Dear GIS-Idea 2026 Conference Secretariat, Thank you very much for accepting our paper entitled: “Spatio-Temporal Deep Learning for Drifting Buoy Trajectory Forecasting: Multi-Dataset Evaluation and Operational Error Characterization” We regret to inform you that, due to unforeseen circumstances, we will not be able to present this paper at the GIS-Idea 2026 Conference as scheduled. We sincerely apologize for any inconvenience this may cause and greatly appreciate your understanding and consideration. We are grateful to the Organizing Committee for the opportunity to participate in the conference and hope to have the opportunity to contribute to future GIS-Idea events.

Best regards,

------------------------------------------------------------------------------------------------ PGS.TS Nguyễn Gia Trọng Trưởng Bộ môn Trắc địa cao cấp Khoa Trắc địa - Bản đồ và Quản lý đất đai, Trường Đại học Mỏ - Địa chất Trưởng nhóm nghiên cứu Trắc địa cao cấp - môi trường Điện thoại: (+84) 963124980 Email: nguyengiatrong@humg.edu.vn

Assoc. Prof. Dr. Nguyen Gia Trong Head of Department of Geodesy Faculty of Geomatics and Land Administration, Hanoi University of Mining and Geology Head of Geodesy and Environment Research Group Phone: (+84) 963 124 980 Email: nguyengiatrong@humg.edu.vn