While glacier advance is extremely rare, study of advancing glaciers offers a more complete picture of glacier dynamics and the factors that enable such advances.  In Alaska, Yahtse Glacier is the fastest advancing glacier.  After a 40-km 20th century retreat, it has advanced 2.5 km since 1990, and is thickening by several meters per year over its terminus.  During this advance, the terminal stresses have transitioned from tensile to compressive, and the driving stresses have dropped by a factor of 3.  All of these changes at the Yahtse terminus have occurred despite net mass loss over the entire Yahtse Glacier basin, reflected by thinning in the upper reaches of the glacier.

We suggest that continued growth and progradation of a submarine morainal bank, and a steep icefall which dynamically isolates the terminus region from the upper basin, are critical for the sustained advance of Yahtse Glacier.

This work was led by Joey Durkin, a Ph.D. student at Cornell University, and published in Frontiers in Earth Science.

Three new papers are now in press in Geophysical Research Letters, Journal of Glaciology and the Annals of Glaciology.  These papers are:

Bartholomaus, T. C., L. A. Stearns, D. A. Sutherland, E. L. Shroyer, J. D. Nash, R. Walker, G. Catania, D. Felikson, D. Carroll, M. J. Fried, B. Noël, M. van den Broeke (in press), Contrasts in the response of adjacent fjords and glaciers to surface melt in western Greenland, Annals of Glaciology.

In which we integrate glaciological and oceanographic observations from the west coast of Greenland to demonstrate how subglacial hydrology has contrasting effects on the glacier and fjord dynamics within neighboring systems.

Gimbert, F., V. C. Tsai, J. M. Amundson, T. C. Bartholomaus, and J. I. Walter (in press), Sub-seasonal pressure, geometry and sediment transport changes observed in subglacial channels, Geophysical Research Letters.

In which we demonstrate how seismic and discharge measurements can be combined to identify how subglacial pressure gradients within Rothlisberger channels and channel size vary over the course of the melt season at a glacier in Alaska.  Additionally, we discuss variations in sediment transport and the impact of flowing water on glacier motion.

Brinkerhoff, D., C. R. Meyer, E. Bueler, M. Truffer, and T. C. Bartholomaus (in press), Inversion of a glacier hydrology model, Annals of Glaciology, 57(72).

In which we constrain the evolution of the subglacial hydrologic system through measurements of glacier water discharge, glacier motion, and estimates of water inputs.