Glaciers and ice sheets play key roles in the long story of Earth’s climate and landscapes.
Today, changes in the cryosphere also impact society on local and global scales. These changes ultimately depend on how climate variations are filtered through ice dynamics. Research in the UO Glacier and Climate Dynamics group focuses on these interactions, using computational models, theoretical models, and data analysis to investigate how glaciers and ice sheets respond to climate forcing and other environmental changes. We enjoy working on these problems with collaborators near and far.
Check out some specific research areas below:
Marine ice-sheet variability
The massive glaciers draining the Greenland and Antarctic Ice sheets are sensitive to atmospheric and oceanic changes, and many have retreated rapidly in recent decades. But they exist in settings with vigorous natural variability. Furthermore, ice-dynamic changes are mediated by their underlying bedrock topography, which can mean the difference between abrupt retreat or more stable margins. We are using ice-flow models to explore such questions as:
How does uncertain bed topography affect simulations of past terminus fluctuations? (led by postdoc Schmitty Thompson)
How did Greenland’s glaciers respond to rapid warming in the Early 20th century, and what are the implications for simulations of more recent behavior?
How does the response to long-term trends “emerge” from natural variability in these sensitive systems?
Our work in this area is currently supported by a grant from NSF Arctic Natural Sciences.
Ice-flow and Sediment interactions
Glaciers and ice streams deposit sediment at their margins. In marine settings, this can have important feedbacks on ice dynamics by building topography and providing drag in the grounding zone, where ice goes afloat. We are using ice-flow models that include sediment deposition to explore these processes, with the goal to shed light on sediment deposits left by glaciers and ice streams in the past, and to understand feedbacks that affect ice-sheet stability. For example:
Can sedimentation pause or reverse the retreat of marine ice sheets? (See recent paper)
When do submarine moraines reflect climate vs. sediment controls? (Led by graduate student Alma Diaz)
Mountain glaciers
Mountain glaciers are simpler than their tidewater cousins, but there are thousands of them worldwide, spanning a huge range of geometries and climate settings. It’s important to understand how the fundamental ice dynamics translate from one setting to another. For example, glaciers have a response time that depends on their geometry and local climate, meaning that they are in varying stages of adjustment to current warming.
Research interests in this area include:
Controls on the timing of “peak water” from glacier melt
Assessing how much glacier loss is attributable to human activity vs. natural variability
Assessing the past extent and current melt rates of glaciers in the Pacific Northwest
Climate variability and glacier mass balance
Glaciers depend on a balance between precipitation and melt. Natural climate variability makes this balance noisy on short timescales, creating statistical challenges both for observations and models. We’re interested in this upstream climate variability that affects glaciers and ice sheets, and how to characterize it in space and time.
Past projects assessed atmospheric variability that affects mountain glaciers (paper), and more recently on the atmosphere-ocean variability relevant to Greenland’s outlet glaciers.