Snow cornice processes and hazard assessment possibilities

Holt Hancock1, Markus Eckerstorfer2, Jordy Hendrikx3

1Department of Arctic Geology, The University Centre in Svalbard2Earth observation department, NORCE3Snow and Avalanche Lab, Department of Earth Sciences, Montana State University

Cornices are overhanging masses of snow

Cornice systems in Longyearbyen are readily observable and endanger infrastructure

Traditional cornice process monitoringhas been achieved with mostly manual field observations.

(Vogel et al., 2012)

TLS (terrestrial laser scanning) can help refine ourprocess understanding of cornice growth and failure.

And we can display detailedcornice data in both 2D…

Platåberget Gruvefjellet

…and 3D

Change in snow

surface (m)

Cornices grow rapidly under specificmeteorological conditions.

We measured growthrates in excess of 40 cm / day.

Platåberget Gruvefjellet

Key takeaways: Accretion Matters!

Conditions conducive to cornice accretion (and failure) also promote sensitive wind slab development.

Key takeaways: Accretion Matters!

Conditions conducive to cornice accretion (and failure) also promote sensitive wind slab development.

Cryoslope Svalbard photo

Key takeaways: Travel Advice

Expect cornices to form with the first snowfalls.

Key takeaways: Travel Advice

Cornices can fail much further back than expected.

Key takeaways: Travel Advice

Cornices can fail much further back than expected.

Questions?

Further Reading:

• Eckerstorfer, M. and Christiansen, H.H., 2011c. Topographical and meteorological control on snow avalanching in the Longyearbyen area, central Svalbard 2006–2009. Geomorphology, 134(3): 186-196.

• Hancock, H., Prokop, A., Eckerstorfer, M., Hendrikx, J. and Borstad, C., 2018. Monitoring cornice dynamics and associated avalanche activity with a terrestrial laser scanner, International Snow Science Workshop, Innsbruck, Austria, pp. 323-327.

• Montagne, J., McPartland, J., Super, A. and Townes, H., 1968. The Nature and control of snow cornices on the Bridger Range, Southwestern Montana, Alta Avalanche Study Center, Miscellaneous Report.

• Vogel, S., Eckerstorfer, M. and Christiansen, H., 2012. Cornice dynamics and meteorological control at Gruvefjellet, Central Svalbard. The Cryosphere, 6(1): 157-171.