News

Geely Holding Delegation visits PolyU

A delegation from Zhejiang Geely Holding Group Co., Ltd.  (Geely Holding) visited The Hong Kong Polytechnic University (PolyU) on 26 February. Both parties engaged in in-depth discussions on scientific research collaboration and talent cultivation. Prof. DONG Cheng, Associate Vice President (Mainland Research Advancement) of PolyU, introduced the university's outstanding achievements in academic research, technological innovation, and the collaboration between industry, academia, and research. Meanwhile, Mr. REN Xiangfei, Executive Vice President of the Geely Research Institute, provided a comprehensive overview of Geely Group's current development, future strategies, and key technologies driving automotive advancement. During the meeting, Ir Prof. CHAN Ching-chuen, Distinguished Chair Professor of the Department of Electrical and Electronic Engineering of PolyU, Prof. YANG Hongxia, Associate Dean (Global Engagement) of the Faculty of Computer and Mathematical Sciences of PolyU, and Prof. ZHAO Haitao, Professor of the Department of Electrical and Electronic Engineering of PolyU, presented their research on electric vehicle, large language models, and smart manufacturing, showcasing PolyU's leading research in these vital fields. Following the meeting, the delegation visited the Research Centre for Electric Vehicles and explored the university's research facilities and achievements. This visit provided an excellent platform for communications between Geely Holding and PolyU, establishing a solid foundation for future collaborations and contributing to the high-quality development of China’s automotive industry.

PolyU develops real-time system for monitoring atmospheric corrosion on buildings in Hong Kong

Located in a subtropical region facing the South China Sea, during summer Hong Kong experiences high salinity in the warm sea air which corrodes the metal structures of buildings. To address this challenge posed by the humid environment, researchers from the Department of Civil and Environmental Engineering of The Hong Kong Polytechnic University (PolyU) have developed a real-time monitoring system to evaluate the impact of atmospheric corrosion on steel structures and components in buildings. This system has been deployed to monitor the structural corrosion of a newly-built research complex and a housing project. Based on the data collected, targeted protective measures have been proposed to help achieve sustainable building development. Prof. Kwok-fai CHUNG, Professor of the PolyU Department of Civil and Environmental Engineering and Director of the Chinese National Engineering Research Centre for Steel Construction (Hong Kong Branch), along with his team, have been conducting atmospheric exposure tests at seven sites across Hong Kong since 2010. The results indicate that the corrosion rate of carbon steel typically ranges from 30 to 40 µm per year, whereas zinc and galvanised steel used for outdoor construction exhibit corrosion rates of approximately 3 µm per year. The commercial complexes located around Victoria Harbour are particularly vulnerable to year-round atmospheric corrosion, which compromises the durability of buildings and structures and can even pose safety risks. To assist engineers and professionals in formulating more effective building maintenance strategies, Mr Ka Fai YUEN, PhD student from the PolyU Department of Civil and Environmental Engineering has developed a real-time corrosion monitoring system under the supervision of Prof. Kwok-fai Chung. Between 2020 and 2024, Mr Yuen collected approximately 40,000 real-time corrosion and environmental datasets per year from seven different buildings across Hong Kong. Utilising advanced electrochemistry technology integrated with remote sensing and AI-supported data analytics, the system can evaluate the effects of corrosive chemicals such as chlorine ion, sulphur dioxide and nitrogen oxide, as well as collect climatic data including temperature and humidity on steel members and structures. The system significantly improves upon the accuracy of conventional corrosion prediction models and enables long-term corrosion monitoring and assessment for buildings in Hong Kong. Led by Prof. Chung, the Chinese National Engineering Research Centre for Steel Construction (Hong Kong Branch), has been invited by the Hong Kong Construction Industry Council and Hong Kong Council of Social Service (HKCSS) respectively to apply the system for corrosion monitoring in the InnoCell at Hong Kong Science Park and technical monitoring of Nam Cheong 220, a social housing project coordinated by HKCSS, to validate the effectiveness of the system and provide critical data for developing appropriate building maintenance strategies. InnoCell is the first building in Hong Kong to adopt a modular integrated construction (MiC) approach. During the two-year monitoring period, the team assessed the corrosion rates of steel structures and their components in both indoor and outdoor environments. The findings revealed that the corrosion rate of steel in indoor environments is only one-third of that in outdoor environments, demonstrating that atmospheric conditions play a significant role in corrosion assessment. Therefore, different levels of corrosion protection should be implemented for indoor and outdoor steel components, with priority given to protecting external steel components to enhance their durability and lifespan. Nam Cheong 220 is Hong Kong’s first structural steel social housing project to adopt modular integrated construction (MiC) technology. The team’s monitoring results showed that the corrosion condition of this type of building was similar to typical buildings in Hong Kong, with no significant corrosion damage observed. These findings align with the inspection results of the steel components during the building’s deconstruction and relocation process, demonstrating that MiC technology is suitable for repeated use and offers an ideal solution for the reuse and relocation of transitional housing. Prof. Kwok-fai Chung said, “Hong Kong’s unique tropical climate and marine environment make atmospheric corrosion a critical issue for buildings. The results of this study will help develop more effective building maintenance strategies, prolonging the lifespan of buildings and structures with reduced manpower and lower cost, thereby contributing to the sustainable development of society.” Mr Ka Fai Yuen said, “PolyU has provided me with invaluable opportunities to apply my knowledge and research findings in practical ways to address societal challenges. These experiences are essential for my future research and personal development.”

