The International Association of Geodesy (IAG) is the most authoritative global academic organization in the field of international geodesy. It was established in Berlin, Germany in October 1864 and has a long history of more than 150 years. IAG's most important global event is the IAG science conference held every four years. Recently, the IAG 2021 science conference, sponsored by the international geodetic Association, hosted by the China Society of Surveying and mapping, and co sponsored by 19 well-known universities and scientific research institutes such as the China Academy of Surveying and mapping and the China University of mining and technology, was held in Beijing. 1269 experts and scholars from 50 countries around the world gathered in the "cloud" for comprehensive and in-depth academic exchanges. 25737 people successively participated in the conference through online video live broadcast.

Annette Eicker, chairman of climate change research cross committee of IAG, made a special report on the contribution of geodetic results to climate change research. Academician Yang Yuanxi made a special report entitled "Characteristic service and performance of beidou-3 satellite navigation system". Zhao Dongsheng, a teacher of  CESI, gave a report entitled "Extracting Ionospheric Phase scintillation index from 1 Hz GNSS observations", which introduced the research work of monitoring polar ionospheric scintillation by geodesic receiver. Li Haobo, a doctoral student, gave a report entitled "Estimating a new method for heavy rainfall detection using optimal abnormal based thresholds of predictors derived from gnss-pwv", which introduced the research work of using gnss-pwv analysis results to build a short-term and imminent prediction and early warning model for extreme rainstorm events. Zhang Wenyuan, Shi Jiaqi and Yu Zhangjun, graduate students of the college, respectively gave lectures entitled "Estimation of 4D atmospheric water vapor from GNSS and infrared sensor data: a combined tomography approach", "Spatial temporary characteristics of the turbopause height over global tropical and subtropical region using cosmic-2 Ro data" .