The 2022 Ralph Alger Bagnold Medal is awarded to Paola Passalacqua for innovative and impactful research on landscape dynamics through a rigorous mathematical approach, including using network theory to study delta systems, alongside outstanding community service.
Paola Passalacqua has rapidly established herself as a world leader in mathematical geomorphology through her innovative and impactful research on understanding landscapes and their dynamics from analysis of high-resolution topography. Passalacqua’s research has introduced a rigorous mathematical framework for the accurate and robust extraction of geomorphic features from high-resolution topography, leveraging innovative high-level mathematical methods from diverse fields. Passalacqua has been exemplary in documenting her methods and making them freely available for others to use; packaging this framework resulted in a widely used open software that is contributing to advancing the science of landscapes as complex eco-geomorphic systems. Her review papers on analysing high-resolution topography are a testament of her vision and leadership in formulating critical questions for the geomorphologic community.
A specific geomorphic system in which Passalacqua’s scholarly and original work has provided powerful quantitative insight is that of distributary channels and river deltas. Passalacqua has led the way in the application of network and graph theory to deltaic distributary-channel networks, which prove to be much more complex than previously described. Passalacqua has championed the paradigm of a delta “connectome”: an interconnected system analogous to neurons in the brain. Her network-analysis approach has significantly increased our understanding of how the complex channels of deltaic systems self-organize to orchestrate the delivery of sediment, nutrients and water to the delta top and the shoreline. Understanding these distributary networks is vital to protecting heavily populated, ecologically important coastal systems threatened by rising sea levels and sediment starvation.
Passalacqua also stands out in her service to the scientific community. She has served in editorial roles for several journals, including Earth Surface Dynamics and Hydrology and Earth System Sciences, and actively serves several learned societies. Her home institute, the University of Texas, has repeatedly saluted the quality of her teaching and advising. Her scientific contributions have been recognised by several prestigious awards and fellowships in Italy and the USA. In her multiple roles as teacher, advisor, research scientist, and member of the scholarly and broader communities, she provides a powerful role model for younger scientists. Paola Passalacqua is, therefore, a very worthy recipient of the Bagnold Medal.