Visit by Shunde District delegation

A delegation from Shunde District visited PolyU on 24 February to engage in industry-academia-research exchanges, aiming to fostering collaboration in research projects, technological innovation and transfer, as well as joint talent development initiatives. Prof. DONG Cheng, Associate Vice President (Mainland Research Advancement) and Chair Professor of Cell Engineering and ImmunoMedicine in the Department of Biomedical Engineering of PolyU warmly welcomed the delegation. He highlighted PolyU's remarkable achievements in research, innovation, and industry-academia collaboration, emphasizing its commitment to transforming research into practical solutions and applications for sustainable societal and economic development. Several PolyU scholars also shared the latest research progress in their respective faculties, and explored potential industrial applications. Prof. Henry DUH, Associate Dean (Global & Industry Engagement) of the School of Design and Director of Research Centre for Art and Culture Technology, explained how artificial intelligence is empowering the cultural and creative industries, driving cross-disciplinary innovation; Prof. LIU Yan, Associate Professor of the Department of Computing, introduced the newly established Faculty of Computer and Mathematical Sciences and shared how artificial intelligence and human-machine interaction technology are being used to analyse and improve personal stress resistance and performance; Prof. Hailong HUANG, Assistant Professor of the Department of Aeronautical and Aviation Engineering, discussed how perception modules and cutting-edge sensor technology contribute to the development of the low-altitude industry and its potential economic applications. Both sides engaged in in-depth discussions on topics such as robotics technology and talent cultivation, expressing interest in collaborative initiatives.  The delegation also visited PolyU's State Key Laboratory of Ultra-precision Machining Technology to explore its cutting-edge scientific research and advanced laboratory facilities. PolyU will continue to leverage its advantages in academic and technological innovation, join forces with the Shunde District to promote the transformation of R&D achievements and talent cultivation, and support the high-quality development of the Guangdong-Hong Kong-Macao Greater Bay Area.  

PolyU student honoured as the first undergraduate from Hong Kong to present outstanding research at the International Microwave Symposium 2025

