News

RILS co-organised The Third ACOWS Workshop at PolyU

The third Workshop on Atmospheric and Coastal Observations for Weather Servicing (ACOWS 2024) was hosted by Prof. George LIU, Professor at the Department of Land Surveying & Geo-Informatics (LSGI) and member of Research Institute for Land and Space (RILS), at The Hong Kong Polytechnic University (PolyU) during 2-3 April 2025. This year’s theme, “Data Assimilation for a Better Weather Forecasting”, brought together experts to explore cutting-edge advancements in weather prediction methodologies. Renowned scientists from Mainland China were invited to attend this Workshop and present their work. They are Prof. Jianhua SUN from the Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing; Prof. Yaodeng CHEN from the School of Atmospheric Sciences, Nanjing University of Information Science and Technology; Dr Yerong FENG, Director, from the Guangdong–Hong Kong–Macao Greater Bay Area Weather Research Centre for Monitoring Warning and Forecasting, Shenzhen; Dr Yuanfu XIE, Chief Scientist, from the Guangdong–Hong Kong–Macao Greater Bay Area Weather Research Center for Monitoring Warning and Forecasting, Shenzhen; Prof. Donghai WANG from the School of Atmospheric Sciences, Sun Yat-sen University; and Dr Chunqing SHANG, the Huawei Technologies Company.   Presentations focused on innovative approaches to “Forecasting of Heavy Rainfall using multi-source PWV data assimilation and ensemble prediction”, a work package being led by Prof LIU. Discussions highlighted the integration of multi-source data to enhance predictive accuracy and address climate resilience challenges. The Workshop fostered interdisciplinary collaboration, bridging academic research with operational weather servicing needs.

RILS research reveals sharp depletion in soil moisture, driving land water to flow into the oceans and contributing to a rise in sea levels

The increasing frequency of once-in-a-decade agricultural and ecological drought has underscored the urgency of studying hydrological changes. A research team from the Department of Land Surveying and Geo-informatics of The Hong Kong Polytechnic University (PolyU) has collaborated with international experts to analyse the estimated changes in land water storage over the past 40 years by utilising space geodetic observation technology and global hydrological change data. This innovative method has revealeda rapid depletion in global soil moisture, resulting in a significant amount of water flowing into the oceans, leading to a rise in sea levels. The research provides new insights into the driving factors behind the alarming reduction in terrestrial water storage and rise in sea levels. The findings have been published in the international journal Science. Since polar motion reflects mass redistribution within the Earth system, integrating models and observations across the atmosphere, hydrosphere and lithosphere is crucial. However, previous challenges in measuring terrestrial water storage, particularly groundwater and root zone soil moisture, limited understanding of hydrological depletion at continental scales. Prof. Jianli CHEN, Professor of the PolyU Department of Land Surveying and Geo-informaticsand core member of the Research Institute for Land and Space and the international team employed satellite altimetry and gravity missions, including the Gravity Recovery and Satellite Experiment (GRACE), and GRACE Follow-On, to enable continental-scale observations of terrestrial water storage variations. By integrating this with global mean sea levels and polar motion data, the team has explored terrestrial water storage depletion patterns. Notably, this study introduced novel methods for estimating global soil moisture, which improves the accuracy of continental and global scale modeling to enable a more effective understanding of soil moisture variations under climate change. The melting of Greenland’s ice sheet is recognised as the largest single contributor to the rise in global sea levels, adding approximately 0.8mm annually. This study reveals that between 2000 and 2002, the global terrestrial water storage significantly declined, with a total of 1,614 billion tons of water lost to the oceans, which is twice as much as resulting from the current melting of Greenland ice, and equivalent to a 4.5mm rise in sea levels. Since then, the rapid loss of terrestrial water storage has been followed by a more gradual but continuous depletion, with no signs of recovery. In addition, compared to the period from 1979 to 1999, a notable decline in global average soil moisture was observed from 2003 to 2021. Between 2003 and 2011, the Earth’s pole shifted 58cm toward 93° East Longitude, demonstrating that the continued decline in soil moisture is leading to a reduction in terrestrial water storage. The team also pointed out that precipitation deficits and stable evapotranspiration caused by global warming, changing rainfall patterns and increasing ocean temperaturesare likely the key factors for the abrupt decline in terrestrial water storage. The ERA5-Land soil moisture data of the European Centre for Medium-Range Weather Forecasts’ corroborates these findings, showing substantial terrestrial water storage losses in Africa, Asia, Europe, and South America. In Asia and Europe, the affected areas expanded from northeastern Asia and eastern Europe to broader regions across East and Central Asia, as well as Central Europe, following the sharp water storage depletion observed between 2000 and 2002. With increasing agricultural irrigation in regionssuch as northeast China and the western United States, and global greening, soil moisture may further diminish in semi-arid areas with intensive agriculture and high levels of greening. The team suggests the need for improved land surface models which consider these factors for a more comprehensive understanding of long- term changes in terrestrial water storage. Prof. Jianli CHEN said, “Sea level change and Earth rotation serve as indicatorsof large-scale mass changes in the Earth system. Accurately measured sea level change and variation in Earth rotation provide a unique tool for monitoring large-scale mass changes in the global water cycle. By integrating multiple modern space geodetic observations, it enables comprehensive analysis of the driving factors behind changes in terrestrial water storage and sea level rise. This, in turn, provides reliable data for climate and Earth system science experts to further investigate drought issues, aiding authorities in formulating water resource management and climate change mitigation strategies to address new challenges posed by climate change.”

