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Global Roads Inventory Project - GRIP - version 4

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Global Road Density Rasters:

Unit: meters per km2 per cell
Cellsize: 5 arcminutes / 0.083333333 degrees
Spatial reference: WGS84, lat lon, degrees

Files:
GRIP4_TOTAL_DENS_m_km2.asc	: density for all roads, equally weighted
GRIP4_TP1_DENS_m_km2.asc	: density for GRIP type 1 - highways
GRIP4_TP2_DENS_m_km2.asc	: density for GRIP type 2 - primary roads
GRIP4_TP3_DENS_m_km2.asc	: density for GRIP type 3 - secondary roads
GRIP4_TP4_DENS_m_km2.asc	: density for GRIP type 4 - tertiary roads
GRIP4_TP5_DENS_m_km2.asc	: density for GRIP type 5 - local roads
GRIP4_area_land_km2.asc		: km2 land area per 5 arcminute cell
GRIP4_density_m_km2.lyr		: ArcGIS lyr-file example density classification

Reference:

Meijer et al 2018 Environ. Res. Lett. https://doi.org/10.1088/1748-9326/aabd42

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