Under the guidance of Dr ZHOU Xinyu, Research Assistant Professor and Head of the RF Microelectronics Circuit (RFMC) Laboratory in the Department of Electrical and Electronic Engineering at the Hong Kong Polytechnic University (PolyU), Mr BI Jingyun, an undergraduate student in the RF Microelectronics Circuit (RFMC) Laboratory at PolyU, has achieved a significant milestone by being invited to present his research at the International Microwave Symposium 2025 in San Francisco, United States. Mr BI is the first undergraduate student from a Hong Kong higher education institution to receive this prestigious opportunity. As the first author of the groundbreaking research paper titled "Frequency-Query Enhanced Electromagnetic Surrogate Modeling with Edge Anti-aliasing Pixelation for Bandpass Filter Inverse Design," he has demonstrated PolyU's prominence in the field of microwave engineering. Mr BI’s research introduces an innovative frequency-domain attention modelling framework based on Transformer architecture. Addressing significant challenges in the intelligent design of microwave devices, this framework differs from traditional convolutional neural networks (CNNs) and fully connected networks (MLPs). Through frequency query mechanism and dynamic attention weight allocation, it enables the global correlation of electromagnetic response, and effectively resolves the parameter coupling issue in diagonal connection modelling of microstrip structures. Experimental results have shown that the new proxy model can accurately predict device performance with high precision using minimal data. This methodology has been successfully applied to designing ultra-compact bandpass filters, offering a new and interpretable design approach for complex microwave integrated circuits. PolyU's success in nurturing interdisciplinary talent is demonstrated by the achievements of its young researchers. This international accomplishment not only inspires more students to pursue advanced scientific and technological research but also showcases the cutting-edge innovation capabilities of Hong Kong's young researchers to the international academic community. The International Microwave Symposium is hosted by the Microwave Theory and Techniques Society (MTT-S) under the Institute of Electrical and Electronics Engineers (IEEE). It brings together the world's latest research in microwave, radio frequency, wireless technology and high-frequency semiconductor technology. Additionally, it promotes international technical exchanges and cooperation through conferences, seminars, group discussions and exhibitions.

Media interview: PolyU Research Symposium highlights the intersection of blockchain and AI in Web3

The Hong Kong Polytechnic University (PolyU) and its Research Centre for Blockchain Technology (RCBT) successfully hosted The Hong Kong Research Symposium at Consensus Hong Kong on 20 February. This landmark event provided a unique platform for leading experts, researchers, and industry pioneers to discuss advancements in blockchain, Web3, decentralised artificial intelligence (AI), and post-quantum cryptography — technologies that are redefining global technological and economic landscapes. This symposium was the only university-led session at Consensus Hong Kong, reinforcing PolyU’s pivotal role in driving the future of decentralised technologies. The keynote sessions featured esteemed speakers who shared insights on emerging technologies. Among them was Prof. Jiannong Cao, Dean of Graduate School, Otto Poon Charitable Foundation Professor in Data Science, and Chair Professor of Distributed and Mobile Computing at PolyU. In his speech, he discussed the utilisation of AI in decentralised environments and the role of blockchain in enhancing trust and coordination. Prof. Man Ho Allen Au, Professor and Associate Head (Research and Development) of the PolyU Department of Computing, and Prof. Daniel Xiapu Luo, Professor and Associate Dean (Research) of the Faculty of Computer and Mathematical Sciences and Director of RCBT at PolyU, moderated a panel discussion. They highlighted PolyU’s commitment to academic excellence and its endeavors to position Hong Kong as a premier Web3 hub while also introducing RCBT’s dedication to innovative research and the evolving realm of Web3. In addition, Prof. Au and Prof. Luo conducted a media interview to share PolyU’s dedication to advancing education and blockchain research, as well as their groundbreaking work on zero-knowledge proofs. They offered valuable insights into the future of decentralised applications and their implications on financial infrastructure. The symposium attracted a large number of participants, and the active cooperation and efficient knowledge sharing between academia and industry successfully demonstrated the significant role of collaborative innovation in driving technological advancements. RCBT will continue its commitment to leading-edge research in the blockchain field, promoting technological breakthroughs, and facilitating academic exchanges to advance industrial development.  

PolyU signs MoU with Peking University Health Science Center to foster medical technology research and development of interdisciplinary medical disciplines