RILS co-organises workshop on sustainable urban development and ecological conservation

The Hong Kong Polytechnic University (PolyU) and China Innovative Urban-Rural Governance Research Network (CIURG) co-hosted a workshop under the theme of Sustainable Urban Development and Ecological Conservation on 2 April 2025.  The workshop took place in the Mai Po Nature Reserve, a wetland listed as a “Ramsar site” for its international importance. Located in Yuen Long, the Mai Po Nature Reserve is hailed as paradise for migratory birds, providing diverse habitats such as gei wai, mangroves, intertidal mudflats, reedbeds and many more to local wildlife species including waterbirds, aquatic fauna and insects.  The sanctuary is facing ecological challenges as the Northern Metropolis project includes filling fish ponds and removing woodland in the Reserve to construct part of the San Tin Technopole, a new hub for clustered innovation and technology development. Against this background, the workshop brought together 31 leaders and representatives across different sectors and institutions, including universities, government bodies and non-governmental organisations, to explore actionable strategies for nature conservation for sustainable development.  The activity was co-organised by several PolyU units, including the Research Institute for Land and Space (RILS), the Research Centre for Nature-based Urban Infrastructure Solutions (RNUS), the Research Institute for Sustainable Urban Development (RISUD), and the Department of Civil and Environmental Engineering (CEE), together with CIURG. It included technical sessions and guided tour around the Reserve.  The technical sessions, chaired by Prof. DING Xiaoli, Director of RILS, and Prof. WANG Yuhong, Director of RNUS, covered multiple topics related to the workshop theme.  These included: the Northern Metropolis development plan; digital tourism; the plan, development, and protection of Hengshui Lake National Nature Reserve; sustainable blue economy; wildlife and plants conservation; and nature-based solutions in urban design. Other guest speakers included: Ms LEUNG Kar Yee, Carrie, Chief Engineer of North Development Office at the Civil Engineering and Development Department, HKSAR; Mr SU Wansheng, Chief Executive Officer of Fujian Ticket Payment Information Technology Co., Ltd.; Mr LIU Guangning, Director of Hengshui Lake National Nature Reserve; Ms Martin KATE, Consultant at Financing Marine Conservation; Ms. Camilla ZANZANAINI, Founder and Chief Executive Officer of Nature Makers Lab; Mr David STANTON, Executive Director of Ecology and Biodiversity-Hong Kong, Aurecon; Prof. CHEN Hongyue, Professor of South China Agricultural University; Prof. LUO Chunling, Professor of Guangzhou Institute of Geochemistry, Chinese Academy of Sciences; Prof. DENG Xiaomei, Associate Professor at Tsinghua University; Dr. NAZEER Majid, Research Assistant Professor at PolyU; Prof. HUANG Shuping, Associate Professor at Fujian University of Technology.  Participants had fruitful discussions and were guided through various natural habitats during the tour, enjoying an immersive experience in nature and rethinking the human-nature relationship. This workshop is funded by the Public Policy Research Funding Scheme of the Chief Executive’s Policy Unit, HKSAR.  RILS would like to thank all parties including participants, the World Wildlife Fund Hong Kong (WWF HK) and sponsor, for supporting this meaningful event.  

