The paper is very well written and the authors do a great job investigating and describing the details of what happened.

I have a couple of comments that I think should be mentioned in the paper. The wind. You related the wind to mechanical components like tree throw, but I don't think you mention the wind as an effect on the snow melt. See our DOGAMI SP-55 where we discuss the role of winds in snow melting. The combination of high wind and air temperature increase at the same time can significantly contribute to snow melting and melting rate. The wind blows the warm air into the snow which contributes to the snow melt. We talked with Ben Hatchett about this. If you look at your graph, the wind and air temperature seem to correlate both high in the time right before the landslide initiates. It is always very hard to say what exactly happened, but I think this is worth mentioning. Is there any way to know how much snow was on the ground days before the event? Even if it was neighbors or roads crews guess. This can clearly affect the terrestrial water input (TWI) above the initiation area, but also how much snow was on the benches? The snow on the benches could play a role in the saturation of the colluvium on the benches. Was there snow on the benches which also underwent rapid melt? I bring this up, because of the lack of likelihood of water from the top of the mountain flowing down the anti-dipping beds and benches and thus not a likely source of saturation of the bench colluvium, which leaves rain from antecedent moisture, rain from this event, and snowmelt all three needing to be directly onto the benches.

Again, really nice paper, authors! This will help Alaskans understand and reduce risk to debris flows.

Bill Burns

Oregon Department of Geology and Mineral Industries