The Hong Kong Polytechnic University (PolyU) and Peking University Health Science Center (PKUHSC) have signed a Memorandum of Understanding (MoU) to explore collaboration in the field of medical technology, including joint research projects and academic exchanges. Leveraging the research capability and academic resources of the PolyU Faculty of Health and Social Sciences and PKUHSC Institute of Medical Technology, this collaboration aspires to promote the development of interdisciplinary medical disciplines and advance medical technology. The MoU was signed by Prof. Wing-tak WONG, PolyU Deputy President and Provost, and Prof. WANG Jiadong, Vice President of PKUHSC. Mr Ben LAU, PolyU Associate Vice President (Campus Development and Facilities); Prof. David SHUM, Dean of the PolyU Faculty of Health and Social Sciences; Prof. Jing CAI, Head of the PolyU Department of Health Technology and Informatics; Prof. YIP Shea-ping, Chair Professor of Diagnostic Science and Molecular Genetics of the PolyU Department of Health Technology and Informatics; as well as Prof. LIU Hong, Director of the PKUHSC Education Department; Prof. WANG Qing; Vice Dean of the PKUHSC Graduate School; Ms LI Xiaojia, Deputy Director of the PKUHSC Department of Hong Kong, Macao and Taiwan Affairs; and Prof. HAN Hongbin, Dean of the PKUHSC Institute of Medical Technology, attended the signing ceremony. Prof. Wing-tak Wong said that PolyU was accelerating the development of interdisciplinary medicine and engineering, and this partnership would significantly benefit the two universities’ work in developing advantageous academic disciplines as well as their professional development. He anticipates further collaborative projects between PolyU and PKUHSC, particularly in teaching and research, to foster mutual learning, while also hopefully expanding the scope of their cooperation, including through seed funding for research, with the aim of making a meaningful contribution to the advancement of medical technology. Prof. Wang Jiadong applauded the previous preliminary collaboration between the two universities in developing medical technology-related disciplines and in enabling exchanges between faculty and students. He emphasised the importance for PKUHSC of joining forces with universities in Hong Kong and expressed his willingness to expand collaboration with PolyU through this MoU to enhance both universities’ development of advantageous disciplines and to forge partnership in research. After the signing ceremony, the PolyU delegation had in-depth discussions with PKUHSC scholars about potential collaboration opportunities in medical education, joint research and student training. Both parties introduced their respective universities’ education and research development, as well as their progress in developing advantageous disciplines. The PolyU delegation also visited PKUHSC Institute of Medical Technology Education Laboratory, Peking University Nursing Simulation Center and Peking University Third Hospital Clinical Training Center to learn more about PKUHSC’s advanced facilities for developing medical technology and its extensive experience in clinical education. With over 45 years of extensive experience in healthcare education, PolyU has trained over 52,000 graduates across various healthcare professions, playing a pivotal role in the development of Hong Kong’s medical system. The University offers programmes in physiotherapy, occupational therapy, radiotherapy, optometry, medical laboratory science, speech therapy and nursing. Supported by a robust team of over 1,300 healthcare-related teaching and research staff and equipped with more than 90 specialised laboratories and research facilities, PolyU has leveraged its advantage in medicine-engineering integration to advance healthcare technology. In addition to the collaboration with PKUHSC, PolyU has established partnerships with several universities and hospitals in mainland China, and is actively preparing for the establishment of the third medical school to meet the medical needs of Hong Kong and the Greater Bay Area.

PolyU researchers make breakthrough discovery in structure and synthesis of 2D ferroelectrics, advancing technological development in microelectronics, artificial intelligence and quantum information

