As an integral part of China's Second Comprehensive Scientific Expedition to the Qinghai-Tibet Plateau and the scientific demonstration plan for a civilian P-band Synthetic Aperture Radar (SAR) satellite, the Institute of Tibetan Plateau Research, Chinese Academy of Sciences (ITPCAS), the Aerospace Information Research Institute (AIR), Chinese Academy of Sciences, the Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, the Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, and Wuhan University recently organized a joint aerial and ground scientific experiment for glacier sounding in the Bayi Glacier area, Haibei Tibetan Autonomous Prefecture, Qinghai Province. This marks the first international attempt to conduct joint P/L/VHF (P-band, L-band, and Very High Frequency) radar glacier sounding experiments based on an aerial platform.
The experiment commenced on March 20 and is expected to conclude by mid-May. To date, 11 sorties have been completed, including 7 sorties for P/L-band tomography and interferometric imaging and 4 sorties for VHF-band perspective imaging, yielding 4.6TB of valid data. Concurrent aerial observations of the ice surface using visible light and LiDAR, as well as airborne instrument calibration on the ice surface, ground-penetrating radar measurements of glacier thickness, and ultra-long-range 3D laser point cloud imaging, have also been carried out.
Preliminary analysis of the acquired data indicates that the 3D reconstruction results from P-band and L-band SAR reflect the changing trends in glacier surface elevation, largely consistent with those from aerial 3D LiDAR and ground surveys. The VHF data provide a clear profile of the glacier, revealing the interfaces between the ice surface and the atmosphere, as well as between the glacier and the bedrock. It also identifies an artificially placed electrically anomalous body at a depth of 80 meters within an ice core drill hole, with the interpreted depth of the profile largely matching ground survey results. These preliminary findings suggest that the experiment has successfully validated comprehensive observation techniques for glacier characteristics and acquired valid data, while also demonstrating the feasibility of the joint P/L/VHF band experiment. In the future, the data obtained from this experiment will be further openly shared through the National Tibetan Plateau Data Center to promote the development of remote sensing inversion methods for glacier thickness and internal structure.
This experiment is of great significance for addressing the challenges of remote sensing monitoring of glacier thickness,breaking through the bottleneck in ice reserve estimation,and leading the next generation of cryospheric remote sensing technology. The development of relevant detection technologies will lay a solid foundation for the conduct of relevant scientific experiments and the development of technologies both domestically and internationally.
During the experiment, experts such as Academician Wu Yirong, President of AIR and a member of the Chinese Academy of Sciences, and Academician Gong Jianya, a professor at the School of Remote Sensing and Information Engineering, Wuhan University and a member of the Chinese Academy of Sciences, visited the Bayi Glacier experiment site for on-site inspections. Wu Yirong emphasized the profound importance of the Chinese Aeronautic Remote Sensing System has acquired the world's first set of effective multi-source remote sensing detection data for mountain glaciers in advancing technological development in China's aerial remote sensing and Earth observation through perspective. The VHF-band airborne radar carried in this flight is the first domestic aerial glacier sounding payload independently developed by AIR and also marks the first flight experiment conducted by the domestically produced MA60 remote sensing aircraft at an altitude exceeding 4,500 meters. He stressed that scientific questions and technological innovations are closely intertwined, and technological progress must be driven by scientific questions while technological innovations should lead to new scientific discoveries.
Gong Jianya highly commended the performance of the Chinese Aeronautic Remote Sensing System has acquired the world's first set of effective multi-source remote sensing detectiondata for mountain glaciers, noting that the collaborative use of P/L-band and VHF multi-source data for detecting internal glacier characteristics is a highly meaningful endeavor with encouraging preliminary results. He pointed out that China currently lacks aerial and satellite technologies capable of directly observing the interior of glaciers, making this experiment of profound significance for promoting the development of China's glacier detection technology and global change research, while also providing important references for the scientific demonstration of China's civilian P-band SAR satellite.
As a national major scienceandtechnology infrastructure, the Chinese Aeronautic Remote Sensing System was officially put into operation in July 2021. It is currently the most comprehensive aerial remote sensing and scientific experiment platform in China, capable of conducting all-weather, high-precision Earth observations. In recent years, it has undertaken numerous large-scale aerial remote sensing comprehensive scientific experiments, new remote sensing payload calibration flights, disaster and environmental monitoring flights, and other scientific research tasks, yielding a batch of valuable scientific data and increasingly prominent social and economic benefits.
The MA60 remote sensing aircraft is parked at Dunhuang Airport
Visible Light DOM (Digital Orthophoto Map) Image of Bayi Glacier
The research team used ground-penetrating radar to survey the thickness of the glacier
