High-resolution high-accuracy orthophoto map and digital surface model of Forni Glacier tongue (Central Italian Alps) from UAV photogrammetry

Abstract

ABSTRACT This work presents the high-resolution high-accuracy orthophoto map and the Digital Surface Model of Forni Glacier (Italian Alps). These represent the status of the glacier tongue in mid-August 2022 when surveys were carried out with a DJI Phantom 4 RTK drone. The processing was carried out in Leica Infinity, and a 3 cm orthomosaic and a 20 cm Digital Surface Model were generated and made available for analysis of the current status of the glacier, which shows signs of downwasting, with the occurrence of collapsing areas and a rapidly changing proglacial landscape. This work can also be used as a reference to investigate the glacier evolution, also in light of climate change. Accuracy requirements of the deliverables were ensured by combining Post Processed Kinematic and Structure from Motion integrated with bundle block adjustment, and using Ground Control Points and Check Points, to guarantee redundancy and evaluate the geolocation accuracy and precision.