With their spontaneous electrical polarisations switchable by an external electric field, ferroelectrics have wide-ranging applications in transistors, memory, neuromorphic devices and more. In particular, two-dimensional (2D) ferroelectrics produced at the nanometre scale have emerged as superior materials for ultra-thin devices. A research team led by Prof. Jiong ZHAO, Associate Professor of the Department of Applied Physics of The Hong Kong Polytechnic University (PolyU), has conducted research on the structure and potential of 2D van der Waals materials, and has unveiled a pioneering approach for large-scale synthesis of 2D ferroelectrics. Their findings significantly boost technological advancements in microelectronics, artificial intelligence and quantum information, and will subsequently foster the development of diverse applications including high-density memory devices, energy conversion systems, sensing technologies and catalysis technologies. Compared to conventional materials, 2D ferroelectrics exhibit rapid carrier mobility, enabling swift data transfer, storage and computation. The notably reduced size of these materials also leads to considerably lower energy consumption. Moreover, their extreme thinness makes them exceptionally transparent and flexible, rendering them ideal for devices requiring these properties. Among the discovered 2D ferroelectrics, Indium Selenide (In2Se3) stands out as the most promising due to the co-presence of paraelectric, ferroelectric and antiferroelectric phases within its 2D quintuple layers. However, large-scale synthesis of 2D In2Se3 films with the desired phase is still lacking, while the stability for each phase also remains unclear. To overcome the challenges, the research team utilised the transmission electron microscopy (TEM) technique to directly observe and analyse the ferroelectric domains, domain walls and other crucial features at the atomic level within the materials. They found that 2D In2Se3 films with pure phase can be synthesised separately by first controlling the Se/In ratios in the precursors when growing 2D In2Se3 films through chemical vapour deposition and then transferring the as-grown films onto flexible or uneven substrates. After repeated experiments, they successfully implemented phase-controllable synthesis and achieved precise structural control deemed unattainable previously. The findings have been published in the international journal Nature Nanotechnology. The research team has also sought to explore novel 2D van der Waals materials and their potential. Using TEM, they have revealed a general plastic deformation mode in metal monochalcogenides, such as InSe, which contributes to the ultra-high plasticity of materials made by 2D metal monochalcogenides. The findings exhibit great potential for producing a high-performance plastic inorganic semiconductor and facilitate development of soft and flexible electronic materials, advanced additive manufacturing for semiconductors as well as solid-state lubricants. The research has been published in the journal in Nature Materials. In a recent study, Dr Zhao’s team has additionally uncovered the in-plane polar vortex in 2D materials with twisted bilayers with the help of the advanced four-dimensional scanning transmission electron microscopy (4D-STEM). They also demonstrated the relation between the twist angle in the bilayers and their vortex patterns and polar structures, as well as the potential to manipulate the polar vortices and polar field distributions through an external electric field or interlayer and twisting. The discovery not only provides valuable perspectives on the complex behaviour of polar structures in twisted 2D bilayers but also paves the way for tuning emergent quantum properties at the atomic scale and creating promising 2D materials. The research has been published in Science. PolyU research facilities, specifically the recently inaugurated Atomic Transmission Electron Microscopy Laboratory (AEML) under the University Research Facility in Materials Characterisation and Device Fabrication (UMF), have been crucial in facilitating these research endeavours. The Laboratory enables atomic resolution observations, which helped the team to directly reveal the critical mechanisms essential for synthesis and applications. The research also greatly benefited from the contributions of the research team of Prof. Daniel LAU Shu Ping, Chair Professor of Nanomaterials and Head of the PolyU Department of Applied Physics; Prof. Ming YANG, Assistant Professor of the PolyU Department of Applied Physics; and Prof. LY Thuc Hue, Associate Professor of the Department of Chemistry of City University of Hong Kong. Prof. Jiong Zhao said, “These scientific discoveries are set to usher in a paradigm shift in microelectronics and integrated circuits, while also driving the development of flexible, durable and efficient new-generation electronic devices. They will further open up promising prospects for various applications, such as new computation-in-memory devices with enhanced computation capacity and speed, and with no need for the data transfer between computation and memory units required in current computing chips. These advancements herald a new technological era where society is faster-moving, and is more energy-efficient and adaptable to change. With his outstanding research achievements, Prof. Zhao has been awarded the Excellent Young Scientists Fund by the National Natural Science Foundation. His research projects have also received support from the Collaborative Research Fund of the Research Grants Council and the Innovation and Technology Fund of the Innovation and Technology Commission.

PolyU led discussion on AI’s transformative impact on education and research at the 2nd Asian Universities Science and Technology Innovation Forum

PolyU participated in the 2nd Asian Universities Science and Technology Innovation Forum, held in Tokyo on 17-18 February. The event was co-organized by the China Association for International Exchange of Personnel (CAIEP) and the Japan Science and Technology Agency (JST).  The forum aimed to promote collaboration and foster knowledge exchange among universities to address global challenges and drive sustainable development. As the main supporting university representative from Hong Kong, Prof. Christopher Chao, Vice-President (Research and Innovation) of PolyU, joined a roundtable discussion on the transformative impact of AI and digitalisation in education. In his speech, Prof. Chao emphasised the crucial role of artificial intelligence (AI) in the future of education, research, and technology transfer. He highlighted AI’s potential as a tool in educational settings, its ability to drive innovation and breakthroughs in fundamental research, and its capacity to reduce costs in technology transfer. On the second day of the event, Prof. Chao led a dialogue with university leaders to explore collaborative opportunities and foster partnerships aimed at creating sustainable solutions that benefit both academia and society. The event brought together over 30 university leaders from across Asia, including representatives from China (Hong Kong and Macau), Japan, and other Asian countries and regions. Notable participants included PolyU, Peking University, University of Science and Technology of China, Fudan University, National University of Singapore, Nanyang Technological University and Waseda University, among others.  PolyU is committed to advancing translational research, fostering technological innovation, and nurturing talent. By continuing to build strong collaborative relationships with global universities, PolyU aims to transform challenges into opportunities, drive innovation, and contribute to global sustainable development and societal progress.  

