Relating storm-snow avalanche instabilities to data collected from the Differential Emissivity Imaging Disdrometer (DEID)

Journal Article · Thu Mar 30 00:00:00 EDT 2023 · Cold Regions Science and Technology

DOI:https://doi.org/10.1016/j.coldregions.2023.103839· OSTI ID:2420598

Morrison, Travis J. ^[1]; Meisenheimer, Trent ^[2]; Garrett, Timothy ^[2]; Singh, Dhiraj ^[2]; Donovan, Spencer ^[2]; Pardyjak, Eric ^[2]

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1. Particle Flux Analytics Inc., Park City, UT (United States); Univ. of Utah, Salt Lake City, UT (United States); OSTI
2. Univ. of Utah, Salt Lake City, UT (United States)

Storm-snow avalanches are challenging to forecast due to complex alpine terrain and during rapidly changing weather conditions. They can result in loss of lives and significant economic impact. We describe how a new device that continuously measures with high-frequency snowflake mass, size, density, and type, the Differential Emissivity Imaging Disdrometer (DEID), and show how the DEID can be used to aid avalanche forecasting when coupled with a storm-snow stability model. DEID measurements of snow accumulation, snow water equivalent (SWE), and snow density obtained during seventeen storms taken at the mid-Collins Snow-Study Plot at Alta Ski Area in Utah's Central Wasatch mountain range during winter 2020–2021 show excellent agreement with infrequent manual measurements. Additionally, two new variables, the Shape Density Index (SDI) and Complexity, are proposed and used to classify snowflake habit and estimate storm-snow shear strength. We illustrate how these DEID-derived data can be used to identify layers of concern in the storm snow such as density inversions, in real-time without digging snow pits. Furthermore, the DEID-data are used to run four variations of the SNOw Slope Stability model (SNOSS) for the storms investigated. The results are evaluated with data collected from tilt-board tests, infrasound measurements, and visual observations of avalanches. For a total fourteen storms analyzed, the DEID-driven SNOSS-modeled minimum stability index predicts the general stability of the storm-snow as indicated by observed avalanches, both natural and of unknown cause. Finally, the results provide a promising approach for nowcasting instabilities within storm-snow layers with a single instrument.

• Research Organization: Particle Flux Analytics Inc., Park City, UT (United States)
• Sponsoring Organization: USDOE Office of Science (SC)
• Grant/Contract Number: SC0017168
• OSTI ID: 2420598
• Journal Information: Cold Regions Science and Technology, Journal Name: Cold Regions Science and Technology Vol. 210; ISSN 0165-232X
• Publisher: Elsevier
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
DEID
Engineering
Geology
SNOSS model
Snow-density measurement
Storm-snow instability