The 2023 Julia and Johannes Weertman Medal is awarded to Etienne Berthier for outstanding scientific achievements in regional and global glacier mass change and remote sensing, and for immense service to the global cryospheric community.
Etienne Berthier has made outstanding scientific achievements in glaciology and remote sensing. His innovative work has allowed the estimation of glacier mass changes at regional to global scales, and strongly improved our understanding of cryospheric response to climate change and their contribution to sea level rise. He has contributed to worldwide community efforts to provide a global inventory of glaciers and their change over time, contributing to studies in the Alps, Andes, Alaska, and Iceland. He has revolutionised recent studies of the recent mass loss over timescales of decades in Alaska, High Mountain Asia and Patagonia, providing much more detail than was previously possible. His work is highly regarded and used by researchers worldwide. He was a 2021 Clarivate Highly Cited Researcher in the field of geosciences.
Berthier has pioneered the field of glacier change observations from satellite remote-sensing since the beginning of his career. His early studies were among the first remote sensing observations of glacier volume and ice flow changes for the comparatively small mountain glaciers. He applied his methods to observe regional glacier changes, in southern Alaska and the Pamir-Karakoram-Himalaya, providing the first detailed estimate of these regions to sea level rise. He contributed to community efforts to provide a global catalogue of glaciers and global glacier changes. His has contributed to many regional and local mass balance studies via field campaigns, so ensuring that he retains a knowledge of glaciers melting on the ground, rather than from space via satellite images alone.
Berthier’s scientific achievements are the result of his very deep knowledge of glacier mass loss and his evident commitment in the crysopheric research community. He has been scientific editor for more than 100 articles and reviewed more than 200 articles. His scientific rigor was acknowledged by a “Top Reviewer” and “Outstanding referee” awards. He is heavily involved in the community efforts to make glacier inventory data and satellite data in general more easily accessible for research. Etienne is a core team member of the “Global Land Ice Measurement from Space (GLIMS)” initiative, a part of the Global Terrestrial Network for Glaciers (GTN-G) of which the International Association of Cryospheric Sciences (IACS) leads the Advisory Board. His international contributions are also shown in the two projects, the Swiss Programme for International Research by Scientific Investigation Teams (SPIRIT) and Pleiades Glacier Observatory, which have helped establish connections between data providers (CNES, Airbus) and researchers. Finally, he put his skills in space photogrammetry at the service of other communities, enabling major advances in snow and landslide remote sensing.
Berthier has been inspirational to early career scientists, who has benefited greatly from his mentorship, support and encouragement. He is, not only a model scientist with an impactful publication record, a record of training future leaders in glaciology, an editor, an award winning referee, a community organizer and advocate, but also a kind and gentle person. His contributions are many, but equally notable are his many indirect contributions, supporting others without need of recognition. Berthier embodies the principles of open science and open collaboration. He helps others generously to do their best science. These attributes mark him as a Julia and Johannes Weertman Medalist.