The Role of Surveying on the Juneau Icefield
Understanding the complex dynamics of a glacial system requires fundamental information such as the mass balance, depth and temperature of the ice, meteorological conditions, surface velocity vectors, strain rates, surface gradients, and changes in the surface elevation. Integrating all these elements allows us to evaluate the glaciodynamic response of the Juneau Icefield with respect to climatic conditions, and to possibly predict its future behavior.

The purpose of the survey program is to measure, evaluate, and monitor, on an annual basis, the surface velocity, strain rates, and changes in the surface elevation of the Juneau Icefield. Surface gradients along the longitudinal axis of the glaciers are measured, and daily ablation rates are determined. The data obtained from these measurements serve as the foundation for determining the mode of flow and the strain regime throughout the system. This, in conjunction with annual measurements of the surface elevation, allow us to answer questions such as "Are the glaciers getting thicker or thinner? What is the spatial distribution pattern of accumulation and ablation? Are the glaciers speeding up or slowing down? Is the glacier system undergoing a transition from one mode of flow to another? If so, could this lead to advancement or recession of the glaciers draining the Juneau Icefield?" Ultimately, the answers to these questions may have an impact on the social, political, and cultural dynamics of the area surrounding the Juneau Icefield.


Students survey a point on the Taku Glacier


Where Do We Survey?
The main focus of the survey program is on the Taku Glacier system. This includes the main trunk of the Taku Glacier and its numerous tributaries - the Demorest, Hades Highway, Southwest Branch, Northwest Branch, and Matthes Glaciers. Other GPS surveys are conducted on the Lemon, Ptarmigan, Gilkey, Llewellyn, and Cathedral Glaciers. Here's an interactive map of the Juneau Icefield showing the various glacier and mountain names. This interactive map shows the locations of all the GPS survey profiles.

Surveying on Hades Highway, with Michael's Sword in the background