**6. Conclusions**

The rapid development of satellite-based LiDAR earth observation technology provides an effective way to rapidly collect global surface 3D point clouds, and the advantages and characteristics of laser point cloud data make it a core data component for the construction of the next-generation global mapping database, establishing an infrastructure for the construction of high-precision global control grids and highly efficient surveying of digital elevation maps, and providing support for the rapid construction of high-precision 3D digital geospatial frameworks. At the same time for the global laser point cloud application needs and overall design, it is also necessary to strengthen the research to continuously optimize the technical process, focusing on the following aspects:


Since the first satellite-based laser altimetry satellite ICESat-1 was successfully launched in 2003, after nearly two decades of development, satellite LiDAR earth observation technology has achieved great progress and gradually developed into an emerging remote sensing exploration instrument. Especially since 2018, ICESat-2 satellite (2018), GEDI (2018), Gaofen-7 (2019), Gaofen-14 (2020), and terrestrial ecological environment monitoring carbon satellite (2022) have been continuously

launched into the sky, and the satellite laser observation technology has come to a climax of development. The update of acquiring tools has provided new opportunities for the global mapping technology, and studies have shown that spaceborne laser observation data have strong application potential in the fields of precise positioning of global earth, polar ice sheet monitoring, and shallow ocean topography mapping, etc. It is foreseen that in the near future, with the further development of satellitebased LiDAR technology, it will become possible to directly acquire global digital surface models and digital elevation models, thus providing an active technical way to establish uniformly accurate elevation data in a global even grid, and a new means to establish a higher precision 3D digital earth model.
