Assessing the Vulnerability of Alaska’s Glaciers in a Changing Climate

Retreating glaciers are an iconic image of climate change;yet not all glaciers in Alaska are actively retreating, and a few glaciers are even advancing. While this contrasting behavior can be misleading for the casual observer, variable responses between glaciers in a changing climate are expected. Glaciers act as conveyor belts that transport snow and ice from high elevations, where it does not melt, down to low elevations, where it does melt. A change in climate can impact the amount of snow and ice that accumulates (accumulation), the way snow and ice melt (ablation), or the conveyor belt (ice dynamics). While these impacts vary with elevation and glacier shape, glacier changes have major implications for downstream communities, including changes in the amount and timing of streamflow, and a potential increase in hazards related to landslide activity and glacial lake outburst floods.  

The goal of this project is to organize newly available data, collected by satellites and aircraft, that encompass Alaska and Northwest Canada, and then use that data to understand which glaciers in the region are most vulnerable to changes in climate. To accomplish this, scientists examine a variety of characteristics, including the surface area of glaciers at higher elevations versus lower elevations, the elevation of snowline at the end of summer, and geometric characteristics like glacier slope, width, and thickness. Together, these variables allow scientists to generate several new datasets and to evaluate these along with existing data to create simple metrics to predict which glaciers are most likely to retreat dramatically, which glaciers should be relatively stable, and which glaciers might advance. The results will be presented in easy-to-understand, publicly available metrics of glacier vulnerability. This information can be used by federal, state, local, or private entities planning land management, infrastructure, and recreation projects.