RILS cohosts thematic seminar on hydrographic survey

The Research Institute for Land and Space (RILS) of The Hong Kong Polytechnic University (PolyU), together with the Hong Kong Institute of Surveyors (HKIS) and the Royal Institution of Chartered Surveyors (RICS), under the support of the Civil Engineering and Development Department (CEDD), has previously launched “The New Era of Hydrographic Survey”, a dedicated event series aimed at providing engineering professionals across universities, government bodies and industry with comprehensive insights into the latest advancements in the hydrographic surveying technology of CEDD, particularly the new survey vessel “Port Works 5” (PW5) of the department.   The second event of the series, a Joint Continuing Professional Development (CPD) Seminar on the theme, was successfully held on 26 March 2025, and was attended by over 100 participants.   Prof. DING Xiaoli, Director of RILS, opened by seminar by extending a warm welcome to all participants and highlighting the growing importance of hydrographic surveying in marine infrastructure development and climate resilience as well as the critical role of interdisciplinary collaboration and innovation in advancing geospatial science.   The seminar featured presentations by representatives from several HKSAR government departments.  Speakers included: Sr CHEUK Yuet Wai, Tim, Assistant Hydrographer of the Marine Department; Sr CHENG Tsz-yan, Tess, Land Surveyor of the Lands Department; and Sr LEUNG Ching-hung, Cherry, Land Surveyor of CEDD.  Their sharing covered multiple areas related to PW5 and hydrographic survey services, including the design features that enable the vessel to operate in diverse marine environments and support a wide range of survey missions, the challenges faced during the construction of PW5, and the need for adaptability, innovation and continuous professional development in the field to meet evolving engineering and surveying industry demands.   A panel discussion, moderated by Dr KWAN Shun-hang, Julian, Assistant Director (Technical) of CEDD, followed, spurring conversation among participants on the challenges and opportunities in hydrographic survey.  All members had a fruitful exchange of views, acknowledging the importance of capacity-building in the field through cross-sectoral knowledge sharing and collaboration, thus contributing professional expertise to Hong Kong’s smart and sustainable city development.

Associate Director of RILS shares research on floating solutions at Consul General Talk

The 6th Consul General Talk organised by the Policy Research Centre for Innovation and Technology (PReCIT) and supported by the Faculty of Applied Social Sciences, Global Engagement Office and Research Institute for Land and Space (RILS) of PolyU, successfully concluded on 25 March 2025 on campus. The talk featured Mr Maurits TER KUILE, Consul General of the Kingdom of the Netherlands to Hong Kong and Macau, who shared his experiences and insights in Dutch diplomacy. The Netherlands is a pioneer in developing floating solutions, presenting an exemplary model of new generation water-based architecture and public space. Taking this opportunity, Prof. Xiao Lin ZHAO, Associate Director of RILS, presented some examples of floating structures in the Netherlands, the vision of floating cities and research at RILS in this exciting field.

