes GHS-WUP-DEGURBA (World Urbanization Prospects - Degree of Urbanisation) data, which provides global urbanization levels classified according to the Degree of Urbanisation methodology. The function extracts multi-temporal raster files and formats them for compatibility with PRIO-GRID temporal structure.
Details
GHS-WUP-DEGURBA provides urbanization classification at 1 km spatial resolution for multiple time periods globally. This function:
Downloads zipped GHS-WUP-DEGURBA raster files from the data repository
Extracts TIF files from zip archives (cached to avoid repeated extraction)
Loads and combines multiple raster layers into a single multi-temporal raster
Standardizes layer names using PRIO-GRID date format for consistency
Provides urbanization classification data at 5-year intervals (typically 1975-2030)
The DEGURBA classification uses the following codes:
30: Urban centres (cities)
23: Dense urban cluster
22: Semi-dense urban cluster
21: Suburban or peri-urban
13: Rural cluster
12: Low density rural
11: Very low density rural
10: Water bodies or uninhabited areas
Note
Files are automatically extracted from zip archives and cached locally
The function handles large files and may take time for initial download
Classification includes both observed and modeled/projected values
Temporal alignment uses PRIO-GRID month/day conventions for consistency
References
Schiavina M, Melchiorri M, Pesaresi M, Jacobs-Crisioni C, Dijkstra L (2025). “GHS-WUP-DEGURBA R2025A – GHS-WUP DEGURBA Settlement Layers, Application of the Degree of Urbanisation Methodology (Stage I) to GHS-WUP-POP R2025A, Multitemporal (1975-2100).” doi:10.2905/1c049178-ab00-4bbc-b638-3e3c19daaacb .
European Commission, Statistical Office of the European Union (2021). “Applying the Degree of Urbanisation — A Methodological Manual to Define Cities, Towns and Rural Areas for International Comparisons.” doi:10.2785/706535 .
Jacobs-Crisioni C, Schiavina M, Alessandrini A, Dijkstra L (2025). “Population by Degree of Urbanization and by Urban Agglomeration from 1950 to 2100.” https://publications.jrc.ec.europa.eu/repository/handle/JRC144219. doi:10.2760/1419546 , 2025-12-18.
Examples
if (FALSE) { # \dontrun{
# Read GHS-WUP-DEGURBA data
# Warning: This involves large file downloads and processing
degurba <- read_ghs_wup_degurba()
# Examine the structure
print(degurba)
# View available time periods
time_periods <- names(degurba)
print(time_periods)
# Plot urbanization classification for specific year
terra::plot(degurba[["2020-12-31"]],
main = "Global Urbanization Classification 2020")
# Compare urbanization change over time
urban_1990 <- degurba[["1990-12-31"]]
urban_2020 <- degurba[["2020-12-31"]]
terra::plot(urban_2020 - urban_1990,
main = "Urbanization Change 1990-2020")
# Extract urbanization for specific region (example: crop to extent)
# asia_extent <- terra::ext(60, 140, -10, 50)
# asia_urban <- terra::crop(degurba, asia_extent)
# terra::plot(asia_urban[[nlyr(asia_urban)]], main = "Asia Urbanization")
# Calculate frequency of each urbanization class
freq_2020 <- terra::freq(degurba[["2020-12-31"]])
print(freq_2020)
} # }