School of Remote Sensing and Geomatics Engineering, Nanjing University of Information Science & Technology, Nanjing 210044, China.
State Key Laboratory of Resources and Environmental Information System, Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China.
Sensors (Basel). 2020 Nov 19;20(22):6631. doi: 10.3390/s20226631.
The combination of Landsat-8, Landsat-9, Sentinel-2A and Sentinel-2B data provides a new perspective in remote sensing application for terrestrial monitoring. Jointly, these four sensors together offer global 10-30-m multi-spectral data coverage at a higher temporal revisit frequency. In this study, combinations of four sensors were used to examine the revisit interval by modelled orbit swath information. To investigate different factors that could influence data availability, an analysis was carried out for one year based on daytime surface observations of Landsat-8 and Sentinel-2A -2B. We found that (i) the global median average of revisit intervals for the combination of four sensors was 2.3 days; (ii) the global mean average number of surface observations was 141.4 for the combination of Landsat-8 and Sentinel-2A -2B; (iii) the global mean average cloud-weighted number of observations for the three sensors combined was 81.9. Three different locations were selected to compare with the cloud-weighted number of observations, and the results show an appropriate accuracy. The utility of combining four sensors together and the implication for terrestrial monitoring are discussed.
Landsat-8、Landsat-9、Sentinel-2A 和 Sentinel-2B 数据的组合为陆地监测的遥感应用提供了新视角。这四个传感器联合提供了全球 10-30 米多光谱数据，具有更高的时间重访频率。在这项研究中，使用了四个传感器的组合，通过模拟轨道条带信息来检查重访间隔。为了研究可能影响数据可用性的不同因素，基于 Landsat-8 和 Sentinel-2A-2B 的日间地表观测，对一年的数据进行了分析。结果发现：（i）四个传感器组合的全球中位数平均重访间隔为 2.3 天；（ii）Landsat-8 和 Sentinel-2A-2B 组合的全球平均地表观测次数为 141.4 次；（iii）三传感器组合的全球平均云加权观测次数为 81.9 次。选择了三个不同的地点进行比较，结果显示出了适当的准确性。讨论了四个传感器的组合使用以及对陆地监测的意义。