PolyU signs collaborative agreements with the China Mobile (Hong Kong) Innovation Research Institute to advance research in AI, 6G, and Web 3.0

The Hong Kong Polytechnic University (PolyU) and the China Mobile (Hong Kong) Innovation Research Institute have formed a partnership by signing a memorandum of understanding (MoU) and a collaborative agreement. This strategic collaboration aims to propel the development of cutting-edge technologies, including artificial intelligence (AI), 6G and Web3.0, reinforcing Hong Kong as an international hub for innovation and technology (I&T). Leveraging PolyU’s interdisciplinary research excellence and academic expertise, and the research and development resources and experimental environment provided by the China Mobile (Hong Kong) Innovation Research Institute, this partnership aims to integrate the unique advantages of both parties to propel fundamental research and technological innovation. In addition, a comprehensive talent exchange and training framework will be established, featuring a joint training programme for talents and internship opportunities for doctoral students. The aim is to nurture high-tech professionals who can meet the evolving demands of future technological advancements. The signing ceremony was held at PolyU on 19 February. Witnessed by Ms Lilian CHEONG, Under Secretary for Innovation, Technology and Industry of the HKSAR Government; Prof. Jin-Guang TENG, PolyU President; Mr LING Hao, Chairman of China Mobile Hong Kong Company Limited; Prof. Christopher CHAO, PolyU Vice President (Research and Innovation) and Dr LIN Erwei, Chief Executive Officer and Director of China Mobile International Limited, the MoU was signed by Prof. LI Qing, PolyU Chair Professor of Data Science and Head of the Department of Computing and Mr SHEN Weizhong, President of China Mobile (Hong Kong) Innovation Research Institute. Subsequently, a collaborative agreement was signed by Prof. CAO Jiannong, Dean of the PolyU Graduate School and Chair Professor of Distributed and Mobile Computing, and Mr SUN Lin, Vice-President of China Mobile (Hong Kong) Innovation Research Institute. Ms Lilian Cheong commended the collaboration between the two institutions which is set to drive significant advancements in research and industrial development across key areas such as AI, 6G, and Web3.0. By leveraging collaboration between industry, academia and research, this partnership will inject new momentum into Hong Kong’s I&T development, and strengthen the connection between local universities and enterprises, fostering technological innovation and industrial collaboration within the Guangdong-Hong Kong-Macao Greater Bay Area. Prof. Jin-Guang Teng stressed PolyU’s dedication to fostering technological innovation and nurturing skilled professionals in response to diverse global challenges. This partnership with the China Mobile (Hong Kong) Innovation Research Institute can more fully leverage the benefits of academia-industry synergy. Both parties will focus on the advancement and application of strategic technologies, including AI, 6G and Web3.0, as well as on cultivating a new generation of I&T talent, thereby providing strong support for Hong Kong’s social and economic development. Mr Shen Weizhong emphasised that the China Mobile (Hong Kong) Innovation Research Institute is committed to advancing cutting-edge technologies. This partnership will capitalise on the Institute’s expertise in technology application, industry influence and market reach to support PolyU’s translation of research outcomes, while also encouraging innovation and advancing the cultivation of high-end talent. Under the agreement, PolyU and the China Mobile (Hong Kong) Innovation Research Institute will collaborate closely in key areas of AI and Web3.0. In terms of AI, their focus will be on enhancing the development and deployment of large language models, improving task planning and problem-solving capacities, and driving the widespread adoption of AI across diverse industries. It aims to enhance Hong Kong’s competitive edge in the global AI landscape. In the realm of Web3.0, they will develop a robust and scalable distributed computing infrastructure to support large-scale model research and development, in alignment with Hong Kong government policies to harness blockchain technology. In addition, this partnership will drive innovation and transformation within the local financial industry, enhancing Hong Kong’s international competitiveness and solidifying its pioneering position in adoption of Web3.0 technologies. Further expanding the scope of their collaboration, the two parties, along with China Mobile Hong Kong, will also explore the potential of satellite-integrated precise positioning and low-altitude economic applications by utilising 5G networks to enhance high-precision positioning capabilities. This collaboration aims to support the development of Hong Kong’s smart city infrastructure and propel the growth of innovation across related industries. This partnership is of great significance, as it not only catalyses Hong Kong’s I&T development, but also promotes Hong Kong-Mainland integration, opening a new chapter of development for GBA in global technology industry.