RILS co-organises workshop on nature-based rural dual circular economy

The Hong Kong Polytechnic University (PolyU) and China Innovative Urban-Rural Governance Research Network (CIURG) co-hosted a workshop under the theme of Nature-based Urban-Rural Dual Circular Economy on 10 March 2025.  Co-organised by several PolyU units including the Research Institute for Land and Space (RILS), the Research Centre for Nature-based Urban Infrastructure Solutions (RNUS) and the Research Institute for Sustainable Urban Development (RISUD), together with CIURG, the workshop brought together more than 50 leaders and representatives from diverse sectors, including universities, government bodies, non-government organisations and rural communities, to explore actionable strategies for promoting an urban-rural circular economy. Prof. LI Xiangdong, Dean of the Faculty of Construction and Environment, Director of RISUD, opened the workshop by emphasising the importance of a nature-based approach (NbS) in achieving sustainable and balanced urban and rural development.  The workshop included three engaging sessions that delved into topics including sustainable resource management, waste reduction, innovative land use policies, cultural heritage preservation, community empowerment, integrated urban-rural planning, and the role of technology in advancing environmental and economical practices. The sessions, each had a different sub-theme, were chaired by Prof. Ivy WONG Siu Wai, Convener of CIURG, Prof. WANG Yuhong, Director of RNUS, and Prof. DING Xiaoli, Director of RILS.  A distinguished line-up of speakers shared their insights and presentations on various topics. Featured guest speakers included: Prof. LING Kar-kan, Director of Jockey Club Design Institute for Social Innovation at PolyU; Ms XING Wenwei, Olivia, Founder of Hong Kong Urban-Rural Sustainable Development Association; Prof. TANG Man Bun, Stephen, Head of Countryside Conservation Office at the Environment and Ecology Bureau of the Hong Kong SAR Government; Ms LEUNG Kar Yee, Carrie, Chief Engineer of North Development Office at the Civil Engineering and Development Department of the Hong Kong SAR Government; Ms Kitty TAM, Programme Lead of Hong Kong 2025 from Civic Exchange; Prof. WONG Kam-sing, Former Secretary for the Environment of the Hong Kong SAR Government, and Chairman of Wu Zhi Qiao (Bridge to China) Charitable Foundation; Mr HE Yunhui, village leader from mainland China; and PolyU scholars including Prof. Ding, Prof. Ivy WONG Siu Wai, Prof. WANG Yuhong, Prof. LEU Shao-Yuan, Prof. Charles WONG Man Sing and Prof. DUAN Huan-Feng. The workshop encouraged cross-sectoral dialogues about NbS.  It also provided an important platform for exploring the potential application of NbS in the development of the Northern Metropolis and for fostering sustainable urban-rural development, and gaining a deeper understanding into the rural communities’ perspectives and needs. RILS would like to thank all participants for their valuable contributions to the workshop, and K. Wah Construction Materials Limited for inviting village leaders and representatives from the Northern Metropolis to join and enrich the discussions with their important views.

RILS delegation visits CEDD’s new survey vessel “Port Works 5” (PW5)

A delegation from the Research Institute for Land and Space (RILS), led by Sr Prof. Ben CHAN, Professor of RILS and Prof. George LIU, RILS Core Member and Associate Head (Partnership) of the Department of Land Surveying and Geo-Informatics (LSGI) visited the new survey vessel “Port Works 5” (PW5) of the Civil Engineering and Development Department (CEDD), HKSAR.   This technical visit, a part of the event series “The New Era of Hydrographic Survey”, was jointly organised by RILS, the Land Surveying Division of the Hong Kong Institute of Surveyors (HKIS) and the Royal Institution of Chartered Surveyors (RICS), with the support of CEDD.  The event series aims to provide participants with comprehensive insights into the latest advancements in hydrographic surveying technology of CEDD.   The visit highlighted the innovative solutions including digital tools and advanced surveying techniques which CEDD adopted to address various challenges in efficiency, environmental sustainability and infrastructure resilience encountered in hydrographic surveying.  It also exemplified the importance of tripartite collaboration between government, professional institutions and academia.  During the visit, participants across the sectors engaged in fruitful discussions on the applications of hydrographic survey technology and the need for enhanced research and improved data accessibility in the field through interdisciplinary and cross-sectoral collaborations. The visit has provided an important platform for fostering cross-sectoral dialogues and networks essential for advancing hydrographic surveying.    Acknowledgment RILS extends the Institute’s gratitude to CEDD for facilitating this visit and providing valuable insights into PW5’s operations and technological advancements.  RILS would also like to thank all invited speakers and fellow participants for their inputs and participation during the visit.

Prof. Huan-feng DUAN honoured with “2024 Dayu Water Conservancy Science and Technology Progress Award”

Congratulations to Prof. DUAN Huan-feng, Member of the Research Institute for Land and Space (RILS) and Professor in the Department of Civil and Environmental Engineering, on receiving the “2024 Dayu Water Conservancy Science and Technology Progress Award (2nd Class)” by the Ministry of Water Resources of China, for his project titled “Key Technologies for Real-time Hydraulic Simulation and Precise Regulation of Complex Urban Water Supply Networks”. This accolade is given to individuals who have made exceptional technological innovations and significant contributions to the advancement of water science and technology, bringing substantial economic and social benefits. Prof. Duan’s research focuses on the critical areas of hydraulics and water resources, including urban hydraulics, urban asset management, coastal urban flooding, hydro-environmental management and computational fluid mechanics. He has spearheaded numerous significant research projects and secured grants from various funding bodies in Hong Kong and the Mainland China.  

