The Potential of Hydrogeodesy to Address Water‐Related and Sustainability Challenges
Authors: Jaramillo Fernando , Aminjafari Saeid , Castellazzi Pascal , Fleischmann Ayan , Fluet‐Chouinard Etienne , Hashemi Hossein , Hubinger Clara , Martens Hilary R. , Papa Fabrice , Schöne Tilo , Tarpanelli Angelica , Virkki Vili , Wang‐Erlandsson Lan , Abarca‐del‐Rio Rodrigo , Borsa Adrian , Destouni Georgia , Di Baldassarre Giuliano , Moore Michele‐Lee , Posada‐Marín José Andrés , Wdowinski Shimon , Werth Susanna , Allen George H. , Argus Donald , Elmi Omid , Fenoglio Luciana , Frappart Frédéric , Huggins Xander , Kalantari Zahra , Munier Simon , Palomino‐Ángel Sebastián , Robinson Abigail , Rubiano Kristian , Siles Gabriela , Simard Marc , Song Chunqiao , Spence Christopher , Tourian Mohammad J. , Wada Yoshihide , Wang Chao , Wang Jida , Yao Fangfang , Berghuijs Wouter R. , Cretaux Jean‐François , Famiglietti James , Fassoni‐Andrade Alice , Fayne Jessica V. , Girard Félix , Kummu Matti , Larson Kristine M. , Marañon Martin , Moreira Daniel M. , Nielsen Karina , Pavelsky Tamlin , Pena Francisco , Reager J. T. , Rulli Maria Cristina , Salazar Juan F. 
Published: November 2024

Increasing climatic and human pressures are changing the world's water resources and hydrological processes at unprecedented rates. Understanding these changes requires comprehensive monitoring of water resources. Hydrogeodesy, the science that measures the Earth's solid and aquatic surfaces, gravity field, and their changes over time, delivers a range of novel monitoring tools that are complementary to traditional hydrological methods. It encompasses geodetic technologies such as Altimetry, Interferometric Synthetic Aperture Radar (InSAR), Gravimetry, and Global Navigation Satellite Systems (GNSS). Beyond quantifying these changes, there is a need to understand how hydrogeodesy can contribute to more ambitious goals dealing with water‐related and sustainability sciences. Addressing this need, we combine a meta‐analysis of over 3,000 articles to chart the range, trends, and applications of satellite‐based hydrogeodesy with an expert elicitation that systematically assesses the potential of hydrogeodesy. We find a growing body of literature relating to the advancements in hydrogeodetic methods, their accuracy and precision, and their inclusion in hydrological modeling, with a considerably smaller portion related to understanding hydrological processes, water management, and sustainability sciences. The meta‐analysis also shows that while lakes, groundwater and glaciers are commonly monitored by these technologies, wetlands or permafrost could benefit from a wider range of applications. In turn, the expert elicitation envisages the potential of hydrogeodesy to help solve the 23 Unsolved Questions of the International Association of Hydrological Sciences and advance knowledge as guidance toward a safe operating space for humanity. It also highlights how this potential can be maximized by combining hydrogeodetic technologies simultaneously, exploiting artificial intelligence, and accurately integrating other Earth science disciplines. Finally, we call for a coordinated way forward to include hydrogeodesy in tertiary education and broaden its application to water‐related and sustainability sciences in order to exploit its full potential.