High-spatiotemporal-resolution mapping of global urban change from 1985 to 2015
High-spatiotemporal-resolution mapping of global urban change from 1985 to 2015
复制标题
DOI：
10.1038/s41893-020-0521-x
复制
发表时间：
2020-05-04
影响因子：
27.6
通讯作者：
Zeng, Zhenzhong
中科院分区：
文献类型：
--
作者：
Liu, Xiaoping;Huang, Yinghuai;Zeng, Zhenzhong
高分辨率全球城市土地年度覆盖图提供了全球环境变化的基本信息，并有助于与减缓气候变化和城市规划促进可持续发展有关的应用。在这里，我们绘制全球年度城市动态从1985年到2015年，在30米的分辨率，使用大量的地表反射率数据从陆地卫星。我们发现，全球城市范围每年扩大9，687 km（2）。这一速度是之前对世界各地单个城市的可靠估计的四倍，表明全球城市化的速度前所未有。城市扩张的速度明显快于人口增长的速度，这表明城市土地面积已经超过了维持人口增长所需的水平。展望未来，将这些地图与综合评估模型结合使用，可以促进更好地了解城市化对环境的复杂影响，并帮助城市规划者避免自然灾害;例如，通过限制洪水风险区的新开发。该研究发现，自1985年以来，全球城市土地的扩张速度比以前认识到的要快四倍，而且比人口增长的速度要快。
High-resolution global maps of annual urban land coverage provide fundamental information of global environmental change and contribute to applications related to climate mitigation and urban planning for sustainable development. Here we map global annual urban dynamics from 1985 to 2015 at a 30 m resolution using numerous surface reflectance data from Landsat satellites. We find that global urban extent has expanded by 9,687 km(2) per year. This rate is four times greater than previous reputable estimates from worldwide individual cities, suggesting an unprecedented rate of global urbanization. The rate of urban expansion is notably faster than that of population growth, indicating that the urban land area already exceeds what is needed to sustain population growth. Looking ahead, using these maps in conjunction with integrated assessment models can facilitate greater understanding of the complex environmental impacts of urbanization and help urban planners avoid natural hazards; for example, by limiting new development in flood risk zones.The world keeps urbanizing. This study finds that since 1985 global urban lands have expanded four times faster than previously recognized and faster than population is growing.