PolyU and international scientists utilise satellite positioning data to unveil ice sheet melt behaviour in Greenland, aiding in the assessment of sea-level rise

Melting of the Greenland ice sheet is currently the primary driver of sea-level rise. For the first time, scientists from The Hong Kong Polytechnic University (PolyU), together with a team of global researchers, have integrated various modern space geodetic techniques, particularly satellite positioning data, to monitor the subsidence of vertical bedrock and successfully quantify summer water storage in the Greenland ice sheet. This achievement offers new insights and evidence regarding the contribution of ice sheets to global sea-level rise. Findings from their research have been published in the international journal Nature. The Greenland ice sheet is second in size only to Antarctica, with an ice thickness of about 3 kilometres. If it were to fully melt, the average global sea level would rise by seven metres. However, many questions remain unanswered regarding the processes of englacial water accumulation, storage, and ultimate release. Prof. Jianli CHEN, Professor of the PolyU Department of Land Surveying and Geo-informatics, and core member of Research Institute for Land and Space, collaborated with international experts from Hong Kong, Mainland China, the US, the Netherlands, and Belgium to explore the hydrological processes in Greenland. Their research focuses on the evolution of meltwater storage to better understand ice sheet melting behaviour and its impact on sea-level rise. The increase in water storage caused by the melting of ice sheets is one of the key factors leading to bedrock subsidence. However, the satellite gravimetry commonly used is not optimal for conducting regional assessment of Greenland hydrology. To tackle this challenge, the research team has pioneered the use of the Greenland GPS Network (GNET) and satellite gravity measurements provided by NASA’s Gravity Recovery and Climate Experiment. GNET comprises numerous Global Navigation Satellite System (GNSS) stations around Greenland to provide continuous positioning data. The team analysed data from 22 GNSS stations close to bedrocks and glacier outlets over the period from 2009 to 2015 to detect the regional melting water storage beneath the ice sheets and quantify the elastic deformation and subsidence of vertical bedrock, thereby better understanding the spatiotemporal behaviour of meltwater. GNSS was also used to help monitor large scale mass redistribution in the climate system, such as groundwater depletion and change in lake water storage. The study revealed that during the summer melt season, most of the meltwater is temporarily stored within the ice sheet, peaking in July and then gradually decreasing. The buffered meltwater leads to a maximum subsidence of up to 5mm in the bedrock near the GNSS stations in Greenland. In 2010 and 2012, extreme melting events led to the bedrock subsiding by as much as 12 and 14 millimeters, respectively. The study also suggested that the duration of meltwater storage in the ice sheet at most GNSS sites is about  8 weeks but with regional variation. It is above average at about 9 weeks in the northeast and west, while at around 4.5 weeks in the south and southeast. As recent extremely high summer temperatures may become the norm in the foreseeable future, accurate prediction of meltwater storage in those years is crucial for assessing sea-level rise. Since meltwater runoff modelled from regional climate models could have overestimated water retention or underestimated snowmelt runoff, the team suggested that upward adjustments of up to 20% may be necessary for the warmest years. Prof. Chen said, “This study, which involved years of preparation, not only integrated various modern space geodetic techniques but also involved challenging expeditions to some of the most remote areas of the planet. The significant results underscore the importance of extensive international cooperation in addressing climate change challenges. Our research will contribute to achieving accurate model performance for warmer years, aiding in the projection of ice-sheet behaviour and its impact on sea-level rise in the coming decades. This holds particular significance amidst anticipated Arctic warmings.”