GPWv3 depicts the distribution of human population across the
globe. GPWv3 provides globally consistent and spatially explicit
human population information and data for use in research,
policy making, and communications. This is a gridded, or raster,
data product that renders global population data at the scale
and extent required to demonstrate the spatial relationship of
human populations and the environment across the globe.The
purpose of GPW is to provide a spatially disaggregated
population layer that is compatible with data sets from social,
economic, and Earth science fields.The gridded data set is
constructed from national or subnational input units (usually
administrative units) of varying resolutions. The native grid
cell resolution is 2.5 arc-minutes, or ~5km at the equator,
although aggregates at coarser resolutions are also provided.
Separate grids are available for population count and density
per grid cell. Population data estimates are provided for 1990,
1995, and 2000, and projected (in 2004,