Colin Gleason is an outstanding hydrologist and one of the world’s leading researchers working today in the field of remote sensing for fluvial geomorphology. He is responsible for multiple groundbreaking findings at the interface of hydrology and geomorphology across many scales.

Despite only completing his Ph.D. in 2016, Dr. Gleason’s work has already contributed exciting new lines of research and deepened our understanding of a number of long-standing debates in fluvial geomorphology, in particular through his discovery of “at-many-stations hydraulic geometry,” or AMHG. Classical hydraulic geometry theory was originally formulated in the 1950s and was studied extensively in the 1960s, 1970s, and 1980s. Received wisdom was that there was little left to learn, yet as a Ph.D. student Dr. Gleason spotted a connection that had been missed. Specifically, what Colin uncovered was that the coefficients in hydraulic geometry theory were closely correlated in a log linear manner. In further work, Dr. Gleason has provided a theoretical explanation for the empirical AMHG result and shown that it is fully consistent with previous work. Not only is AMHG a major scientific breakthrough, it has also proved exceptionally powerful and has led to (1) new methods to estimate river discharge from space that are currently being implemented operationally in the forthcoming Surface Water and Ocean Topography (SWOT) satellite mission; (2) new insights into arctic hydrology; and (3) a fundamental reconsideration of the broad canon of hydraulic geometry theory.

Moreover, Dr. Gleason contributes substantially to his discipline through various important roles within the Mission Science Team for the recently launched NASA/CNES SWOT satellite where he coleads the Discharge Algorithm Working Group. This team is responsible for producing the operational architecture to estimate discharge along all global rivers greater than 50 meters wide (i.e., at millions of sites globally). This architecture needs to run in near-real time and ingest many terabytes of data every day to produce outputs that will be used (and critically evaluated) by many tens of thousands of scientists globally. Colin’s leadership has thus resulted in a critical component and backbone of the SWOT mission data system, and in guiding the development of this over the past decade, Colin has performed an immeasurable service for this community.

—Paul Bates, University of Bristol, Bristol, U.K.

This award means quite a lot to me, and even more so after reading Paul Bates’s citation written with Larry Smith, Tamlin Pavelsky, and Dennis Lettenmaier. I admire these hydrologists, and it’s humbling to read their citation. I am grateful to Kostas Andreadis for suggesting this honor to that group. I want to say thank you to each of these folks, and to my other mentors in science, Mike Durand, Casey Brown, and Don DeGroot, for believing in me and nurturing my interest in doing perhaps slightly sideways hydrology. I thank my department for breaking precedent and hiring its first nonengineering Ph.D. and for trusting me to start as faculty 6 months after my Ph.D. finished. I thank NASA’s acronym-loving SWOT, HMA, THP, WR, NIP, and AIST programs for their support alongside the National Science Foundation’s Arctic Natural Sciences (ANS) program. Finally, I thank my undergraduate program in Forest Engineering (now ERE) at State University of New York College of Environmental Science and Forestry (SUNY-ESF) for setting my life on a very different path. They insisted I was capable of and suited for a career in research, and with no known examples to follow I would not be writing this response without their strong push. It is disingenuous to keep saying “I” in this response. It is my students, staff, postdocs, colleagues, and collaborators who enable everything we do, and this award is extra meaningful to us given how we see the hydrologic world. We are an odd mix of fieldwork, fluvial geomorphology, remote sensing methods, applied geochemistry, software engineering, machine learning, and global-scale data science focused exclusively on the satellite era. We believe that global rivers are, well, rivers. To us, this means vector entities flowing daily across complete network topologies that honor individual river hydrologic, human, and landscape histories for every river on the planet. En route to this goal, we’ve fashioned a global hydrology lens with strict definitions of “ungauged basins,” insistence on detail at-scale, centering of primary data (in situ and orbital), methodological agnosticism, and a focus on the hydrology of “what is.” This approach, together with our acceptance of low skill, confuses reviewers who wonder why we didn’t just calibrate a model. I have therefore frequently wondered whether we’re headed in the right direction, but this honor validates our north star as true. It means a lot to us, and I hope to others like us. Finally, to Binglei: Rising to match your example every day is the greatest privilege of my life. —Colin J. Gleason, Civil and Environmental Engineering, University of Massachusetts Amherst