Population in Drylands - Total

The concept of drylands continues to be debated. In this data set, drylands are taken as areas with a potential hazard of desertification. The hyperarid zone is not subject to desertification and is therefore excluded. Hence drylands are defined as the arid, semi-arid and dry subhumid zones, or areas with lengths of growing periods of 1-179 days. Global population database from: Tobler, W., U. Deichmann, J. Gottsegen and K. Maloy (1995), The global demography project, Technical Report 95-6, NCGIA, Santa Barbara. The population surface derives from the latest available national census data, which however varied by country from 1979 to 1994. Standard population growth models were used to derive estimates for 1994.