Low Elevation Coastal Zone (LECZ) Global Delta Urban-Rural Population and Land Area Estimates, Version 1

The Low Elevation Coastal Zone (LECZ) Global Delta Urban-Rural Population and Land Area Estimates, Version 1 data set provides country-level estimates of urban, quasi-urban, rural, and total population (count), land area (square kilometers), and built-up areas in river delta- and non-delta contexts for 246 statistical areas (countries and other UN-recognized territories) for the years 1990, 2000, 2014 and 2015. The population estimates are disaggregated such that compounding risk factors including elevation, settlement patterns, and delta zones can be cross-examined. The Intergovernmental Panel on Climate Change (IPCC) recently concluded that without significant adaptation and mitigation action, risk to coastal commUnities will increase at least one order of magnitude by 2100, placing people, property, and environmental resources at greater risk. Greater-risk zones were then generated: 1) the global extent of two low-elevation zones contiguous to the coast, one bounded by an upper elevation of 10m (LECZ10), and one by an upper elevation of 5m (LECZ05); 2) the extent of the world's major deltas; 3) the distribution of people and built-up area around the world; 4) the extents of urban centers around the world. The data are layered spatially, along with political and land/water boundaries, allowing the densities and quantities of population and built-up area, as well as levels of urbanization (defined as the share of population living in "urban centers") to be estimated for any country or region, both inside and outside the LECZs and deltas, and at two points in time (1990 and 2015). In using such estimates of populations living in 5m and 10m LECZs and outside of LECZs, policymakers can make informed decisions based on perceived exposure and vulnerability to potential damages from sea level rise.

《低海拔沿海地带（LECZ）全球Delta城市-农村人口与土地面积估计，版本1》数据集提供了1990年、2000年、2014年和2015年246个统计区域（包括国家和联合国认可的其他地区）的城市、准城市、农村以及总人口（计数）、土地面积（平方公里）和建成区在河流三角洲和非三角洲环境中的估算。人口估算进行了细分，以便可以交叉检验包括海拔、居住模式和三角洲区域在内的复合风险因素。政府间气候变化专门委员会（IPCC）最近得出结论，如果不采取重大的适应和缓解措施，到2100年，沿海社区的风险至少将增加一个数量级，将人员、财产和环境资源置于更大的风险之中。随后生成了高风险区域：1）与海岸相连的两个低海拔区域的全貌，一个以10米为上限（LECZ10），另一个以5米为上限（LECZ05）；2）世界上主要三角洲的面积；3）全球人口和建成区的分布；4）全球城市中心的地域范围。数据在空间上分层，包括政治和陆地/水域边界，允许估计任何国家或地区的人口密度和数量、建成区，以及城市化水平（定义为居住在“城市中心”的人口比例），无论是在LECZs和三角洲内部还是外部，以及在两个时间点（1990年和2015年）。在利用居住在5米和10米LECZs以及LECZs之外的人口估算时，政策制定者可以根据感知到的海平面上升潜在损害的暴露和脆弱性，做出明智的决策。