West Africa Coastal Vulnerability Mapping: Population Projections, 2030 and 2050

The West Africa Coastal Vulnerability Mapping: Population Projections, 2030 and 2050 data set is based on an unreleased working version of the Gridded Population of the World (GPW), Version 4, year 2010 population count raster but at a coarser 5 arc-minute resolution. Bryan Jones of Baruch College produced country-level projections based on the Shared Socioeconomic Pathway 4 (SSP4). SSP4 reflects a divided world where cities that have relatively high standards of living, are attractive to internal and international migrants. In low income countries, rapidly growing rural populations live on shrinking areas of arable land due to both high population pressure and expansion of large-scale mechanized farming by international agricultural firms. This pressure induces large migration flow to the cities, contributing to fast urbanization, although urban areas do not provide many opportunities for the poor and there is a massive expansion of slums and squatter settlements. This scenario may not be the most likely for the West Africa region, but it has internal coherence and is at least plausible.

西非海岸脆弱性制图：2030年与2050年人口预测数据集，其数据基础为尚未发布的世界栅格人口（Gridded Population of the World, GPW）第四版2010年人口计数栅格数据，但采用了更低的5弧分分辨率。巴鲁克学院的布莱恩·琼斯（Bryan Jones）基于共享社会经济路径4（Shared Socioeconomic Pathway 4, SSP4）生成了国家级人口预测结果。SSP4描绘了一个分化的世界：生活水平相对较高的城市对国内与国际移民具有吸引力。在低收入国家，由于人口压力过高以及国际农业企业大规模机械化农业的扩张，农村人口快速增长的同时可耕地面积却不断缩减。这种人口压力催生了大规模的城市移民潮，推动了快速城市化进程；然而城市区域并未为贫困人口提供充足的发展机会，致使贫民窟与违章聚居区大规模扩张。尽管该情景未必是西非地区最有可能出现的发展路径，但其逻辑自洽且具备起码的合理性。