粤港澳大湾区夜间灯光分布及变化图

对影像数据进行几何校正、拼接、投影变换、裁剪等处理，得到大湾区灯光数据和遥感影像。选取一个建成区比较集中且稳定向外扩张的城市，利用1992年Landsat5TM数据提取该城市建成区面积作为参考依据，然后利用1992年年平均夜间灯光数据提取该城市建成区范围：统计不同阈值下（DN值≥n）的该城市建成区面积，直到与遥感影像提取面积最接近为止，利用确定的阈值对整个大湾区夜间灯光数据进行精处理，得到能准确反映城市范围的灯光数据。同理对1998年、2003年、2008年和2013年年平均灯光数据进行处理，最终得到五个不同时期下的城市实际夜间灯光分布数据。这五期数据作为大湾区城市化发展变化的基础数据；利用2015年灯光数据提取大湾区城市建成区范围后，将数据分辨率重采样到810m，作为大湾区城市夜间灯光变化图中的第六张小图，而450m的数据则作为2015年现状图展示出来。

Geometric correction, mosaic, projection transformation, clipping and other processing operations are performed on the image data to obtain the nighttime light data and remote sensing images of the Guangdong-Hong Kong-Macao Greater Bay Area (GBA). A city with concentrated built-up areas that stably expands outward is selected as the reference sample. The 1992 Landsat 5 TM data is used to extract the built-up area of this city as the reference benchmark. Then, the 1992 annual average nighttime light data is utilized to extract the built-up area scope of this sample city: calculate the built-up area of the city under different thresholds (Digital Number (DN) ≥ n) until the extracted area is closest to that derived from remote sensing images. The determined optimal threshold is applied to conduct fine processing on the entire GBA nighttime light data, to obtain light data that accurately reflects the urban built-up scope. The same calibration and processing workflow is applied to the annual average nighttime light data of 1998, 2003, 2008 and 2013, ultimately acquiring five sets of actual nighttime light distribution data of the GBA across five distinct periods. These five datasets serve as the fundamental data for investigating urbanization development and changes in the GBA. After extracting the built-up area scope of the GBA using the 2015 nighttime light data, the data is resampled to a resolution of 810m, which is used as the sixth small sub-figure in the GBA urban nighttime light change map. Meanwhile, the 450m resolution data is presented as the 2015 current status map of the GBA.

搜集汇总

背景与挑战

背景概述

该数据集提供了粤港澳大湾区1992年至2015年六个时期的夜间灯光分布数据，通过处理夜间灯光影像来提取城市建成区范围，旨在反映区域城市化发展变化。数据属于海洋地质学学科，空间覆盖粤港澳大湾区，主要用于研究城市扩张和灯光变化趋势，数据量约为10.41 MB。