1128

Approaching Middle Teton Glacier in the north fork of Garnet Canyon.

During May 30 and June 1, 2019 Inversion Labs completed field work as part of a mass balance survey of the Middle Teton Glacier in Grand Teton National Park (GTNP). We are excited to be collaborating with GTNP on this project as part of ongoing glacial monitoring efforts. The study of Middle Teton Glacier is managed by Reba McCracken (physical science technician) and Simeon Caskey (physical science branch chief). Huge thanks to both Reba and Simeon for the time and effort they contributed to make this project happen! Visit these links to learn more about glaciers and glacial features and glacier monitoring in GTNP.

This survey aims to enhance the park’s understanding of changes in the extent of Middle Teton Glacier by measuring patterns in accumulation and melt (ablation) on the glacier surface. Ablation stakes are installed on the glacier surface at the end of the accumulation season (late April to mid May) and persist in the ice through the end of the melt season (late September). Over the course of the melt season, snow and ice melt is monitored by measuring changes in the glacier surface at these stakes. When the stakes are installed in the spring, just before the melt season begins, the depth of the snow on the glacier surface represents the mass added to the glacier over the course of the accumulation season, its winter balance. As they melt out over the summer, the amount of snow and ice lost represents the glacier’s summer balance. Measurements taken at these stakes can be used to understand the glacier’s overall annual mass balance. They can be projected to account for changes across the entire glacier surface. Thus, this survey will establish a network of ablation stakes on Middle Teton Glacier that will be installed and measured each year into the future. Additionally, measurements of the snowpack depth across the glacier surface and of snow density will give insight into mass accumulation patterns (and potentially processes) on Middle Teton Glacier.

Field work completed in the 2019 spring accumulation survey included:

  • 48 snow depth measurements, with depths ranging 285 cm to >850 cm
  • Installation of three ablation stakes in holes drilled to 12-13 meters depth
  • Snow density profile in a 4.5-meter snow pit

Click here to see a preliminary map of snow depth results (drafted by GTNP).

1129

Ascending the glacier. Wet slide debris is estimated to significantly contribute to snow depth across the glacier.



1137

Completing traverses across the glacier to measure snow depths with an 8.5 meter probe.



1140

The Heucke steam drill. This lightweight steam-driven ice drill was used to drill ~13 meter holes for installation of ablation stakes. An installed stake is visible behind the drill.



1154

Assembling and labeling PVC sections for ablation stake installation.



1239

Snow density sampling using a SnowMetrics 250 cc density cutter and digital scale.



1238

Probing for the ice surface at the bottom of the 4.5-meter snow pit.