This blog post is part of our series: “Highlights” for which we’re accepting contributions! Please contact one of the GM blog editors, Emily (eb2043@cam.ac.uk) or Emma (elodes@asu.edu), if you’d like to contribute on this topic or others.
Recently, EGU announced the 2025 medals and awards to be presented at the General Assembly in April, and the winner of the Geomorphology Division Ralph Alger Bagnold Medal is Professor Chris D. Clark, Sorby Chair of Geoscience, University of Sheffield. Professor Clark is a glacial geomorphologist working to understand the landforms that develop beneath glaciers and, after glaciers retreat, how such landforms may be used to reconstruct ice sheet behavior. Professor Clark has led major projects to understand past and future glacier behavior (BRITICE-CHRONO, PALGLAC), is a fellow of the Royal Geographical Society, and member of Academia Europaea and has taught and mentored numerous students, PhD’s and early career researchers as well as having served on editorial boards for Annals of Glaciology, Boreas, Earth Surface Processes and Landforms and the Journal of Maps. Our blog editors questioned Professor Clark to learn more about his background and success in geomorphology.
Chris D. Clark, in Greenland. (PC: Christiaan Diemont)
How would you explain or describe your research in brief?
My main curiosity is palaeo-glaciology; understanding the processes that produce glacial landforms, and using this along with their mapped distribution to reconstruct kilometers-thick ice sheets of the last glaciation. I have worked on bumps that spontaneously emerge as ice sheets flow over soft substrates. These include drumlins and subglacial ribs, and my favourite of all, Mega Scale Glacial Lineations (MSGL). These take me back to when I came across them in satellite images in Canada and named them during my Phd studies. In publications we argued that MSGL formed by fast flowing ice and are key for finding the main ice stream arteries within ice sheets.
My approach to reconstructing former ice sheets has been to try the whole ice sheet and work downwards, rather than bite off a smaller area and connect upwards. This isn’t easy. Mapping of landforms such as drumlins, moraines and meltwater traces across whole ice sheets have provided a framework on which to build palaeo-glaciological reconstructions. With numerous PhD students and postdocs, together we have spotted and hand-mapped millions of glacial landforms, captured in GIS and put alongside evidence from important field investigations from the published literature. The BRITICE Glacial Map is one example of this (Briticemap.org). Our landform-driven approach has led to reconstructions of the changing extent, flow dynamics, divide migrations and ice stream functioning of former ice sheets covering Canada, Greenland, Britain and Ireland, and Kamchatka, and soon I hope for the last Scandinavian Ice Sheet.
What questions are you interested in right now?
- To what extent does the retreat history (1000s of years) of the Greenland Ice Sheet matter for its future behavior in a warming world?
- Can glacial landforms recording ice flow direction be used to improve ice sheet model simulations of the last Scandinavian Ice Sheet?
What has been the biggest challenge of your career?
Leading the BRITICE-CHRONO project on reconstruction of the last British-Irish Ice Sheet. I led a dream team of 40 researchers over eight years, conducting 1500 person days of fieldwork across 914 sites, generating 639 new ages by radiocarbon, luminescence and cosmogenic methods. These ages constrain the timing of ice margin positions, and were integrated with landform maps to build a reconstruction that interacted with ice sheet modelling. I am still amazed at what we achieved, and in fact more than we set out to do in the proposal. What a team!
The BRITICE Glacial Map, which was sent to all school geogrpahy departments
What was a memorable experience or moment in your geomorphology career?
Having argued in 1993 from a palaeo-perspective that Mega Scale Glacial Lineations (MSGL) in Canada were the geomorphological record of ice streams. It was an absolute thrill when Julia Wellner and colleagues found them (2001) on the seafloor around Antarctica recording fast flow from modern ice streams.
Mega Scale Glacial Lineations (MSGL) from National Land Survey of Finland
What do you enjoy most about your job/work?
The day to day working with clever PhD students, postdocs and collaborators, puzzling over tricky shared endeavours.
What advice do you have to share with students and early career geomorphologists?
Follow what seems interesting to you, because a fruitful career in science needs to be fun and engaging on the way. Yes, take advice and nudges, but be wary of others telling you what is most important, or which method to use – fashions and trends come and go. Have confidence in your approach and take time to enjoy the discovery. Most of all, good luck!
