Code : 2021066
Event Name : What Can A Land Surveyor Contribute to Weather Observation and Monitoring in the Context of Global Climate Change?
CPD Code : Formal Events
Speaker : Professor LIU Zhi-zhao, George
Associate Head (Partnership), LSGI, PolyU

Dr. George Zhizhao Liu currently is a professor at the Department of Land Surveying and Geo-Informatics, The Hong Kong Polytechnic University (PolyU), Hong Kong. His research Lab, the Micro-Laboratory of Atmospheric Research and Geomatics Engineering (Micro-LARGE), has been focusing on new algorithm development for precise global positioning system (GPS) and global navigation satellite system (GNSS), GPS/GNSS precise point positioning (PPP), ionosphere modeling and scintillation monitoring, atmospheric water vapor remote sensing and modeling, and GPS/GNSS meteorology. He has published more than 100 peer-reviewed papers including 83 journal papers. The average impact factor of his SCI journal papers is 3.342.

Dr. Liu was a recipient of the inaugural Early Career Award of the Hong Kong Research Grants Council (RGC), Hong Kong, in 2012, and the inaugural Best Conference Paper of the China Satellite Navigation Conference (CSNC), China, in 2013. In 2014, he was nominated by the Hong Kong Observatory for the World Meteorological Organization (WMO) Norbert Gerbier-MUMM International Award for 2015 for his article that has developed a method to evaluate the absolute accuracy of water vapor measurements, in addition to numerous other awards and honors. Under his supervision, his PhD students have won numerous awards from PolyU, Hong Kong locally and internationally.

Dr. Liu earned his B.Sc. degree in surveying engineering from the Jiangxi University of Science and Technology, Ganzhou, China, in 1994; his M.Sc. degree in geodesy from Wuhan University, Wuhan, China, in 1997, and his Ph.D. degree in geomatics engineering from the University of Calgary, Calgary, Alberta, Canada, in 2004. He joined the PolyU in 2009 after working for a few years in the GNSS industry in Canada. He served as the President of the International Association of Chinese Professionals in Global Positioning Systems (CPGPS) in 2013. He is a Fellow of the Hong Kong Institution of Engineering Surveyors and the Hong Kong Meteorological Society. Currently he serves in the Editorial Board for three top GNSS journals, as a reviewer for 40+ journals and several national research fund foundations including Australia, Canada, China, and EU.
Event Date : 2021-04-29
Event Time : 7:00 pm - 8:30 pm
Registration Closing Date : 2021-04-28
CPD Hour(s) : 1.5
Divisional PQSL Hour(s) : 1.5
Venue : By online media – ZOOM
Division : LSD
Organizer : Land Surveying Division
Fee : HK$ 150 for members; HK$ 180 for non-members
Priority : First-come-first-served
Language : English
Details :

GNSS is not only a precise positioning and measurement tool for the daily work of a land surveyor, but also a very powerful tool for Earth Observation including the daily weather observation. The occurrence of extreme weather events is becoming increasingly frequent in the context of global climate change. Reliable observation and monitoring of the extreme weather events is essential in the mitigation of those weather-caused disasters. Land Surveyors, using their GNSS technique, actually can play a significant role in the weather observation and monitoring.


Atmospheric water vapor, a greenhouse gas more abundant than the CO2, has a significant impact not only on positioning precision of GNSS application but also on various weather phenomena. In this talk, Dr. Liu will introduce the work centering on atmospheric water vapor observation and modeling, a main research area that his research Lab, the Micro-Laboratory of Atmospheric Research and Geomatics Engineering (Micro-LARGE), has been focusing on over the past decade. His Micro-LARGE Lab observed atmospheric water vapor from GNSS observation data and built the 3D water vapor model for Hong Kong region. Using GNSS observations in Hong Kong, the Micro-LARGE Lab for the first time numerically characterized the spatial and temporal variations of atmospheric water vapor during the life cycle of super typhoons. His Lab developed a novel algorithm that can enhance by nearly 50% the accuracy of global water vapor observation from remote sensing satellites, using GNSS data from the North American GNSS network. At the end of his talk, Dr. Liu will talk about the latest progress on multi-source water vapor data assimilation in Numerical Weather Prediction (NWP) undertaken at the Micro-LARGE Lab in collaboration with scientists at the Hong Kong Observatory.

Remarks :

The event will be conducted online via ZOOM. Successful registrants will be notified separately via email with the web link in due course to the online event .

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Payment : HKD 150