RILS & RNUS Joint Public Lecture delivered by Professor Xiangrong WANG was successfully held

On 9 December 2024, Prof. Xiangrong WANG, Director and Distinguished Professor, Centre for Urban Eco-Planning & Design, Fudan University, China, delivered an online Public Lecture titled “Urban Ecological Security and Green Development”. This lecture was co-organised by the Research Institute of Land and Space (RILS) and the Research Centre for Nature-based Urban Infrastructure Solutions (RNUS) of the Hong Kong Polytechnic University.In this lecture, Prof. WANG presented the ecological security assessment of international metropolises, including London, New York, Hong Kong, Shanghai and etc. He analyzed this topic through three key aspects: 1) Origin and connotation: Ecological security of metropolises from a global perspective; 2) Exploration and cognition: Low-carbon development model of international metropolises under climate change; 3) Paths and countermeasures: Paths and countermeasures of urban green development based on nature-based solutions model.The lecture included a fruitful Q&A session, allowing participants to share their insights on the topic. This interactive discussion fostered a rich exchange of ideas, enhancing the collective understanding of urban ecological security and green development.About Prof. Xiangrong WANG:Prof. Xiangrong WANG is currently the director and distinguished professor of the Centre for Urban Eco-Planning & Design of Fudan University in Shanghai China, the director of National Centre for Virtual Simulation of Environmental Science, Fudan University, and the Vice Chairman of Urban Ecological Commission of Ecological Society of China, Chief supervisor of Shanghai Ecological Society. In addition, he is the Chair of Environmental Science and Healthy City Division of Shanghai Municipal Construction Commission, and Counselor of Shanghai Municipal People's Government, the editorial members of some academic journals, such as the editor-in-chief of Journal of World Forestry (Hans Press, USA), vice editor-in-chief of Journal of China’s Urban Forestry, editors of Acta Ecological Sinica, Chinese Journal of Ecology, Chinese Journal of Eco-Agriculture, Journal of Environmental Science & Technology, etc, and reviewers of some International Journals such as Ecological Engineering, Landscape and Urban Planning, and JHM, JCP. etc. He also served as a regional vice-chair of East Asia, the IUCN Commission on Education and Communication during 2004-2012 and a steering member of INTECOL Association.  

RILS scholar was invited to present at the 2024 ASAIHL Conference

At the recent 2024 ASAIHL Conference (Association of Southeast Asian Institutions of Higher Learning) held at the Universitas Airlangga, Surabaya, Indonesia on 19-22 November 2024, Prof. George Zhizhao LIU, member of RILS and Professor of LSGI, was invited to present the Hong Kong (China)’s Region/Country Report at the conference. The theme of this year’s ASAIHL conference is “University’s Role in Advancing Climate Crises Reduction.” At the conference, Prof. LIU gave an invited talk titled “AI and Satellite Remote Sensing: the State-of-the-art Technology to Map the Most Abundant Atmospheric Greenhouse Gas –– Water Vapor”, which illustrated the importance of accurate water vapor observation in the climate change and extreme weather studies and showcased the research work conducted in Prof. LIU’s Micro-Laboratory of Atmospheric Research and Geomatics Engineering (Micro-LARGE) in the field of climate change.   Water vapor, as the largest greenhouse gas in the atmosphere, plays a critically important role in climate change and extreme weather events. This might be against the orthodox opinion that usually believes the carbon dioxide (CO2) is the largest greenhouse gas. Water vapor accounts for approximately 50% atmospheric greenhouse gas, depending on the weather conditions. Nevertheless, the accurate observation of water vapor is still a global technical challenge. A large number of satellites have been launched, and many have the capability to observe water vapor at different wavelength channels. Unfortunately, the water vapor data accuracy of most of these satellite sensors is low and cannot meet the requirement for climate change and extreme weather studies. Prof. LIU’s Micro-LARGE Lab insightfully pinpointed this problem and has developed different AI-based novel algorithms to significantly improve the accuracy of water vapor observations of different satellite sensors.   The Association of Southeast Asian Institutions of Higher Learning (ASAIHL), founded in Bangkok, Thailand in 1956, is a non-governmental organization starting with eight state universities in Southeast Asia but now with university memberships extending to Europe, North America, Africa, and Oceania. ASAIHL’s purpose is to assist member institutions to strengthen themselves through mutual self-help and to achieve international distinction in teaching, research and public service.