Wet slab release occurs due to what mechanism?

• A. Release of wind slab
• B. Release of slab caused by meltwater going between slab and weak layer
• C. New snow sliding on existing snow surface
• D. Release of dry, unconsolidated snow

Answer: (B)

Wet slab release happens when meltwater penetrates the interface between a cohesive snow slab and a weak layer beneath it. The meltwater lubricates that contact and raises pore water pressure, which weakens the strength of the weak layer while adding weight to the slab. This combination makes it easier for the slab to fail and slide on the damp, weakened layer, often allowing the failure to propagate and trigger a slab avalanche. This commonly occurs during warming periods or after melt events when the snowpack becomes wet.

Other scenarios describe different mechanisms: wind slabs form from wind-deposited snow and are typically a dry-slab process; new snow sliding on the surface is a separate condition not driven by meltwater at the slab-weak-layer interface; and dry, unconsolidated snow releases involve a dry avalanche mechanism without the lubricating effects of meltwater.