John W. Pomeroy

John Pomeroy is a hydrologist based in Canada who studies glaciers, snow hydrology, and hydrological modelling. He has helped to develop hydrological technologies and methodologies used world-wide. In 2025, he was awarded the International Hydrology Prize - Dooge Medal by the International Association of Hydrological Sciences to recognize his contributions to climate science and the understanding of hydrological processes and predictions. He has also received the Miroslaw Romanowski Medal (GWFO), a world-wide university-led program for freshwater research and monitoring. He became the primary chairperson of the UNESCO Chair in Mountain Water Sustainability in 2023.

Pomeroy was the founding President of the International Commission for Snow and Ice Hydrology (ICSIH) serving from 2005-2013 and President of the Canadian Geophysical Union from 2007-2009. He has served as Chair of the International Decade for Predictions in Ungauged Basins. He is a Fellow of the Royal Geographical Society (2004),

Early life and education John Pomeroy grew up in Cleveland, Ohio near Lake Erie, which at the time was heavily polluted. After an initial year at the University of Indiana to study astrophysics, Pomeroy transferred to the University of Saskatchewan. He received his BSc from the Department of Geography in 1983, and his PhD in Agricultural Engineering from the College of Engineering in 1988. a Research Scientist with Environment Canada (1990-2000); and the first Professor of Hydrology in Wales, being appointed in 2001 to a personal chair at the University of Wales, Aberystwyth. He became a member of the Board of Directors of the Western Watersheds Climate Research Collaborative in Canmore, Alberta in 2008. In 2018, Pomeroy became Director of the Smart Water Systems Laboratory. a program for world-wide freshwater research and monitoring. He co-chaired the United Nations Advisory Board for the 2025 International Year of Glaciers' Preservation and Chair of the Ad Hoc Committee for the Decade of Action for Cryospheric Sciences (DACS).

Research Pomeroy has carried out research around the world, in countries including Canada, the United States, Bolivia, China, Chile, Japan, Nepal, Russia, Scotland and Wales. Pomeroy's Cold Regions Hydrological Model is a standard predictive model for Western Canada and other cold regions. Changes in glaciation are altering conditions in commonly used hiking and climbing areas, making travel in the mountains more dangerous.

The duration of snowcover in the Canadian Rockies has decreased by four to six weeks compared to the early 1970s. Alberta's glaciers and mountain snowmelt feed the South Saskatchewan River, determining water availability for the province and people of Saskatchewan. In addition to irrigation, decreasing water supplies will affect water availability to cities and generation of hydroelectric power. As a founding contributor, and later Chair of the IAHS Decade on Predictions in Ungauged Basins, Pomeroy developed the modular, physically based, multi-physics Cold Regions Hydrological Modelling Platform (CRHM) for diagnosing and predicting cold regions hydrology, used to evaluate new process representations and land use and climate change impacts on hydrology. HIs work leading the Global Water Futures program raised awareness of water research and its importance in understanding and adapting to climate change in both Canada and internationally. To determine future water supplies in cold regions, Pomeroy has used CHRM and MESH models to diagnose future climate change impacts on hydrology using combinations of statistically and dynamically downscaled climate models. These results show earlier freshets, reduced snowmelt peaks, increased evapotranspiration and rainfall-runoff and greatly decreased summer streamflow within the context of rising annual discharge volumes due to increased rainfall—climate change impacts in cold regions freshwater supply that contribute to the global water crisis. Pomeroy developed the theory of snow interception in forest canopies and its subsequent sublimation (Pomeroy and Schmidt, 1993; Pomeroy et al., 1998a; Hedstrom and Pomeroy, 1998) that is now used in forest hydrology and models around the world.

Awards and honors 2025, International Hydrology Prize - Dooge Medal, a joint award from the International Association of Hydrological Sciences (IAHS), United Nations Educational, Scientific and Cultural Organization (UNESCO), and World Meteorological Organization (WMO). 2021, Walter Langbein Lecture Award for hydrology, American Geophysical Union 2019, Miroslaw Romanowski Medal for environmental science, Royal Society of Canada 2017, J. Tuzo Wilson Medal for geophysics, Canadian Geophysical Union

Selected works Pomeroy has published at least a dozen books and more than 400 scholarly papers.